/* Target-dependent code for the MIPS architecture, for GDB, the GNU Debugger.
- Copyright 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995
+ Copyright 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996
Free Software Foundation, Inc.
Contributed by Alessandro Forin(af@cs.cmu.edu) at CMU
and by Per Bothner(bothner@cs.wisc.edu) at U.Wisconsin.
/* FIXME: Put this declaration in frame.h. */
extern struct obstack frame_cache_obstack;
-/* FIXME! this code assumes 4-byte instructions. */
-#define MIPS_INSTLEN 4 /* Length of an instruction */
-#define MIPS_NUMREGS 32 /* Number of integer or float registers */
-typedef unsigned long t_inst; /* Integer big enough to hold an instruction */
-
#if 0
static int mips_in_lenient_prologue PARAMS ((CORE_ADDR, CORE_ADDR));
#endif
{ NULL, NULL }
};
+/* Table to translate MIPS16 register field to actual register number. */
+static int mips16_to_32_reg[8] = { 16, 17, 2, 3, 4, 5, 6, 7 };
+
/* Heuristic_proc_start may hunt through the text section for a long
time across a 2400 baud serial line. Allows the user to limit this
search. */
#define PROC_HIGH_ADDR(proc) ((proc)->high_addr) /* upper address bound */
#define PROC_FRAME_OFFSET(proc) ((proc)->pdr.frameoffset)
#define PROC_FRAME_REG(proc) ((proc)->pdr.framereg)
+#define PROC_FRAME_ADJUST(proc) ((proc)->frame_adjust)
#define PROC_REG_MASK(proc) ((proc)->pdr.regmask)
#define PROC_FREG_MASK(proc) ((proc)->pdr.fregmask)
#define PROC_REG_OFFSET(proc) ((proc)->pdr.regoffset)
} *linked_proc_desc_table = NULL;
+/* Tell if the program counter value in MEMADDR is in a MIPS16 function. */
+
+static int
+pc_is_mips16 (bfd_vma memaddr)
+{
+ struct minimal_symbol *sym;
+
+ /* If bit 0 of the address is set, assume this is a MIPS16 address. */
+ if (IS_MIPS16_ADDR (memaddr))
+ return 1;
+
+ /* A flag indicating that this is a MIPS16 function is stored by elfread.c in
+ the high bit of the info field. Use this to decide if the function is
+ MIPS16 or normal MIPS. */
+ sym = lookup_minimal_symbol_by_pc (memaddr);
+ if (sym)
+ return MSYMBOL_IS_SPECIAL (sym);
+ else
+ return 0;
+}
+
+
/* This returns the PC of the first inst after the prologue. If we can't
find the prologue, then return 0. */
return 0;
}
+/* Decode a MIPS32 instruction that saves a register in the stack, and
+ set the appropriate bit in the general register mask or float register mask
+ to indicate which register is saved. This is a helper function
+ for mips_find_saved_regs. */
+
+static void
+mips32_decode_reg_save (inst, gen_mask, float_mask)
+ t_inst inst;
+ unsigned long *gen_mask;
+ unsigned long *float_mask;
+{
+ int reg;
+
+ if ((inst & 0xffe00000) == 0xafa00000 /* sw reg,n($sp) */
+ || (inst & 0xffe00000) == 0xafc00000 /* sw reg,n($r30) */
+ || (inst & 0xffe00000) == 0xffa00000) /* sd reg,n($sp) */
+ {
+ /* It might be possible to use the instruction to
+ find the offset, rather than the code below which
+ is based on things being in a certain order in the
+ frame, but figuring out what the instruction's offset
+ is relative to might be a little tricky. */
+ reg = (inst & 0x001f0000) >> 16;
+ *gen_mask |= (1 << reg);
+ }
+ else if ((inst & 0xffe00000) == 0xe7a00000 /* swc1 freg,n($sp) */
+ || (inst & 0xffe00000) == 0xe7c00000 /* swc1 freg,n($r30) */
+ || (inst & 0xffe00000) == 0xf7a00000)/* sdc1 freg,n($sp) */
+
+ {
+ reg = ((inst & 0x001f0000) >> 16);
+ *float_mask |= (1 << reg);
+ }
+}
+
+/* Decode a MIPS16 instruction that saves a register in the stack, and
+ set the appropriate bit in the general register or float register mask
+ to indicate which register is saved. This is a helper function
+ for mips_find_saved_regs. */
+
+static void
+mips16_decode_reg_save (inst, gen_mask)
+ t_inst inst;
+ unsigned long *gen_mask;
+{
+ if ((inst & 0xf800) == 0xd000) /* sw reg,n($sp) */
+ {
+ int reg = mips16_to_32_reg[(inst & 0x700) >> 8];
+ *gen_mask |= (1 << reg);
+ }
+ else if ((inst & 0xff00) == 0xf900) /* sd reg,n($sp) */
+ {
+ int reg = mips16_to_32_reg[(inst & 0xe0) >> 5];
+ *gen_mask |= (1 << reg);
+ }
+ else if ((inst & 0xff00) == 0x6200 /* sw $ra,n($sp) */
+ || (inst & 0xff00) == 0xfa00) /* sd $ra,n($sp) */
+ *gen_mask |= (1 << RA_REGNUM);
+}
+
+
+/* Fetch and return instruction from the specified location. If the PC
+ is odd, assume it's a MIPS16 instruction; otherwise MIPS32. */
+
+static t_inst
+mips_fetch_instruction (addr)
+ CORE_ADDR addr;
+{
+ char buf[MIPS_INSTLEN];
+ int instlen;
+ int status;
+
+ if (pc_is_mips16 (addr))
+ {
+ instlen = MIPS16_INSTLEN;
+ addr = UNMAKE_MIPS16_ADDR (addr);
+ }
+ else
+ instlen = MIPS_INSTLEN;
+ status = read_memory_nobpt (addr, buf, instlen);
+ if (status)
+ memory_error (status, addr);
+ return extract_unsigned_integer (buf, instlen);
+}
+
+
/* Guaranteed to set fci->saved_regs to some values (it never leaves it
NULL). */
/* What registers have been saved? Bitmasks. */
unsigned long gen_mask, float_mask;
mips_extra_func_info_t proc_desc;
+ t_inst inst;
fci->saved_regs = (struct frame_saved_regs *)
obstack_alloc (&frame_cache_obstack, sizeof(struct frame_saved_regs));
gen_mask = kernel_trap ? 0xFFFFFFFF : PROC_REG_MASK(proc_desc);
float_mask = kernel_trap ? 0xFFFFFFFF : PROC_FREG_MASK(proc_desc);
- if (/* In any frame other than the innermost, we assume that all
- registers have been saved. This assumes that all register
- saves in a function happen before the first function
- call. */
- fci->next == NULL
+ if (/* In any frame other than the innermost or a frame interrupted by
+ a signal, we assume that all registers have been saved.
+ This assumes that all register saves in a function happen before
+ the first function call. */
+ (fci->next == NULL || fci->next->signal_handler_caller)
/* In a dummy frame we know exactly where things are saved. */
&& !PROC_DESC_IS_DUMMY (proc_desc)
claims are saved have been saved yet. */
CORE_ADDR addr;
- int status;
- char buf[MIPS_INSTLEN];
- t_inst inst;
/* Bitmasks; set if we have found a save for the register. */
unsigned long gen_save_found = 0;
unsigned long float_save_found = 0;
+ int instlen;
- for (addr = PROC_LOW_ADDR (proc_desc);
- addr < fci->pc /*&& (gen_mask != gen_save_found
- || float_mask != float_save_found)*/;
- addr += MIPS_INSTLEN)
- {
- status = read_memory_nobpt (addr, buf, MIPS_INSTLEN);
- if (status)
- memory_error (status, addr);
- inst = extract_unsigned_integer (buf, MIPS_INSTLEN);
- if (/* sw reg,n($sp) */
- (inst & 0xffe00000) == 0xafa00000
-
- /* sw reg,n($r30) */
- || (inst & 0xffe00000) == 0xafc00000
-
- /* sd reg,n($sp) */
- || (inst & 0xffe00000) == 0xffa00000)
- {
- /* It might be possible to use the instruction to
- find the offset, rather than the code below which
- is based on things being in a certain order in the
- frame, but figuring out what the instruction's offset
- is relative to might be a little tricky. */
- int reg = (inst & 0x001f0000) >> 16;
- gen_save_found |= (1 << reg);
- }
- else if (/* swc1 freg,n($sp) */
- (inst & 0xffe00000) == 0xe7a00000
+ /* If the address is odd, assume this is MIPS16 code. */
+ addr = PROC_LOW_ADDR (proc_desc);
+ instlen = pc_is_mips16 (addr) ? MIPS16_INSTLEN : MIPS_INSTLEN;
- /* swc1 freg,n($r30) */
- || (inst & 0xffe00000) == 0xe7c00000
-
- /* sdc1 freg,n($sp) */
- || (inst & 0xffe00000) == 0xf7a00000)
-
- {
- int reg = ((inst & 0x001f0000) >> 16);
- float_save_found |= (1 << reg);
- }
+ /* Scan through this function's instructions preceding the current
+ PC, and look for those that save registers. */
+ while (addr < fci->pc)
+ {
+ inst = mips_fetch_instruction (addr);
+ if (pc_is_mips16 (addr))
+ mips16_decode_reg_save (inst, &gen_save_found);
+ else
+ mips32_decode_reg_save (inst, &gen_save_found, &float_save_found);
+ addr += instlen;
}
gen_mask = gen_save_found;
float_mask = float_save_found;
fci->saved_regs->regs[ireg] = reg_position;
reg_position -= MIPS_REGSIZE;
}
+
+ /* The MIPS16 entry instruction saves $s0 and $s1 in the reverse order
+ of that normally used by gcc. Therefore, we have to fetch the first
+ instruction of the function, and if it's an entry instruction that
+ saves $s0 or $s1, correct their saved addresses. */
+ if (pc_is_mips16 (PROC_LOW_ADDR (proc_desc)))
+ {
+ inst = mips_fetch_instruction (PROC_LOW_ADDR (proc_desc));
+ if ((inst & 0xf81f) == 0xe809 && (inst & 0x700) != 0x700) /* entry */
+ {
+ int reg;
+ int sreg_count = (inst >> 6) & 3;
+
+ /* Check if the ra register was pushed on the stack. */
+ reg_position = fci->frame + PROC_REG_OFFSET (proc_desc);
+ if (inst & 0x20)
+ reg_position -= MIPS_REGSIZE;
+
+ /* Check if the s0 and s1 registers were pushed on the stack. */
+ for (reg = 16; reg < sreg_count+16; reg++)
+ {
+ fci->saved_regs->regs[reg] = reg_position;
+ reg_position -= MIPS_REGSIZE;
+ }
+ }
+ }
+
/* Fill in the offsets for the registers which float_mask says
were saved. */
reg_position = fci->frame + PROC_FREG_OFFSET (proc_desc);
/* The freg_offset points to where the first *double* register
is saved. So skip to the high-order word. */
if (! GDB_TARGET_IS_MIPS64)
- reg_position += 4;
+ reg_position += MIPS_REGSIZE;
- /* FIXME! this code looks scary...
- * Looks like it's trying to do stuff with a register,
- * but .... ???
- */
+ /* Fill in the offsets for the float registers which float_mask says
+ were saved. */
for (ireg = MIPS_NUMREGS-1; float_mask; --ireg, float_mask <<= 1)
if (float_mask & 0x80000000)
{
mips_addr_bits_remove (addr)
CORE_ADDR addr;
{
- if (GDB_TARGET_IS_MIPS64
- && (addr >> 32 == (CORE_ADDR)0xffffffff)
- && (strcmp(target_shortname,"pmon")==0
- || strcmp(target_shortname,"ddb")==0
- || strcmp(target_shortname,"sim")==0))
+#if GDB_TARGET_IS_MIPS64
+ if ((addr >> 32 == (CORE_ADDR)0xffffffff)
+ && (strcmp (target_shortname,"pmon")==0
+ || strcmp (target_shortname,"ddb")==0
+ || strcmp (target_shortname,"sim")==0))
{
/* This hack is a work-around for existing boards using PMON,
the simulator, and any other 64-bit targets that doesn't have
addressing, and this masking will have to be disabled. */
addr &= (CORE_ADDR)0xffffffff;
}
+#else
+ /* Even when GDB is configured for some 32-bit targets (e.g. mips-elf),
+ BFD is configured to handle 64-bit targets, so CORE_ADDR is 64 bits.
+ So we still have to mask off useless bits from addresses. */
+ addr &= (CORE_ADDR)0xffffffff;
+#endif
return addr;
}
+void
+mips_init_frame_pc_first (fromleaf, prev)
+ int fromleaf;
+ struct frame_info *prev;
+{
+ CORE_ADDR pc, tmp;
+
+ pc = ((fromleaf) ? SAVED_PC_AFTER_CALL (prev->next) :
+ prev->next ? FRAME_SAVED_PC (prev->next) : read_pc ());
+ tmp = mips_skip_stub (pc);
+ prev->pc = tmp ? tmp : pc;
+}
+
+
CORE_ADDR
mips_frame_saved_pc(frame)
struct frame_info *frame;
static struct mips_extra_func_info temp_proc_desc;
static struct frame_saved_regs temp_saved_regs;
+/* Set a register's saved stack address in temp_saved_regs. If an address
+ has already been set for this register, do nothing; this way we will
+ only recognize the first save of a given register in a function prologue.
+ This is a helper function for mips{16,32}_heuristic_proc_desc. */
+
+static void
+set_reg_offset (regno, offset)
+ int regno;
+ CORE_ADDR offset;
+{
+ if (temp_saved_regs.regs[regno] == 0)
+ temp_saved_regs.regs[regno] = offset;
+}
+
+
/* This fencepost looks highly suspicious to me. Removing it also
seems suspicious as it could affect remote debugging across serial
lines. */
heuristic_proc_start(pc)
CORE_ADDR pc;
{
- CORE_ADDR start_pc = pc;
- CORE_ADDR fence = start_pc - heuristic_fence_post;
-
+ CORE_ADDR start_pc;
+ CORE_ADDR fence;
+ int instlen;
+ int seen_adjsp = 0;
+
+ pc = ADDR_BITS_REMOVE (pc);
+ start_pc = pc;
+ fence = start_pc - heuristic_fence_post;
if (start_pc == 0) return 0;
if (heuristic_fence_post == UINT_MAX
|| fence < VM_MIN_ADDRESS)
fence = VM_MIN_ADDRESS;
+ instlen = pc_is_mips16 (pc) ? MIPS16_INSTLEN : MIPS_INSTLEN;
+
/* search back for previous return */
- for (start_pc -= MIPS_INSTLEN; ; start_pc -= MIPS_INSTLEN) /* FIXME!! */
+ for (start_pc -= instlen; ; start_pc -= instlen)
if (start_pc < fence)
{
/* It's not clear to me why we reach this point when
else
warning("Hit heuristic-fence-post without finding");
- warning("enclosing function for address 0x%s", paddr (pc));
+ warning("enclosing function for address 0x%s", paddr_nz (pc));
if (!blurb_printed)
{
printf_filtered ("\
return 0;
}
+ else if (pc_is_mips16 (start_pc))
+ {
+ unsigned short inst;
+
+ /* On MIPS16, any one of the following is likely to be the
+ start of a function:
+ entry
+ addiu sp,-n
+ daddiu sp,-n
+ extend -n followed by 'addiu sp,+n' or 'daddiu sp,+n' */
+ inst = mips_fetch_instruction (start_pc);
+ if (((inst & 0xf81f) == 0xe809 && (inst & 0x700) != 0x700) /* entry */
+ || (inst & 0xff80) == 0x6380 /* addiu sp,-n */
+ || (inst & 0xff80) == 0xfb80 /* daddiu sp,-n */
+ || ((inst & 0xf810) == 0xf010 && seen_adjsp)) /* extend -n */
+ break;
+ else if ((inst & 0xff00) == 0x6300 /* addiu sp */
+ || (inst & 0xff00) == 0xfb00) /* daddiu sp */
+ seen_adjsp = 1;
+ else
+ seen_adjsp = 0;
+ }
else if (ABOUT_TO_RETURN(start_pc))
+ {
+ start_pc += 2 * MIPS_INSTLEN; /* skip return, and its delay slot */
break;
+ }
- start_pc += 2 * MIPS_INSTLEN; /* skip return, and its delay slot */
#if 0
/* skip nops (usually 1) 0 - is this */
while (start_pc < pc && read_memory_integer (start_pc, MIPS_INSTLEN) == 0)
return start_pc;
}
-static mips_extra_func_info_t
-heuristic_proc_desc(start_pc, limit_pc, next_frame)
+/* Fetch the immediate value from a MIPS16 instruction.
+ If the previous instruction was an EXTEND, use it to extend
+ the upper bits of the immediate value. This is a helper function
+ for mips16_heuristic_proc_desc. */
+
+static int
+mips16_get_imm (prev_inst, inst, nbits, scale, is_signed)
+ unsigned short prev_inst; /* previous instruction */
+ unsigned short inst; /* current instruction */
+ int nbits; /* number of bits in imm field */
+ int scale; /* scale factor to be applied to imm */
+ int is_signed; /* is the imm field signed? */
+{
+ int offset;
+
+ if ((prev_inst & 0xf800) == 0xf000) /* prev instruction was EXTEND? */
+ {
+ offset = ((prev_inst & 0x1f) << 11) | (prev_inst & 0x7e0);
+ if (offset & 0x8000) /* check for negative extend */
+ offset = 0 - (0x10000 - (offset & 0xffff));
+ return offset | (inst & 0x1f);
+ }
+ else
+ {
+ int max_imm = 1 << nbits;
+ int mask = max_imm - 1;
+ int sign_bit = max_imm >> 1;
+
+ offset = inst & mask;
+ if (is_signed && (offset & sign_bit))
+ offset = 0 - (max_imm - offset);
+ return offset * scale;
+ }
+}
+
+
+/* Fill in values in temp_proc_desc based on the MIPS16 instruction
+ stream from start_pc to limit_pc. */
+
+static void
+mips16_heuristic_proc_desc(start_pc, limit_pc, next_frame, sp)
CORE_ADDR start_pc, limit_pc;
struct frame_info *next_frame;
+ CORE_ADDR sp;
{
- CORE_ADDR sp = read_next_frame_reg (next_frame, SP_REGNUM);
- CORE_ADDR cur_pc;
- unsigned long frame_size;
- int has_frame_reg = 0;
- CORE_ADDR reg30 = 0; /* Value of $r30. Used by gcc for frame-pointer */
- unsigned long reg_mask = 0;
-
- if (start_pc == 0) return NULL;
- memset (&temp_proc_desc, '\0', sizeof(temp_proc_desc));
- memset (&temp_saved_regs, '\0', sizeof(struct frame_saved_regs));
- PROC_LOW_ADDR (&temp_proc_desc) = start_pc;
-
- if (start_pc + 200 < limit_pc)
- limit_pc = start_pc + 200;
- restart:
- frame_size = 0;
- for (cur_pc = start_pc; cur_pc < limit_pc; cur_pc += MIPS_INSTLEN) {
- char buf[MIPS_INSTLEN];
- unsigned long word;
- int status;
-
- status = (unsigned long) read_memory_nobpt (cur_pc, buf, MIPS_INSTLEN); /* FIXME!! */
- if (status) memory_error (status, cur_pc);
- word = (unsigned long) extract_unsigned_integer (buf, MIPS_INSTLEN); /* FIXME!! */
-
- if ((word & 0xFFFF0000) == 0x27bd0000 /* addiu $sp,$sp,-i */
- || (word & 0xFFFF0000) == 0x23bd0000 /* addi $sp,$sp,-i */
- || (word & 0xFFFF0000) == 0x67bd0000) /* daddiu $sp,$sp,-i */
- frame_size += (-word) & 0xFFFF;
- else if ((word & 0xFFE00000) == 0xafa00000 /* sw reg,offset($sp) */
- || (word & 0xFFE00000) == 0xffa00000) { /* sd reg,offset($sp) */
- int reg = (word & 0x001F0000) >> 16;
- reg_mask |= 1 << reg;
- temp_saved_regs.regs[reg] = sp + (word & 0xffff);
+ CORE_ADDR cur_pc;
+ CORE_ADDR frame_addr = 0; /* Value of $r17, used as frame pointer */
+ unsigned short prev_inst = 0; /* saved copy of previous instruction */
+ unsigned inst = 0; /* current instruction */
+ unsigned entry_inst = 0; /* the entry instruction */
+ int reg, offset;
+
+ PROC_FRAME_OFFSET(&temp_proc_desc) = 0; /* size of stack frame */
+ PROC_FRAME_ADJUST(&temp_proc_desc) = 0; /* offset of FP from SP */
+
+ for (cur_pc = start_pc; cur_pc < limit_pc; cur_pc += MIPS16_INSTLEN)
+ {
+ /* Save the previous instruction. If it's an EXTEND, we'll extract
+ the immediate offset extension from it in mips16_get_imm. */
+ prev_inst = inst;
+
+ /* Fetch and decode the instruction. */
+ inst = (unsigned short) mips_fetch_instruction (cur_pc);
+ if ((inst & 0xff00) == 0x6300 /* addiu sp */
+ || (inst & 0xff00) == 0xfb00) /* daddiu sp */
+ {
+ offset = mips16_get_imm (prev_inst, inst, 8, 8, 1);
+ if (offset < 0) /* negative stack adjustment? */
+ PROC_FRAME_OFFSET(&temp_proc_desc) -= offset;
+ else
+ /* Exit loop if a positive stack adjustment is found, which
+ usually means that the stack cleanup code in the function
+ epilogue is reached. */
+ break;
+ }
+ else if ((inst & 0xf800) == 0xd000) /* sw reg,n($sp) */
+ {
+ offset = mips16_get_imm (prev_inst, inst, 8, 4, 0);
+ reg = mips16_to_32_reg[(inst & 0x700) >> 8];
+ PROC_REG_MASK(&temp_proc_desc) |= (1 << reg);
+ set_reg_offset (reg, sp + offset);
}
- else if ((word & 0xFFFF0000) == 0x27be0000) { /* addiu $30,$sp,size */
- if ((word & 0xffff) != frame_size)
- reg30 = sp + (word & 0xffff);
- else if (!has_frame_reg) {
- unsigned alloca_adjust;
- has_frame_reg = 1;
- reg30 = read_next_frame_reg(next_frame, 30);
- alloca_adjust = (unsigned)(reg30 - (sp + (word & 0xffff)));
- if (alloca_adjust > 0) {
- /* FP > SP + frame_size. This may be because
- * of an alloca or somethings similar.
- * Fix sp to "pre-alloca" value, and try again.
- */
- sp += alloca_adjust;
- goto restart;
+ else if ((inst & 0xff00) == 0xf900) /* sd reg,n($sp) */
+ {
+ offset = mips16_get_imm (prev_inst, inst, 5, 8, 0);
+ reg = mips16_to_32_reg[(inst & 0xe0) >> 5];
+ PROC_REG_MASK(&temp_proc_desc) |= (1 << reg);
+ set_reg_offset (reg, sp + offset);
+ }
+ else if ((inst & 0xff00) == 0x6200) /* sw $ra,n($sp) */
+ {
+ offset = mips16_get_imm (prev_inst, inst, 8, 4, 0);
+ PROC_REG_MASK(&temp_proc_desc) |= (1 << RA_REGNUM);
+ set_reg_offset (RA_REGNUM, sp + offset);
+ }
+ else if ((inst & 0xff00) == 0xfa00) /* sd $ra,n($sp) */
+ {
+ offset = mips16_get_imm (prev_inst, inst, 8, 8, 0);
+ PROC_REG_MASK(&temp_proc_desc) |= (1 << RA_REGNUM);
+ set_reg_offset (RA_REGNUM, sp + offset);
+ }
+ else if (inst == 0x673d) /* move $s1, $sp */
+ {
+ frame_addr = sp;
+ PROC_FRAME_REG (&temp_proc_desc) = 17;
+ }
+ else if ((inst & 0xff00) == 0x0100) /* addiu $s1,sp,n */
+ {
+ offset = mips16_get_imm (prev_inst, inst, 8, 4, 0);
+ frame_addr = sp + offset;
+ PROC_FRAME_REG (&temp_proc_desc) = 17;
+ PROC_FRAME_ADJUST (&temp_proc_desc) = offset;
+ }
+ else if ((inst & 0xFF00) == 0xd900) /* sw reg,offset($s1) */
+ {
+ offset = mips16_get_imm (prev_inst, inst, 5, 4, 0);
+ reg = mips16_to_32_reg[(inst & 0xe0) >> 5];
+ PROC_REG_MASK(&temp_proc_desc) |= 1 << reg;
+ set_reg_offset (reg, frame_addr + offset);
+ }
+ else if ((inst & 0xFF00) == 0x7900) /* sd reg,offset($s1) */
+ {
+ offset = mips16_get_imm (prev_inst, inst, 5, 8, 0);
+ reg = mips16_to_32_reg[(inst & 0xe0) >> 5];
+ PROC_REG_MASK(&temp_proc_desc) |= 1 << reg;
+ set_reg_offset (reg, frame_addr + offset);
+ }
+ else if ((inst & 0xf81f) == 0xe809 && (inst & 0x700) != 0x700) /* entry */
+ entry_inst = inst; /* save for later processing */
+ else if ((inst & 0xf800) == 0x1800) /* jal(x) */
+ cur_pc += MIPS16_INSTLEN; /* 32-bit instruction */
+ }
+
+ /* The entry instruction is typically the first instruction in a function,
+ and it stores registers at offsets relative to the value of the old SP
+ (before the prologue). But the value of the sp parameter to this
+ function is the new SP (after the prologue has been executed). So we
+ can't calculate those offsets until we've seen the entire prologue,
+ and can calculate what the old SP must have been. */
+ if (entry_inst != 0)
+ {
+ int areg_count = (entry_inst >> 8) & 7;
+ int sreg_count = (entry_inst >> 6) & 3;
+
+ /* The entry instruction always subtracts 32 from the SP. */
+ PROC_FRAME_OFFSET(&temp_proc_desc) += 32;
+
+ /* Now we can calculate what the SP must have been at the
+ start of the function prologue. */
+ sp += PROC_FRAME_OFFSET(&temp_proc_desc);
+
+ /* Check if a0-a3 were saved in the caller's argument save area. */
+ for (reg = 4, offset = 0; reg < areg_count+4; reg++)
+ {
+ PROC_REG_MASK(&temp_proc_desc) |= 1 << reg;
+ set_reg_offset (reg, sp + offset);
+ offset += MIPS_REGSIZE;
+ }
+
+ /* Check if the ra register was pushed on the stack. */
+ offset = -4;
+ if (entry_inst & 0x20)
+ {
+ PROC_REG_MASK(&temp_proc_desc) |= 1 << RA_REGNUM;
+ set_reg_offset (RA_REGNUM, sp + offset);
+ offset -= MIPS_REGSIZE;
+ }
+
+ /* Check if the s0 and s1 registers were pushed on the stack. */
+ for (reg = 16; reg < sreg_count+16; reg++)
+ {
+ PROC_REG_MASK(&temp_proc_desc) |= 1 << reg;
+ set_reg_offset (reg, sp + offset);
+ offset -= MIPS_REGSIZE;
+ }
+ }
+}
+
+static void
+mips32_heuristic_proc_desc(start_pc, limit_pc, next_frame, sp)
+ CORE_ADDR start_pc, limit_pc;
+ struct frame_info *next_frame;
+ CORE_ADDR sp;
+{
+ CORE_ADDR cur_pc;
+ CORE_ADDR frame_addr = 0; /* Value of $r30. Used by gcc for frame-pointer */
+restart:
+ PROC_FRAME_OFFSET(&temp_proc_desc) = 0;
+ PROC_FRAME_ADJUST (&temp_proc_desc) = 0; /* offset of FP from SP */
+ for (cur_pc = start_pc; cur_pc < limit_pc; cur_pc += MIPS_INSTLEN)
+ {
+ unsigned long inst, high_word, low_word;
+ int reg;
+
+ /* Fetch the instruction. */
+ inst = (unsigned long) mips_fetch_instruction (cur_pc);
+
+ /* Save some code by pre-extracting some useful fields. */
+ high_word = (inst >> 16) & 0xffff;
+ low_word = inst & 0xffff;
+ reg = high_word & 0x1f;
+
+ if (high_word == 0x27bd /* addiu $sp,$sp,-i */
+ || high_word == 0x23bd /* addi $sp,$sp,-i */
+ || high_word == 0x67bd) /* daddiu $sp,$sp,-i */
+ {
+ if (low_word & 0x8000) /* negative stack adjustment? */
+ PROC_FRAME_OFFSET(&temp_proc_desc) += 0x10000 - low_word;
+ else
+ /* Exit loop if a positive stack adjustment is found, which
+ usually means that the stack cleanup code in the function
+ epilogue is reached. */
+ break;
+ }
+ else if ((high_word & 0xFFE0) == 0xafa0) /* sw reg,offset($sp) */
+ {
+ PROC_REG_MASK(&temp_proc_desc) |= 1 << reg;
+ set_reg_offset (reg, sp + low_word);
+ }
+ else if ((high_word & 0xFFE0) == 0xffa0) /* sd reg,offset($sp) */
+ {
+ /* Irix 6.2 N32 ABI uses sd instructions for saving $gp and $ra,
+ but the register size used is only 32 bits. Make the address
+ for the saved register point to the lower 32 bits. */
+ PROC_REG_MASK(&temp_proc_desc) |= 1 << reg;
+ set_reg_offset (reg, sp + low_word + 8 - MIPS_REGSIZE);
+ }
+ else if (high_word == 0x27be) /* addiu $30,$sp,size */
+ {
+ /* Old gcc frame, r30 is virtual frame pointer. */
+ if ((long)low_word != PROC_FRAME_OFFSET(&temp_proc_desc))
+ frame_addr = sp + low_word;
+ else if (PROC_FRAME_REG (&temp_proc_desc) == SP_REGNUM)
+ {
+ unsigned alloca_adjust;
+ PROC_FRAME_REG (&temp_proc_desc) = 30;
+ frame_addr = read_next_frame_reg(next_frame, 30);
+ alloca_adjust = (unsigned)(frame_addr - (sp + low_word));
+ if (alloca_adjust > 0)
+ {
+ /* FP > SP + frame_size. This may be because
+ * of an alloca or somethings similar.
+ * Fix sp to "pre-alloca" value, and try again.
+ */
+ sp += alloca_adjust;
+ goto restart;
+ }
+ }
+ }
+ /* move $30,$sp. With different versions of gas this will be either
+ `addu $30,$sp,$zero' or `or $30,$sp,$zero' or `daddu 30,sp,$0'.
+ Accept any one of these. */
+ else if (inst == 0x03A0F021 || inst == 0x03a0f025 || inst == 0x03a0f02d)
+ {
+ /* New gcc frame, virtual frame pointer is at r30 + frame_size. */
+ if (PROC_FRAME_REG (&temp_proc_desc) == SP_REGNUM)
+ {
+ unsigned alloca_adjust;
+ PROC_FRAME_REG (&temp_proc_desc) = 30;
+ frame_addr = read_next_frame_reg(next_frame, 30);
+ alloca_adjust = (unsigned)(frame_addr - sp);
+ if (alloca_adjust > 0)
+ {
+ /* FP > SP + frame_size. This may be because
+ * of an alloca or somethings similar.
+ * Fix sp to "pre-alloca" value, and try again.
+ */
+ sp += alloca_adjust;
+ goto restart;
}
}
}
- else if ((word & 0xFFE00000) == 0xafc00000) { /* sw reg,offset($30) */
- int reg = (word & 0x001F0000) >> 16;
- reg_mask |= 1 << reg;
- temp_saved_regs.regs[reg] = reg30 + (word & 0xffff);
+ else if ((high_word & 0xFFE0) == 0xafc0) /* sw reg,offset($30) */
+ {
+ PROC_REG_MASK(&temp_proc_desc) |= 1 << reg;
+ set_reg_offset (reg, frame_addr + low_word);
}
}
- if (has_frame_reg) {
- PROC_FRAME_REG(&temp_proc_desc) = 30;
- PROC_FRAME_OFFSET(&temp_proc_desc) = 0;
- }
- else {
- PROC_FRAME_REG(&temp_proc_desc) = SP_REGNUM;
- PROC_FRAME_OFFSET(&temp_proc_desc) = frame_size;
- }
- PROC_REG_MASK(&temp_proc_desc) = reg_mask;
- PROC_PC_REG(&temp_proc_desc) = RA_REGNUM;
- return &temp_proc_desc;
}
static mips_extra_func_info_t
-find_proc_desc (pc, next_frame)
+heuristic_proc_desc(start_pc, limit_pc, next_frame)
+ CORE_ADDR start_pc, limit_pc;
+ struct frame_info *next_frame;
+{
+ CORE_ADDR sp = read_next_frame_reg (next_frame, SP_REGNUM);
+
+ if (start_pc == 0) return NULL;
+ memset (&temp_proc_desc, '\0', sizeof(temp_proc_desc));
+ memset (&temp_saved_regs, '\0', sizeof(struct frame_saved_regs));
+ PROC_LOW_ADDR (&temp_proc_desc) = start_pc;
+ PROC_FRAME_REG (&temp_proc_desc) = SP_REGNUM;
+ PROC_PC_REG (&temp_proc_desc) = RA_REGNUM;
+
+ if (start_pc + 200 < limit_pc)
+ limit_pc = start_pc + 200;
+ if (pc_is_mips16 (start_pc))
+ mips16_heuristic_proc_desc (start_pc, limit_pc, next_frame, sp);
+ else
+ mips32_heuristic_proc_desc (start_pc, limit_pc, next_frame, sp);
+ return &temp_proc_desc;
+}
+
+static mips_extra_func_info_t
+non_heuristic_proc_desc (pc, addrptr)
CORE_ADDR pc;
- struct frame_info *next_frame;
+ CORE_ADDR *addrptr;
{
+ CORE_ADDR startaddr;
mips_extra_func_info_t proc_desc;
struct block *b = block_for_pc(pc);
struct symbol *sym;
- CORE_ADDR startaddr;
find_pc_partial_function (pc, NULL, &startaddr, NULL);
- if (b == NULL)
+ if (addrptr)
+ *addrptr = startaddr;
+ if (b == NULL || PC_IN_CALL_DUMMY (pc, 0, 0))
sym = NULL;
else
{
symbol reading. */
sym = NULL;
else
- sym = lookup_symbol (MIPS_EFI_SYMBOL_NAME, b, LABEL_NAMESPACE,
- 0, NULL);
+ sym = lookup_symbol (MIPS_EFI_SYMBOL_NAME, b, LABEL_NAMESPACE, 0, NULL);
}
/* If we never found a PDR for this function in symbol reading, then
examine prologues to find the information. */
- if (sym && ((mips_extra_func_info_t) SYMBOL_VALUE (sym))->pdr.framereg == -1)
- sym = NULL;
-
if (sym)
{
- /* IF this is the topmost frame AND
- * (this proc does not have debugging information OR
- * the PC is in the procedure prologue)
- * THEN create a "heuristic" proc_desc (by analyzing
- * the actual code) to replace the "official" proc_desc.
- */
- proc_desc = (mips_extra_func_info_t) SYMBOL_VALUE (sym);
- if (next_frame == NULL) {
- struct symtab_and_line val;
- struct symbol *proc_symbol =
- PROC_DESC_IS_DUMMY(proc_desc) ? 0 : PROC_SYMBOL(proc_desc);
-
- if (proc_symbol) {
- val = find_pc_line (BLOCK_START
- (SYMBOL_BLOCK_VALUE(proc_symbol)),
- 0);
- val.pc = val.end ? val.end : pc;
+ proc_desc = (mips_extra_func_info_t) SYMBOL_VALUE (sym);
+ if (PROC_FRAME_REG (proc_desc) == -1)
+ return NULL;
+ else
+ return proc_desc;
+ }
+ else
+ return NULL;
+}
+
+
+static mips_extra_func_info_t
+find_proc_desc (pc, next_frame)
+ CORE_ADDR pc;
+ struct frame_info *next_frame;
+{
+ mips_extra_func_info_t proc_desc;
+ CORE_ADDR startaddr;
+
+ proc_desc = non_heuristic_proc_desc (pc, &startaddr);
+
+ if (proc_desc)
+ {
+ /* IF this is the topmost frame AND
+ * (this proc does not have debugging information OR
+ * the PC is in the procedure prologue)
+ * THEN create a "heuristic" proc_desc (by analyzing
+ * the actual code) to replace the "official" proc_desc.
+ */
+ if (next_frame == NULL)
+ {
+ struct symtab_and_line val;
+ struct symbol *proc_symbol =
+ PROC_DESC_IS_DUMMY(proc_desc) ? 0 : PROC_SYMBOL(proc_desc);
+
+ if (proc_symbol)
+ {
+ val = find_pc_line (BLOCK_START
+ (SYMBOL_BLOCK_VALUE(proc_symbol)),
+ 0);
+ val.pc = val.end ? val.end : pc;
}
- if (!proc_symbol || pc < val.pc) {
- mips_extra_func_info_t found_heuristic =
- heuristic_proc_desc (PROC_LOW_ADDR (proc_desc),
- pc, next_frame);
- if (found_heuristic)
- proc_desc = found_heuristic;
+ if (!proc_symbol || pc < val.pc)
+ {
+ mips_extra_func_info_t found_heuristic =
+ heuristic_proc_desc (PROC_LOW_ADDR (proc_desc),
+ pc, next_frame);
+ if (found_heuristic)
+ proc_desc = found_heuristic;
}
}
}
struct frame_info *frame;
mips_extra_func_info_t proc_desc;
{
- return ADDR_BITS_REMOVE (read_next_frame_reg (frame,
- PROC_FRAME_REG(proc_desc)) + PROC_FRAME_OFFSET(proc_desc));
+ return ADDR_BITS_REMOVE (
+ read_next_frame_reg (frame, PROC_FRAME_REG (proc_desc)) +
+ PROC_FRAME_OFFSET (proc_desc) - PROC_FRAME_ADJUST (proc_desc));
}
mips_extra_func_info_t cached_proc_desc;
mips_frame_chain(frame)
struct frame_info *frame;
{
- mips_extra_func_info_t proc_desc;
- CORE_ADDR saved_pc = FRAME_SAVED_PC(frame);
-
- if (saved_pc == 0 || inside_entry_file (saved_pc))
- return 0;
-
- proc_desc = find_proc_desc(saved_pc, frame);
- if (!proc_desc)
- return 0;
-
- cached_proc_desc = proc_desc;
-
- /* If no frame pointer and frame size is zero, we must be at end
- of stack (or otherwise hosed). If we don't check frame size,
- we loop forever if we see a zero size frame. */
- if (PROC_FRAME_REG (proc_desc) == SP_REGNUM
- && PROC_FRAME_OFFSET (proc_desc) == 0
- /* The previous frame from a sigtramp frame might be frameless
- and have frame size zero. */
- && !frame->signal_handler_caller)
- return 0;
- else
- return get_frame_pointer (frame, proc_desc);
+ mips_extra_func_info_t proc_desc;
+ CORE_ADDR tmp;
+ CORE_ADDR saved_pc = FRAME_SAVED_PC(frame);
+
+ if (saved_pc == 0 || inside_entry_file (saved_pc))
+ return 0;
+
+ /* Check if the PC is inside a call stub. If it is, fetch the
+ PC of the caller of that stub. */
+ if ((tmp = mips_skip_stub (saved_pc)) != 0)
+ saved_pc = tmp;
+
+ /* Look up the procedure descriptor for this PC. */
+ proc_desc = find_proc_desc(saved_pc, frame);
+ if (!proc_desc)
+ return 0;
+
+ cached_proc_desc = proc_desc;
+
+ /* If no frame pointer and frame size is zero, we must be at end
+ of stack (or otherwise hosed). If we don't check frame size,
+ we loop forever if we see a zero size frame. */
+ if (PROC_FRAME_REG (proc_desc) == SP_REGNUM
+ && PROC_FRAME_OFFSET (proc_desc) == 0
+ /* The previous frame from a sigtramp frame might be frameless
+ and have frame size zero. */
+ && !frame->signal_handler_caller)
+ return 0;
+ else
+ return get_frame_pointer (frame, proc_desc);
}
void
return create_new_frame (argv[0], argv[1]);
}
-
CORE_ADDR
mips_push_arguments(nargs, args, sp, struct_return, struct_addr)
- int nargs;
- value_ptr *args;
- CORE_ADDR sp;
- int struct_return;
- CORE_ADDR struct_addr;
+ int nargs;
+ value_ptr *args;
+ CORE_ADDR sp;
+ int struct_return;
+ CORE_ADDR struct_addr;
{
- register i;
- int accumulate_size;
- struct mips_arg { char *contents; int len; int offset; };
- struct mips_arg *mips_args;
- register struct mips_arg *m_arg;
- int fake_args = 0;
- int len;
-
- /* Macro to round n up to the next a boundary (a must be a power of two) */
- #define ALIGN(n,a) (((n)+(a)-1) & ~((a)-1))
+ int argreg;
+ int float_argreg;
+ int argnum;
+ int len = 0;
+ int stack_offset = 0;
+
+ /* Macros to round N up or down to the next A boundary; A must be
+ a power of two. */
+#define ROUND_DOWN(n,a) ((n) & ~((a)-1))
+#define ROUND_UP(n,a) (((n)+(a)-1) & ~((a)-1))
/* First ensure that the stack and structure return address (if any)
- are properly aligned. */
-
- sp = ALIGN (sp, MIPS_REGSIZE);
- struct_addr = ALIGN (struct_addr, MIPS_REGSIZE);
+ are properly aligned. The stack has to be 64-bit aligned even
+ on 32-bit machines, because doubles must be 64-bit aligned. */
+ sp = ROUND_DOWN (sp, 8);
+ struct_addr = ROUND_DOWN (struct_addr, MIPS_REGSIZE);
- accumulate_size = struct_return ? MIPS_REGSIZE : 0;
-
- /* Allocate descriptors for each argument, plus some extras for the
- dummies we will create to zero-fill the holes left when we align
- arguments passed in registers that are smaller than a register. */
- mips_args =
- (struct mips_arg*) alloca ((nargs + MIPS_NUM_ARG_REGS) * sizeof (struct mips_arg));
-
- /* Build up the list of argument descriptors. */
- for (i = 0, m_arg = mips_args; i < nargs; i++, m_arg++) {
- value_ptr arg = args[i];
- len = m_arg->len = TYPE_LENGTH (VALUE_TYPE (arg));
- /* This entire mips-specific routine is because doubles must be aligned
- * on 8-byte boundaries. It still isn't quite right, because MIPS decided
- * to align 'struct {int a, b}' on 4-byte boundaries (even though this
- * breaks their varargs implementation...). A correct solution
- * requires a simulation of gcc's 'alignof' (and use of 'alignof'
- * in stdarg.h/varargs.h).
- * On the 64 bit r4000 we always pass the first four arguments
- * using eight bytes each, so that we can load them up correctly
- * in CALL_DUMMY.
- */
- if (len > 4) /* FIXME? */
- accumulate_size = ALIGN (accumulate_size, 8);
- m_arg->offset = accumulate_size;
- m_arg->contents = VALUE_CONTENTS(arg);
- if (! GDB_TARGET_IS_MIPS64)
- /* For 32-bit targets, align the next argument on a 32-bit boundary. */
- accumulate_size = ALIGN (accumulate_size + len, 4);
- else
- {
- /* The following test attempts to determine if the argument
- is being passed on the stack. But it fails account for
- floating point arguments in the EABI, which should have their
- own accumulated size separate from that for integer arguments.
- FIXME!! */
- if (accumulate_size >= MIPS_NUM_ARG_REGS * MIPS_REGSIZE)
- /* The argument is being passed on the stack, not a register,
- so adjust the size of the argument upward to account for stack
- alignment. But shouldn't we be right-aligning small arguments
- as we do below for the args-in-registers case? FIXME!! */
- accumulate_size = ALIGN (accumulate_size + len, 8);
- else
- {
- if (len < MIPS_REGSIZE)
- {
- /* The argument is being passed in a register, but is smaller
- than a register. So it it must be right-aligned in the
- register image being placed in the stack, and the rest
- of the register image must be zero-filled. */
- static char zeroes[MIPS_REGSIZE] = { 0 };
-
- /* Align the arg in the rightmost part of the 64-bit word. */
- if (TARGET_BYTE_ORDER == BIG_ENDIAN)
- m_arg->offset += MIPS_REGSIZE - len;
-
- /* Create a fake argument to zero-fill the unsused part
- of the 64-bit word. */
- ++m_arg;
- m_arg->len = MIPS_REGSIZE - len;
- m_arg->contents = zeroes;
- if (TARGET_BYTE_ORDER == BIG_ENDIAN)
- m_arg->offset = accumulate_size;
- else
- m_arg->offset = accumulate_size + len;
- ++fake_args;
- }
- accumulate_size = ALIGN (accumulate_size + len, MIPS_REGSIZE);
- }
- }
- }
- accumulate_size = ALIGN (accumulate_size, 8);
- if (accumulate_size < 4 * MIPS_REGSIZE)
- accumulate_size = 4 * MIPS_REGSIZE;
- sp -= accumulate_size;
- for (i = nargs + fake_args; m_arg--, --i >= 0; )
- write_memory(sp + m_arg->offset, m_arg->contents, m_arg->len);
+ /* Now make space on the stack for the args. We allocate more
+ than necessary for EABI, because the first few arguments are
+ passed in registers, but that's OK. */
+ for (argnum = 0; argnum < nargs; argnum++)
+ len += ROUND_UP (TYPE_LENGTH(VALUE_TYPE(args[argnum])), MIPS_REGSIZE);
+ sp -= ROUND_UP (len, 8);
+
+ /* Initialize the integer and float register pointers. */
+ argreg = A0_REGNUM;
+ float_argreg = FPA0_REGNUM;
+
+ /* the struct_return pointer occupies the first parameter-passing reg */
if (struct_return)
+ write_register (argreg++, struct_addr);
+
+ /* Now load as many as possible of the first arguments into
+ registers, and push the rest onto the stack. Loop thru args
+ from first to last. */
+ for (argnum = 0; argnum < nargs; argnum++)
{
- char buf[TARGET_PTR_BIT / HOST_CHAR_BIT];
+ char *val;
+ char valbuf[REGISTER_RAW_SIZE(A0_REGNUM)];
+ value_ptr arg = args[argnum];
+ struct type *arg_type = check_typedef (VALUE_TYPE (arg));
+ int len = TYPE_LENGTH (arg_type);
+ enum type_code typecode = TYPE_CODE (arg_type);
+
+ /* The EABI passes structures that do not fit in a register by
+ reference. In all other cases, pass the structure by value. */
+ if (MIPS_EABI && len > MIPS_REGSIZE &&
+ (typecode == TYPE_CODE_STRUCT || typecode == TYPE_CODE_UNION))
+ {
+ store_address (valbuf, MIPS_REGSIZE, VALUE_ADDRESS (arg));
+ typecode = TYPE_CODE_PTR;
+ len = MIPS_REGSIZE;
+ val = valbuf;
+ }
+ else
+ val = (char *)VALUE_CONTENTS (arg);
+
+ /* 32-bit ABIs always start floating point arguments in an
+ even-numbered floating point register. */
+ if (!GDB_TARGET_IS_MIPS64 && typecode == TYPE_CODE_FLT
+ && (float_argreg & 1))
+ float_argreg++;
+
+ /* Floating point arguments passed in registers have to be
+ treated specially. On 32-bit architectures, doubles
+ are passed in register pairs; the even register gets
+ the low word, and the odd register gets the high word.
+ On non-EABI processors, the first two floating point arguments are
+ also copied to general registers, because MIPS16 functions
+ don't use float registers for arguments. This duplication of
+ arguments in general registers can't hurt non-MIPS16 functions
+ because those registers are normally skipped. */
+ if (typecode == TYPE_CODE_FLT
+ && float_argreg <= MIPS_LAST_FP_ARG_REGNUM
+ && mips_fpu != MIPS_FPU_NONE)
+ {
+ if (!GDB_TARGET_IS_MIPS64 && len == 8)
+ {
+ int low_offset = TARGET_BYTE_ORDER == BIG_ENDIAN ? 4 : 0;
+ unsigned long regval;
+
+ /* Write the low word of the double to the even register(s). */
+ regval = extract_unsigned_integer (val+low_offset, 4);
+ write_register (float_argreg++, regval);
+ if (!MIPS_EABI)
+ write_register (argreg+1, regval);
+
+ /* Write the high word of the double to the odd register(s). */
+ regval = extract_unsigned_integer (val+4-low_offset, 4);
+ write_register (float_argreg++, regval);
+ if (!MIPS_EABI)
+ {
+ write_register (argreg, regval);
+ argreg += 2;
+ }
- store_address (buf, sizeof buf, struct_addr);
- write_memory (sp, buf, sizeof buf);
+ }
+ else
+ {
+ /* This is a floating point value that fits entirely
+ in a single register. */
+ CORE_ADDR regval = extract_address (val, len);
+ write_register (float_argreg++, regval);
+ if (!MIPS_EABI)
+ {
+ write_register (argreg, regval);
+ argreg += GDB_TARGET_IS_MIPS64 ? 1 : 2;
+ }
+ }
+ }
+ else
+ {
+ /* Copy the argument to general registers or the stack in
+ register-sized pieces. Large arguments are split between
+ registers and stack. */
+ /* Note: structs whose size is not a multiple of MIPS_REGSIZE
+ are treated specially: Irix cc passes them in registers
+ where gcc sometimes puts them on the stack. For maximum
+ compatibility, we will put them in both places. */
+
+ int odd_sized_struct = ((len > MIPS_REGSIZE) &&
+ (len % MIPS_REGSIZE != 0));
+ while (len > 0)
+ {
+ int partial_len = len < MIPS_REGSIZE ? len : MIPS_REGSIZE;
+
+ if (argreg > MIPS_LAST_ARG_REGNUM || odd_sized_struct)
+ {
+ /* Write this portion of the argument to the stack. */
+ int longword_offset;
+
+ longword_offset = 0;
+ if (TARGET_BYTE_ORDER == BIG_ENDIAN)
+ if (MIPS_REGSIZE == 8 &&
+ (typecode == TYPE_CODE_INT ||
+ typecode == TYPE_CODE_PTR ||
+ typecode == TYPE_CODE_FLT) && len <= 4)
+ longword_offset = 4;
+ else if ((typecode == TYPE_CODE_STRUCT ||
+ typecode == TYPE_CODE_UNION) &&
+ TYPE_LENGTH (arg_type) < MIPS_REGSIZE)
+ longword_offset = MIPS_REGSIZE - len;
+
+ write_memory (sp + stack_offset + longword_offset,
+ val, partial_len);
+ }
+
+ /* Note!!! This is NOT an else clause.
+ Odd sized structs may go thru BOTH paths. */
+ if (argreg <= MIPS_LAST_ARG_REGNUM)
+ {
+ CORE_ADDR regval = extract_address (val, partial_len);
+
+ /* A non-floating-point argument being passed in a
+ general register. If a struct or union, and if
+ the remaining length is smaller than the register
+ size, we have to adjust the register value on
+ big endian targets.
+
+ It does not seem to be necessary to do the
+ same for integral types.
+
+ Also don't do this adjustment on EABI targets. */
+
+ if (!MIPS_EABI &&
+ TARGET_BYTE_ORDER == BIG_ENDIAN &&
+ partial_len < MIPS_REGSIZE &&
+ (typecode == TYPE_CODE_STRUCT ||
+ typecode == TYPE_CODE_UNION))
+ regval <<= ((MIPS_REGSIZE - partial_len) *
+ TARGET_CHAR_BIT);
+
+ write_register (argreg, regval);
+ argreg++;
+
+ /* If this is the old ABI, prevent subsequent floating
+ point arguments from being passed in floating point
+ registers. */
+ if (!MIPS_EABI)
+ float_argreg = MIPS_LAST_FP_ARG_REGNUM + 1;
+ }
+
+ len -= partial_len;
+ val += partial_len;
+
+ /* The offset onto the stack at which we will start
+ copying parameters (after the registers are used up)
+ begins at (4 * MIPS_REGSIZE) in the old ABI. This
+ leaves room for the "home" area for register parameters.
+
+ In the new EABI, the 8 register parameters do not
+ have "home" stack space reserved for them, so the
+ stack offset does not get incremented until after
+ we have used up the 8 parameter registers. */
+ if (!(MIPS_EABI && argnum < 8))
+ stack_offset += ROUND_UP (partial_len, MIPS_REGSIZE);
+ }
+ }
}
+
+ /* Set the return address register to point to the entry
+ point of the program, where a breakpoint lies in wait. */
+ write_register (RA_REGNUM, CALL_DUMMY_ADDRESS());
+
+ /* Return adjusted stack pointer. */
return sp;
}
-void
+static void
mips_push_register(CORE_ADDR *sp, int regno)
{
char buffer[MAX_REGISTER_RAW_SIZE];
* Saved D18 (i.e. F19, F18)
* ...
* Saved D0 (i.e. F1, F0)
- * CALL_DUMMY (subroutine stub; see tm-mips.h)
- * Parameter build area (not yet implemented)
+ * Argument build area and stack arguments written via mips_push_arguments
* (low memory)
*/
/* Save special registers (PC, MMHI, MMLO, FPC_CSR) */
- write_register (PUSH_FP_REGNUM, sp);
PROC_FRAME_REG(proc_desc) = PUSH_FP_REGNUM;
PROC_FRAME_OFFSET(proc_desc) = 0;
+ PROC_FRAME_ADJUST(proc_desc) = 0;
mips_push_register (&sp, PC_REGNUM);
mips_push_register (&sp, HI_REGNUM);
mips_push_register (&sp, LO_REGNUM);
if (PROC_FREG_MASK(proc_desc) & (1 << ireg))
mips_push_register (&sp, ireg + FP0_REGNUM);
- /* Update the stack pointer. Set the procedure's starting and ending
- addresses to point to the place on the stack where we'll be writing the
- dummy code (in mips_push_arguments). */
+ /* Update the frame pointer for the call dummy and the stack pointer.
+ Set the procedure's starting and ending addresses to point to the
+ call dummy address at the entry point. */
+ write_register (PUSH_FP_REGNUM, old_sp);
write_register (SP_REGNUM, sp);
- PROC_LOW_ADDR(proc_desc) = sp - CALL_DUMMY_SIZE + CALL_DUMMY_START_OFFSET;
- PROC_HIGH_ADDR(proc_desc) = sp;
+ PROC_LOW_ADDR(proc_desc) = CALL_DUMMY_ADDRESS();
+ PROC_HIGH_ADDR(proc_desc) = CALL_DUMMY_ADDRESS() + 4;
SET_PROC_DESC_IS_DUMMY(proc_desc);
PROC_PC_REG(proc_desc) = RA_REGNUM;
}
write_register (PC_REGNUM, FRAME_SAVED_PC(frame));
if (frame->saved_regs == NULL)
mips_find_saved_regs (frame);
- if (proc_desc)
+ for (regnum = 0; regnum < NUM_REGS; regnum++)
{
- for (regnum = MIPS_NUMREGS; --regnum >= 0; )
- if (PROC_REG_MASK(proc_desc) & (1 << regnum))
- write_register (regnum,
- read_memory_integer (frame->saved_regs->regs[regnum],
- MIPS_REGSIZE));
- for (regnum = MIPS_NUMREGS; --regnum >= 0; )
- if (PROC_FREG_MASK(proc_desc) & (1 << regnum))
- write_register (regnum + FP0_REGNUM,
- read_memory_integer (frame->saved_regs->regs[regnum + FP0_REGNUM], MIPS_REGSIZE));
+ if (regnum != SP_REGNUM && regnum != PC_REGNUM
+ && frame->saved_regs->regs[regnum])
+ write_register (regnum,
+ read_memory_integer (frame->saved_regs->regs[regnum],
+ MIPS_REGSIZE));
}
write_register (SP_REGNUM, new_sp);
flush_cached_frames ();
return;
}
- /* If an even floating pointer register, also print as double. */
- if (regnum >= FP0_REGNUM && regnum < FP0_REGNUM+MIPS_NUMREGS
+ /* If an even floating point register, also print as double. */
+ if (TYPE_CODE (REGISTER_VIRTUAL_TYPE (regnum)) == TYPE_CODE_FLT
&& !((regnum-FP0_REGNUM) & 1))
- {
- char dbuffer[MAX_REGISTER_RAW_SIZE];
+ if (REGISTER_RAW_SIZE(regnum) == 4) /* this would be silly on MIPS64 */
+ {
+ char dbuffer[2 * MAX_REGISTER_RAW_SIZE];
- read_relative_register_raw_bytes (regnum, dbuffer);
- read_relative_register_raw_bytes (regnum+1, dbuffer+4); /* FIXME!! */
-#ifdef REGISTER_CONVERT_TO_TYPE
- REGISTER_CONVERT_TO_TYPE(regnum, builtin_type_double, dbuffer);
-#endif
- printf_filtered ("(d%d: ", regnum-FP0_REGNUM);
- val_print (builtin_type_double, dbuffer, 0,
- gdb_stdout, 0, 1, 0, Val_pretty_default);
- printf_filtered ("); ");
- }
+ read_relative_register_raw_bytes (regnum, dbuffer);
+ read_relative_register_raw_bytes (regnum+1, dbuffer+MIPS_REGSIZE);
+ REGISTER_CONVERT_TO_TYPE (regnum, builtin_type_double, dbuffer);
+
+ printf_filtered ("(d%d: ", regnum-FP0_REGNUM);
+ val_print (builtin_type_double, dbuffer, 0,
+ gdb_stdout, 0, 1, 0, Val_pretty_default);
+ printf_filtered ("); ");
+ }
fputs_filtered (reg_names[regnum], gdb_stdout);
/* The problem with printing numeric register names (r26, etc.) is that
/* If virtual format is floating, print it that way. */
if (TYPE_CODE (REGISTER_VIRTUAL_TYPE (regnum)) == TYPE_CODE_FLT)
- val_print (REGISTER_VIRTUAL_TYPE (regnum), raw_buffer, 0,
- gdb_stdout, 0, 1, 0, Val_pretty_default);
+ if (REGISTER_RAW_SIZE(regnum) == 8)
+ { /* show 8-byte floats as float AND double: */
+ int offset = 4 * (TARGET_BYTE_ORDER == BIG_ENDIAN);
+
+ printf_filtered (" (float) ");
+ val_print (builtin_type_float, raw_buffer + offset, 0,
+ gdb_stdout, 0, 1, 0, Val_pretty_default);
+ printf_filtered (", (double) ");
+ val_print (builtin_type_double, raw_buffer, 0,
+ gdb_stdout, 0, 1, 0, Val_pretty_default);
+ }
+ else
+ val_print (REGISTER_VIRTUAL_TYPE (regnum), raw_buffer, 0,
+ gdb_stdout, 0, 1, 0, Val_pretty_default);
/* Else print as integer in hex. */
else
print_scalar_formatted (raw_buffer, REGISTER_VIRTUAL_TYPE (regnum),
'x', 0, gdb_stdout);
}
-/* Replacement for generic do_registers_info. */
+/* Replacement for generic do_registers_info.
+ Print regs in pretty columns. */
+
+static int
+do_fp_register_row (regnum)
+ int regnum;
+{ /* do values for FP (float) regs */
+ char raw_buffer[2] [REGISTER_RAW_SIZE(FP0_REGNUM)];
+ char dbl_buffer[2 * REGISTER_RAW_SIZE(FP0_REGNUM)];
+ /* use HI and LO to control the order of combining two flt regs */
+ int HI = (TARGET_BYTE_ORDER == BIG_ENDIAN);
+ int LO = (TARGET_BYTE_ORDER != BIG_ENDIAN);
+ double doub, flt1, flt2; /* doubles extracted from raw hex data */
+ int inv1, inv2, inv3;
+
+ /* Get the data in raw format. */
+ if (read_relative_register_raw_bytes (regnum, raw_buffer[HI]))
+ error ("can't read register %d (%s)", regnum, reg_names[regnum]);
+ if (REGISTER_RAW_SIZE(regnum) == 4)
+ {
+ /* 4-byte registers: we can fit two registers per row. */
+ /* Also print every pair of 4-byte regs as an 8-byte double. */
+ if (read_relative_register_raw_bytes (regnum + 1, raw_buffer[LO]))
+ error ("can't read register %d (%s)",
+ regnum + 1, reg_names[regnum + 1]);
+
+ /* copy the two floats into one double, and unpack both */
+ memcpy (dbl_buffer, raw_buffer, sizeof(dbl_buffer));
+ flt1 = unpack_double (builtin_type_float, raw_buffer[HI], &inv1);
+ flt2 = unpack_double (builtin_type_float, raw_buffer[LO], &inv2);
+ doub = unpack_double (builtin_type_double, dbl_buffer, &inv3);
+
+ printf_filtered (inv1 ? " %-5s: <invalid float>" :
+ " %-5s%-17.9g", reg_names[regnum], flt1);
+ printf_filtered (inv2 ? " %-5s: <invalid float>" :
+ " %-5s%-17.9g", reg_names[regnum + 1], flt2);
+ printf_filtered (inv3 ? " dbl: <invalid double>\n" :
+ " dbl: %-24.17g\n", doub);
+ /* may want to do hex display here (future enhancement) */
+ regnum +=2;
+ }
+ else
+ { /* eight byte registers: print each one as float AND as double. */
+ int offset = 4 * (TARGET_BYTE_ORDER == BIG_ENDIAN);
+
+ memcpy (dbl_buffer, raw_buffer[HI], sizeof(dbl_buffer));
+ flt1 = unpack_double (builtin_type_float,
+ &raw_buffer[HI][offset], &inv1);
+ doub = unpack_double (builtin_type_double, dbl_buffer, &inv3);
+
+ printf_filtered (inv1 ? " %-5s: <invalid float>" :
+ " %-5s flt: %-17.9g", reg_names[regnum], flt1);
+ printf_filtered (inv3 ? " dbl: <invalid double>\n" :
+ " dbl: %-24.17g\n", doub);
+ /* may want to do hex display here (future enhancement) */
+ regnum++;
+ }
+ return regnum;
+}
+
+/* Print a row's worth of GP (int) registers, with name labels above */
+
+static int
+do_gp_register_row (regnum)
+ int regnum;
+{ /* do values for GP (int) regs */
+ char raw_buffer[REGISTER_RAW_SIZE(0)];
+ int ncols = MIPS_REGSIZE == 8 ? 4 : 8; /* display cols per row */
+ int col, byte, start_regnum = regnum;
+
+ /* For GP registers, we print a separate row of names above the vals */
+ printf_filtered (" ");
+ for (col = 0; col < ncols && regnum < NUM_REGS; regnum++)
+ {
+ if (*reg_names[regnum] == '\0')
+ continue; /* unused register */
+ if (TYPE_CODE (REGISTER_VIRTUAL_TYPE (regnum)) == TYPE_CODE_FLT)
+ break; /* end the row: reached FP register */
+ printf_filtered (MIPS_REGSIZE == 8 ? "%17s" : "%9s",
+ reg_names[regnum]);
+ col++;
+ }
+ printf_filtered (start_regnum < MIPS_NUMREGS ? "\n R%-4d" : "\n ",
+ start_regnum); /* print the R0 to R31 names */
+
+ regnum = start_regnum; /* go back to start of row */
+ /* now print the values in hex, 4 or 8 to the row */
+ for (col = 0; col < ncols && regnum < NUM_REGS; regnum++)
+ {
+ if (*reg_names[regnum] == '\0')
+ continue; /* unused register */
+ if (TYPE_CODE (REGISTER_VIRTUAL_TYPE (regnum)) == TYPE_CODE_FLT)
+ break; /* end row: reached FP register */
+ /* OK: get the data in raw format. */
+ if (read_relative_register_raw_bytes (regnum, raw_buffer))
+ error ("can't read register %d (%s)", regnum, reg_names[regnum]);
+ /* Now print the register value in hex, endian order. */
+ if (TARGET_BYTE_ORDER == BIG_ENDIAN)
+ for (byte = 0; byte < REGISTER_RAW_SIZE (regnum); byte++)
+ printf_filtered ("%02x", (unsigned char) raw_buffer[byte]);
+ else
+ for (byte = REGISTER_RAW_SIZE (regnum) - 1; byte >= 0; byte--)
+ printf_filtered ("%02x", (unsigned char) raw_buffer[byte]);
+ printf_filtered (" ");
+ col++;
+ }
+ if (col > 0) /* ie. if we actually printed anything... */
+ printf_filtered ("\n");
+
+ return regnum;
+}
+
+/* MIPS_DO_REGISTERS_INFO(): called by "info register" command */
void
mips_do_registers_info (regnum, fpregs)
int regnum;
int fpregs;
{
- if (regnum != -1)
+ if (regnum != -1) /* do one specified register */
{
if (*(reg_names[regnum]) == '\0')
error ("Not a valid register for the current processor type");
mips_print_register (regnum, 0);
printf_filtered ("\n");
}
- else
+ else /* do all (or most) registers */
{
- int did_newline = 0;
-
- for (regnum = 0; regnum < NUM_REGS; )
- {
- if (((!fpregs) && regnum >= FP0_REGNUM && regnum <= FCRIR_REGNUM)
- || *(reg_names[regnum]) == '\0')
- {
- regnum++;
- continue;
- }
- mips_print_register (regnum, 1);
- regnum++;
- printf_filtered ("; ");
- did_newline = 0;
- if ((regnum & 3) == 0)
- {
- printf_filtered ("\n");
- did_newline = 1;
- }
- }
- if (!did_newline)
- printf_filtered ("\n");
+ regnum = 0;
+ while (regnum < NUM_REGS)
+ if (TYPE_CODE(REGISTER_VIRTUAL_TYPE (regnum)) == TYPE_CODE_FLT)
+ if (fpregs) /* true for "INFO ALL-REGISTERS" command */
+ regnum = do_fp_register_row (regnum); /* FP regs */
+ else
+ regnum += MIPS_NUMREGS; /* skip floating point regs */
+ else
+ regnum = do_gp_register_row (regnum); /* GP (int) regs */
}
}
{
char buf[MIPS_INSTLEN];
+ /* There is no branch delay slot on MIPS16. */
+ if (pc_is_mips16 (pc))
+ return 0;
+
if (target_read_memory (pc, buf, MIPS_INSTLEN) != 0)
/* If error reading memory, guess that it is not a delayed branch. */
return 0;
return is_delayed ((unsigned long)extract_unsigned_integer (buf, MIPS_INSTLEN));
}
-/* To skip prologues, I use this predicate. Returns either PC itself
- if the code at PC does not look like a function prologue; otherwise
- returns an address that (if we're lucky) follows the prologue. If
- LENIENT, then we must skip everything which is involved in setting
- up the frame (it's OK to skip more, just so long as we don't skip
- anything which might clobber the registers which are being saved.
- We must skip more in the case where part of the prologue is in the
- delay slot of a non-prologue instruction). */
-CORE_ADDR
-mips_skip_prologue (pc, lenient)
- CORE_ADDR pc;
+/* Skip the PC past function prologue instructions (32-bit version).
+ This is a helper function for mips_skip_prologue. */
+
+static CORE_ADDR
+mips32_skip_prologue (pc, lenient)
+ CORE_ADDR pc; /* starting PC to search from */
int lenient;
{
t_inst inst;
- unsigned offset;
+ CORE_ADDR end_pc;
int seen_sp_adjust = 0;
int load_immediate_bytes = 0;
- CORE_ADDR post_prologue_pc;
-
- /* See if we can determine the end of the prologue via the symbol table.
- If so, then return either PC, or the PC after the prologue, whichever
- is greater. */
-
- post_prologue_pc = after_prologue (pc, NULL);
-
- if (post_prologue_pc != 0)
- return max (pc, post_prologue_pc);
-
- /* Can't determine prologue from the symbol table, need to examine
- instructions. */
/* Skip the typical prologue instructions. These are the stack adjustment
instruction and the instructions that save registers on the stack
or in the gcc frame. */
- for (offset = 0; offset < 100; offset += MIPS_INSTLEN)
+ for (end_pc = pc + 100; pc < end_pc; pc += MIPS_INSTLEN)
{
- char buf[MIPS_INSTLEN];
- int status;
+ unsigned long high_word;
- status = read_memory_nobpt (pc + offset, buf, MIPS_INSTLEN);
- if (status)
- memory_error (status, pc + offset);
- inst = (unsigned long)extract_unsigned_integer (buf, MIPS_INSTLEN);
+ inst = mips_fetch_instruction (pc);
+ high_word = (inst >> 16) & 0xffff;
#if 0
if (lenient && is_delayed (inst))
continue;
#endif
- /* Must add cases for 64-bit operations. FIXME!! */
- if ((inst & 0xffff0000) == 0x27bd0000) /* addiu $sp,$sp,offset */
+ if (high_word == 0x27bd /* addiu $sp,$sp,offset */
+ || high_word == 0x67bd) /* daddiu $sp,$sp,offset */
seen_sp_adjust = 1;
else if (inst == 0x03a1e823 || /* subu $sp,$sp,$at */
inst == 0x03a8e823) /* subu $sp,$sp,$t0 */
seen_sp_adjust = 1;
- else if ((inst & 0xFFE00000) == 0xAFA00000 && (inst & 0x001F0000))
- continue; /* sw reg,n($sp) */
- /* reg != $zero */
+ else if (((inst & 0xFFE00000) == 0xAFA00000 /* sw reg,n($sp) */
+ || (inst & 0xFFE00000) == 0xFFA00000) /* sd reg,n($sp) */
+ && (inst & 0x001F0000)) /* reg != $zero */
+ continue;
+
else if ((inst & 0xFFE00000) == 0xE7A00000) /* swc1 freg,n($sp) */
continue;
else if ((inst & 0xF3E00000) == 0xA3C00000 && (inst & 0x001F0000))
continue; /* reg != $zero */
/* move $s8,$sp. With different versions of gas this will be either
- `addu $s8,$sp,$zero' or `or $s8,$sp,$zero'. Accept either. */
- else if (inst == 0x03A0F021 || inst == 0x03a0f025)
+ `addu $s8,$sp,$zero' or `or $s8,$sp,$zero' or `daddu s8,sp,$0'.
+ Accept any one of these. */
+ else if (inst == 0x03A0F021 || inst == 0x03a0f025 || inst == 0x03a0f02d)
continue;
else if ((inst & 0xFF9F07FF) == 0x00800021) /* move reg,$a0-$a3 */
continue;
- else if ((inst & 0xffff0000) == 0x3c1c0000) /* lui $gp,n */
+ else if (high_word == 0x3c1c) /* lui $gp,n */
continue;
- else if ((inst & 0xffff0000) == 0x279c0000) /* addiu $gp,$gp,n */
+ else if (high_word == 0x279c) /* addiu $gp,$gp,n */
continue;
else if (inst == 0x0399e021 /* addu $gp,$gp,$t9 */
|| inst == 0x033ce021) /* addu $gp,$t9,$gp */
instruction was seen. */
else if (!seen_sp_adjust)
{
- if ((inst & 0xffff0000) == 0x3c010000 || /* lui $at,n */
- (inst & 0xffff0000) == 0x3c080000) /* lui $t0,n */
+ if (high_word == 0x3c01 || /* lui $at,n */
+ high_word == 0x3c08) /* lui $t0,n */
{
load_immediate_bytes += MIPS_INSTLEN; /* FIXME!! */
continue;
}
- else if ((inst & 0xffff0000) == 0x34210000 || /* ori $at,$at,n */
- (inst & 0xffff0000) == 0x35080000 || /* ori $t0,$t0,n */
- (inst & 0xffff0000) == 0x34010000 || /* ori $at,$zero,n */
- (inst & 0xffff0000) == 0x34080000) /* ori $t0,$zero,n */
+ else if (high_word == 0x3421 || /* ori $at,$at,n */
+ high_word == 0x3508 || /* ori $t0,$t0,n */
+ high_word == 0x3401 || /* ori $at,$zero,n */
+ high_word == 0x3408) /* ori $t0,$zero,n */
{
load_immediate_bytes += MIPS_INSTLEN; /* FIXME!! */
continue;
skipped some load immediate instructions. Undo the skipping
if the load immediate was not followed by a stack adjustment. */
if (load_immediate_bytes && !seen_sp_adjust)
- offset -= load_immediate_bytes;
- return pc + offset;
+ pc -= load_immediate_bytes;
+ return pc;
+}
+
+/* Skip the PC past function prologue instructions (16-bit version).
+ This is a helper function for mips_skip_prologue. */
+
+static CORE_ADDR
+mips16_skip_prologue (pc, lenient)
+ CORE_ADDR pc; /* starting PC to search from */
+ int lenient;
+{
+ CORE_ADDR end_pc;
+ int extend_bytes = 0;
+ int prev_extend_bytes;
+
+ /* Table of instructions likely to be found in a function prologue. */
+ static struct
+ {
+ unsigned short inst;
+ unsigned short mask;
+ } table[] =
+ {
+ { 0x6300, 0xff00 }, /* addiu $sp,offset */
+ { 0xfb00, 0xff00 }, /* daddiu $sp,offset */
+ { 0xd000, 0xf800 }, /* sw reg,n($sp) */
+ { 0xf900, 0xff00 }, /* sd reg,n($sp) */
+ { 0x6200, 0xff00 }, /* sw $ra,n($sp) */
+ { 0xfa00, 0xff00 }, /* sd $ra,n($sp) */
+ { 0x673d, 0xffff }, /* move $s1,sp */
+ { 0xd980, 0xff80 }, /* sw $a0-$a3,n($s1) */
+ { 0x6704, 0xff1c }, /* move reg,$a0-$a3 */
+ { 0xe809, 0xf81f }, /* entry pseudo-op */
+ { 0x0100, 0xff00 }, /* addiu $s1,$sp,n */
+ { 0, 0 } /* end of table marker */
+ };
+
+ /* Skip the typical prologue instructions. These are the stack adjustment
+ instruction and the instructions that save registers on the stack
+ or in the gcc frame. */
+ for (end_pc = pc + 100; pc < end_pc; pc += MIPS16_INSTLEN)
+ {
+ unsigned short inst;
+ int i;
+
+ inst = mips_fetch_instruction (pc);
+
+ /* Normally we ignore an extend instruction. However, if it is
+ not followed by a valid prologue instruction, we must adjust
+ the pc back over the extend so that it won't be considered
+ part of the prologue. */
+ if ((inst & 0xf800) == 0xf000) /* extend */
+ {
+ extend_bytes = MIPS16_INSTLEN;
+ continue;
+ }
+ prev_extend_bytes = extend_bytes;
+ extend_bytes = 0;
+
+ /* Check for other valid prologue instructions besides extend. */
+ for (i = 0; table[i].mask != 0; i++)
+ if ((inst & table[i].mask) == table[i].inst) /* found, get out */
+ break;
+ if (table[i].mask != 0) /* it was in table? */
+ continue; /* ignore it */
+ else /* non-prologue */
+ {
+ /* Return the current pc, adjusted backwards by 2 if
+ the previous instruction was an extend. */
+ return pc - prev_extend_bytes;
+ }
+ }
+ return pc;
+}
+
+/* To skip prologues, I use this predicate. Returns either PC itself
+ if the code at PC does not look like a function prologue; otherwise
+ returns an address that (if we're lucky) follows the prologue. If
+ LENIENT, then we must skip everything which is involved in setting
+ up the frame (it's OK to skip more, just so long as we don't skip
+ anything which might clobber the registers which are being saved.
+ We must skip more in the case where part of the prologue is in the
+ delay slot of a non-prologue instruction). */
+
+CORE_ADDR
+mips_skip_prologue (pc, lenient)
+ CORE_ADDR pc;
+ int lenient;
+{
+ /* See if we can determine the end of the prologue via the symbol table.
+ If so, then return either PC, or the PC after the prologue, whichever
+ is greater. */
+
+ CORE_ADDR post_prologue_pc = after_prologue (pc, NULL);
+
+ if (post_prologue_pc != 0)
+ return max (pc, post_prologue_pc);
+
+ /* Can't determine prologue from the symbol table, need to examine
+ instructions. */
+
+ if (pc_is_mips16 (pc))
+ return mips16_skip_prologue (pc, lenient);
+ else
+ return mips32_skip_prologue (pc, lenient);
}
#if 0
-/* The lenient prologue stuff should be superceded by the code in
+/* The lenient prologue stuff should be superseded by the code in
init_extra_frame_info which looks to see whether the stores mentioned
in the proc_desc have actually taken place. */
{
int regnum;
int offset = 0;
+ int len = TYPE_LENGTH (valtype);
regnum = 2;
if (TYPE_CODE (valtype) == TYPE_CODE_FLT
- && (mips_fpu == MIPS_FPU_DOUBLE
- || (mips_fpu == MIPS_FPU_SINGLE && TYPE_LENGTH (valtype) <= 4))) /* FIXME!! */
+ && (mips_fpu == MIPS_FPU_DOUBLE
+ || (mips_fpu == MIPS_FPU_SINGLE && len <= MIPS_REGSIZE)))
regnum = FP0_REGNUM;
- if (TARGET_BYTE_ORDER == BIG_ENDIAN
- && TYPE_CODE (valtype) != TYPE_CODE_FLT
- && TYPE_LENGTH (valtype) < REGISTER_RAW_SIZE (regnum))
- offset = REGISTER_RAW_SIZE (regnum) - TYPE_LENGTH (valtype);
-
- memcpy (valbuf, regbuf + REGISTER_BYTE (regnum) + offset,
- TYPE_LENGTH (valtype));
-#ifdef REGISTER_CONVERT_TO_TYPE
- REGISTER_CONVERT_TO_TYPE(regnum, valtype, valbuf);
-#endif
+ if (TARGET_BYTE_ORDER == BIG_ENDIAN)
+ { /* "un-left-justify" the value from the register */
+ if (len < REGISTER_RAW_SIZE (regnum))
+ offset = REGISTER_RAW_SIZE (regnum) - len;
+ if (len > REGISTER_RAW_SIZE (regnum) && /* odd-size structs */
+ len < REGISTER_RAW_SIZE (regnum) * 2 &&
+ (TYPE_CODE (valtype) == TYPE_CODE_STRUCT ||
+ TYPE_CODE (valtype) == TYPE_CODE_UNION))
+ offset = 2 * REGISTER_RAW_SIZE (regnum) - len;
+ }
+ memcpy (valbuf, regbuf + REGISTER_BYTE (regnum) + offset, len);
+ REGISTER_CONVERT_TO_TYPE (regnum, valtype, valbuf);
}
/* Given a return value in `regbuf' with a type `valtype',
char *valbuf;
{
int regnum;
+ int offset = 0;
+ int len = TYPE_LENGTH (valtype);
char raw_buffer[MAX_REGISTER_RAW_SIZE];
regnum = 2;
if (TYPE_CODE (valtype) == TYPE_CODE_FLT
- && (mips_fpu == MIPS_FPU_DOUBLE
- || (mips_fpu == MIPS_FPU_SINGLE && TYPE_LENGTH (valtype) <= 4))) /* FIXME!! */
+ && (mips_fpu == MIPS_FPU_DOUBLE
+ || (mips_fpu == MIPS_FPU_SINGLE && len <= MIPS_REGSIZE)))
regnum = FP0_REGNUM;
- memcpy(raw_buffer, valbuf, TYPE_LENGTH (valtype));
-
-#ifdef REGISTER_CONVERT_FROM_TYPE
+ if (TARGET_BYTE_ORDER == BIG_ENDIAN)
+ { /* "left-justify" the value in the register */
+ if (len < REGISTER_RAW_SIZE (regnum))
+ offset = REGISTER_RAW_SIZE (regnum) - len;
+ if (len > REGISTER_RAW_SIZE (regnum) && /* odd-size structs */
+ len < REGISTER_RAW_SIZE (regnum) * 2 &&
+ (TYPE_CODE (valtype) == TYPE_CODE_STRUCT ||
+ TYPE_CODE (valtype) == TYPE_CODE_UNION))
+ offset = 2 * REGISTER_RAW_SIZE (regnum) - len;
+ }
+ memcpy(raw_buffer + offset, valbuf, len);
REGISTER_CONVERT_FROM_TYPE(regnum, valtype, raw_buffer);
-#endif
-
- write_register_bytes(REGISTER_BYTE (regnum), raw_buffer, TYPE_LENGTH (valtype));
+ write_register_bytes(REGISTER_BYTE (regnum), raw_buffer,
+ len > REGISTER_RAW_SIZE (regnum) ?
+ len : REGISTER_RAW_SIZE (regnum));
}
/* Exported procedure: Is PC in the signal trampoline code */
bfd_vma memaddr;
disassemble_info *info;
{
+ mips_extra_func_info_t proc_desc;
+
+ /* Search for the function containing this address. Set the low bit
+ of the address when searching, in case we were given an even address
+ that is the start of a 16-bit function. If we didn't do this,
+ the search would fail because the symbol table says the function
+ starts at an odd address, i.e. 1 byte past the given address. */
+ memaddr = ADDR_BITS_REMOVE (memaddr);
+ proc_desc = non_heuristic_proc_desc (MAKE_MIPS16_ADDR (memaddr), NULL);
+
+ /* Make an attempt to determine if this is a 16-bit function. If
+ the procedure descriptor exists and the address therein is odd,
+ it's definitely a 16-bit function. Otherwise, we have to just
+ guess that if the address passed in is odd, it's 16-bits. */
+ if (proc_desc)
+ info->mach = pc_is_mips16 (PROC_LOW_ADDR (proc_desc)) ? 16 : 0;
+ else
+ info->mach = pc_is_mips16 (memaddr) ? 16 : 0;
+
+ /* Round down the instruction address to the appropriate boundary. */
+ memaddr &= (info->mach == 16 ? ~1 : ~3);
+
+ /* Call the appropriate disassembler based on the target endian-ness. */
if (TARGET_BYTE_ORDER == BIG_ENDIAN)
return print_insn_big_mips (memaddr, info);
else
return print_insn_little_mips (memaddr, info);
}
+/* This function implements the BREAKPOINT_FROM_PC macro. It uses the program
+ counter value to determine whether a 16- or 32-bit breakpoint should be
+ used. It returns a pointer to a string of bytes that encode a breakpoint
+ instruction, stores the length of the string to *lenptr, and adjusts pc
+ (if necessary) to point to the actual memory location where the
+ breakpoint should be inserted. */
+
+unsigned char *mips_breakpoint_from_pc (pcptr, lenptr)
+ CORE_ADDR *pcptr;
+ int *lenptr;
+{
+ if (TARGET_BYTE_ORDER == BIG_ENDIAN)
+ {
+ if (pc_is_mips16 (*pcptr))
+ {
+ static char mips16_big_breakpoint[] = MIPS16_BIG_BREAKPOINT;
+ *pcptr = UNMAKE_MIPS16_ADDR (*pcptr);
+ *lenptr = sizeof(mips16_big_breakpoint);
+ return mips16_big_breakpoint;
+ }
+ else
+ {
+ static char big_breakpoint[] = BIG_BREAKPOINT;
+ static char pmon_big_breakpoint[] = PMON_BIG_BREAKPOINT;
+ static char idt_big_breakpoint[] = IDT_BIG_BREAKPOINT;
+
+ *lenptr = sizeof(big_breakpoint);
+
+ if (strcmp (target_shortname, "mips") == 0)
+ return idt_big_breakpoint;
+ else if (strcmp (target_shortname, "ddb") == 0
+ || strcmp (target_shortname, "pmon") == 0
+ || strcmp (target_shortname, "lsi") == 0)
+ return pmon_big_breakpoint;
+ else
+ return big_breakpoint;
+ }
+ }
+ else
+ {
+ if (pc_is_mips16 (*pcptr))
+ {
+ static char mips16_little_breakpoint[] = MIPS16_LITTLE_BREAKPOINT;
+ *pcptr = UNMAKE_MIPS16_ADDR (*pcptr);
+ *lenptr = sizeof(mips16_little_breakpoint);
+ return mips16_little_breakpoint;
+ }
+ else
+ {
+ static char little_breakpoint[] = LITTLE_BREAKPOINT;
+ static char pmon_little_breakpoint[] = PMON_LITTLE_BREAKPOINT;
+ static char idt_little_breakpoint[] = IDT_LITTLE_BREAKPOINT;
+
+ *lenptr = sizeof(little_breakpoint);
+
+ if (strcmp (target_shortname, "mips") == 0)
+ return idt_little_breakpoint;
+ else if (strcmp (target_shortname, "ddb") == 0
+ || strcmp (target_shortname, "pmon") == 0
+ || strcmp (target_shortname, "lsi") == 0)
+ return pmon_little_breakpoint;
+ else
+ return little_breakpoint;
+ }
+ }
+}
+
+/* Test whether the PC points to the return instruction at the
+ end of a function. This implements the ABOUT_TO_RETURN macro. */
+
+int
+mips_about_to_return (pc)
+ CORE_ADDR pc;
+{
+ if (pc_is_mips16 (pc))
+ /* This mips16 case isn't necessarily reliable. Sometimes the compiler
+ generates a "jr $ra"; other times it generates code to load
+ the return address from the stack to an accessible register (such
+ as $a3), then a "jr" using that register. This second case
+ is almost impossible to distinguish from an indirect jump
+ used for switch statements, so we don't even try. */
+ return mips_fetch_instruction (pc) == 0xe820; /* jr $ra */
+ else
+ return mips_fetch_instruction (pc) == 0x3e00008; /* jr $ra */
+}
+
+
+/* If PC is in a mips16 call or return stub, return the address of the target
+ PC, which is either the callee or the caller. There are several
+ cases which must be handled:
+
+ * If the PC is in __mips16_ret_{d,s}f, this is a return stub and the
+ target PC is in $31 ($ra).
+ * If the PC is in __mips16_call_stub_{1..10}, this is a call stub
+ and the target PC is in $2.
+ * If the PC at the start of __mips16_call_stub_{s,d}f_{0..10}, i.e.
+ before the jal instruction, this is effectively a call stub
+ and the the target PC is in $2. Otherwise this is effectively
+ a return stub and the target PC is in $18.
+
+ See the source code for the stubs in gcc/config/mips/mips16.S for
+ gory details.
+
+ This function implements the SKIP_TRAMPOLINE_CODE macro.
+*/
+
+CORE_ADDR
+mips_skip_stub (pc)
+ CORE_ADDR pc;
+{
+ char *name;
+ CORE_ADDR start_addr;
+
+ /* Find the starting address and name of the function containing the PC. */
+ if (find_pc_partial_function (pc, &name, &start_addr, NULL) == 0)
+ return 0;
+
+ /* If the PC is in __mips16_ret_{d,s}f, this is a return stub and the
+ target PC is in $31 ($ra). */
+ if (strcmp (name, "__mips16_ret_sf") == 0
+ || strcmp (name, "__mips16_ret_df") == 0)
+ return read_register (RA_REGNUM);
+
+ if (strncmp (name, "__mips16_call_stub_", 19) == 0)
+ {
+ /* If the PC is in __mips16_call_stub_{1..10}, this is a call stub
+ and the target PC is in $2. */
+ if (name[19] >= '0' && name[19] <= '9')
+ return read_register (2);
+
+ /* If the PC at the start of __mips16_call_stub_{s,d}f_{0..10}, i.e.
+ before the jal instruction, this is effectively a call stub
+ and the the target PC is in $2. Otherwise this is effectively
+ a return stub and the target PC is in $18. */
+ else if (name[19] == 's' || name[19] == 'd')
+ {
+ if (pc == start_addr)
+ {
+ /* Check if the target of the stub is a compiler-generated
+ stub. Such a stub for a function bar might have a name
+ like __fn_stub_bar, and might look like this:
+ mfc1 $4,$f13
+ mfc1 $5,$f12
+ mfc1 $6,$f15
+ mfc1 $7,$f14
+ la $1,bar (becomes a lui/addiu pair)
+ jr $1
+ So scan down to the lui/addi and extract the target
+ address from those two instructions. */
+
+ CORE_ADDR target_pc = read_register (2);
+ t_inst inst;
+ int i;
+
+ /* See if the name of the target function is __fn_stub_*. */
+ if (find_pc_partial_function (target_pc, &name, NULL, NULL) == 0)
+ return target_pc;
+ if (strncmp (name, "__fn_stub_", 10) != 0
+ && strcmp (name, "etext") != 0
+ && strcmp (name, "_etext") != 0)
+ return target_pc;
+
+ /* Scan through this _fn_stub_ code for the lui/addiu pair.
+ The limit on the search is arbitrarily set to 20
+ instructions. FIXME. */
+ for (i = 0, pc = 0; i < 20; i++, target_pc += MIPS_INSTLEN)
+ {
+ inst = mips_fetch_instruction (target_pc);
+ if ((inst & 0xffff0000) == 0x3c010000) /* lui $at */
+ pc = (inst << 16) & 0xffff0000; /* high word */
+ else if ((inst & 0xffff0000) == 0x24210000) /* addiu $at */
+ return pc | (inst & 0xffff); /* low word */
+ }
+
+ /* Couldn't find the lui/addui pair, so return stub address. */
+ return target_pc;
+ }
+ else
+ /* This is the 'return' part of a call stub. The return
+ address is in $r18. */
+ return read_register (18);
+ }
+ }
+ return 0; /* not a stub */
+}
+
+
+/* Return non-zero if the PC is inside a call thunk (aka stub or trampoline).
+ This implements the IN_SOLIB_CALL_TRAMPOLINE macro. */
+
+int
+mips_in_call_stub (pc, name)
+ CORE_ADDR pc;
+ char *name;
+{
+ CORE_ADDR start_addr;
+
+ /* Find the starting address of the function containing the PC. If the
+ caller didn't give us a name, look it up at the same time. */
+ if (find_pc_partial_function (pc, name ? NULL : &name, &start_addr, NULL) == 0)
+ return 0;
+
+ if (strncmp (name, "__mips16_call_stub_", 19) == 0)
+ {
+ /* If the PC is in __mips16_call_stub_{1..10}, this is a call stub. */
+ if (name[19] >= '0' && name[19] <= '9')
+ return 1;
+ /* If the PC at the start of __mips16_call_stub_{s,d}f_{0..10}, i.e.
+ before the jal instruction, this is effectively a call stub. */
+ else if (name[19] == 's' || name[19] == 'd')
+ return pc == start_addr;
+ }
+
+ return 0; /* not a stub */
+}
+
+
+/* Return non-zero if the PC is inside a return thunk (aka stub or trampoline).
+ This implements the IN_SOLIB_RETURN_TRAMPOLINE macro. */
+
+int
+mips_in_return_stub (pc, name)
+ CORE_ADDR pc;
+ char *name;
+{
+ CORE_ADDR start_addr;
+
+ /* Find the starting address of the function containing the PC. */
+ if (find_pc_partial_function (pc, NULL, &start_addr, NULL) == 0)
+ return 0;
+
+ /* If the PC is in __mips16_ret_{d,s}f, this is a return stub. */
+ if (strcmp (name, "__mips16_ret_sf") == 0
+ || strcmp (name, "__mips16_ret_df") == 0)
+ return 1;
+
+ /* If the PC is in __mips16_call_stub_{s,d}f_{0..10} but not at the start,
+ i.e. after the jal instruction, this is effectively a return stub. */
+ if (strncmp (name, "__mips16_call_stub_", 19) == 0
+ && (name[19] == 's' || name[19] == 'd')
+ && pc != start_addr)
+ return 1;
+
+ return 0; /* not a stub */
+}
+
+
+/* Return non-zero if the PC is in a library helper function that should
+ be ignored. This implements the IGNORE_HELPER_CALL macro. */
+
+int
+mips_ignore_helper (pc)
+ CORE_ADDR pc;
+{
+ char *name;
+
+ /* Find the starting address and name of the function containing the PC. */
+ if (find_pc_partial_function (pc, &name, NULL, NULL) == 0)
+ return 0;
+
+ /* If the PC is in __mips16_ret_{d,s}f, this is a library helper function
+ that we want to ignore. */
+ return (strcmp (name, "__mips16_ret_sf") == 0
+ || strcmp (name, "__mips16_ret_df") == 0);
+}
+
+
void
_initialize_mips_tdep ()
{
c = add_show_from_set (c, &showlist);
c->function.sfunc = mips_show_fpu_command;
+#ifndef MIPS_DEFAULT_FPU_TYPE
mips_fpu = MIPS_FPU_DOUBLE;
mips_fpu_string = strsave ("double");
+#else
+ mips_fpu = MIPS_DEFAULT_FPU_TYPE;
+ switch (mips_fpu)
+ {
+ case MIPS_FPU_DOUBLE: mips_fpu_string = strsave ("double"); break;
+ case MIPS_FPU_SINGLE: mips_fpu_string = strsave ("single"); break;
+ case MIPS_FPU_NONE: mips_fpu_string = strsave ("none"); break;
+ }
+#endif
c = add_set_cmd ("processor", class_support, var_string_noescape,
(char *) &tmp_mips_processor_type,
projects / deliverable / binutils-gdb.git / blobdiff