#include "annotate.h"
#include "regcache.h"
#include "gdb_assert.h"
+#include "dummy-frame.h"
/* Prototypes for exported functions. */
-static void generic_call_dummy_register_unwind (struct frame_info *frame,
- void **cache,
- int regnum,
- int *optimized,
- enum lval_type *lval,
- CORE_ADDR *addrp,
- int *realnum,
- void *raw_buffer);
static void frame_saved_regs_register_unwind (struct frame_info *frame,
void **cache,
int regnum,
}
-/*
- * GENERIC DUMMY FRAMES
- *
- * The following code serves to maintain the dummy stack frames for
- * inferior function calls (ie. when gdb calls into the inferior via
- * call_function_by_hand). This code saves the machine state before
- * the call in host memory, so we must maintain an independent stack
- * and keep it consistant etc. I am attempting to make this code
- * generic enough to be used by many targets.
- *
- * The cheapest and most generic way to do CALL_DUMMY on a new target
- * is probably to define CALL_DUMMY to be empty, CALL_DUMMY_LENGTH to
- * zero, and CALL_DUMMY_LOCATION to AT_ENTRY. Then you must remember
- * to define PUSH_RETURN_ADDRESS, because no call instruction will be
- * being executed by the target. Also FRAME_CHAIN_VALID as
- * generic_{file,func}_frame_chain_valid and FIX_CALL_DUMMY as
- * generic_fix_call_dummy. */
-
-/* Dummy frame. This saves the processor state just prior to setting
- up the inferior function call. Older targets save the registers
- on the target stack (but that really slows down function calls). */
-
-struct dummy_frame
-{
- struct dummy_frame *next;
-
- CORE_ADDR pc;
- CORE_ADDR fp;
- CORE_ADDR sp;
- CORE_ADDR top;
- struct regcache *regcache;
-
- /* Address range of the call dummy code. Look for PC in the range
- [LO..HI) (after allowing for DECR_PC_AFTER_BREAK). */
- CORE_ADDR call_lo;
- CORE_ADDR call_hi;
-};
-
-static struct dummy_frame *dummy_frame_stack = NULL;
-
-/* Function: find_dummy_frame(pc, fp, sp)
-
- Search the stack of dummy frames for one matching the given PC and
- FP/SP. Unlike PC_IN_CALL_DUMMY, this function doesn't need to
- adjust for DECR_PC_AFTER_BREAK. This is because it is only legal
- to call this function after the PC has been adjusted. */
-
-static struct regcache *
-generic_find_dummy_frame (CORE_ADDR pc, CORE_ADDR fp)
-{
- struct dummy_frame *dummyframe;
-
- for (dummyframe = dummy_frame_stack; dummyframe != NULL;
- dummyframe = dummyframe->next)
- {
- /* Does the PC fall within the dummy frame's breakpoint
- instruction. If not, discard this one. */
- if (!(pc >= dummyframe->call_lo && pc < dummyframe->call_hi))
- continue;
- /* Does the FP match? */
- if (dummyframe->top != 0)
- {
- /* If the target architecture explicitly saved the
- top-of-stack before the inferior function call, assume
- that that same architecture will always pass in an FP
- (frame base) value that eactly matches that saved TOS.
- Don't check the saved SP and SP as they can lead to false
- hits. */
- if (fp != dummyframe->top)
- continue;
- }
- else
- {
- /* An older target that hasn't explicitly or implicitly
- saved the dummy frame's top-of-stack. Try matching the
- FP against the saved SP and FP. NOTE: If you're trying
- to fix a problem with GDB not correctly finding a dummy
- frame, check the comments that go with FRAME_ALIGN() and
- SAVE_DUMMY_FRAME_TOS(). */
- if (fp != dummyframe->fp && fp != dummyframe->sp)
- continue;
- }
- /* The FP matches this dummy frame. */
- return dummyframe->regcache;
- }
-
- return 0;
-}
-
-char *
-deprecated_generic_find_dummy_frame (CORE_ADDR pc, CORE_ADDR fp)
-{
- struct regcache *regcache = generic_find_dummy_frame (pc, fp);
- if (regcache == NULL)
- return NULL;
- return deprecated_grub_regcache_for_registers (regcache);
-}
-
-/* Function: pc_in_call_dummy (pc, sp, fp)
-
- Return true if the PC falls in a dummy frame created by gdb for an
- inferior call. The code below which allows DECR_PC_AFTER_BREAK is
- for infrun.c, which may give the function a PC without that
- subtracted out. */
-
-int
-generic_pc_in_call_dummy (CORE_ADDR pc, CORE_ADDR sp, CORE_ADDR fp)
-{
- struct dummy_frame *dummyframe;
- for (dummyframe = dummy_frame_stack;
- dummyframe != NULL;
- dummyframe = dummyframe->next)
- {
- if ((pc >= dummyframe->call_lo)
- && (pc < dummyframe->call_hi + DECR_PC_AFTER_BREAK))
- return 1;
- }
- return 0;
-}
-
-/* Function: read_register_dummy
- Find a saved register from before GDB calls a function in the inferior */
-
-CORE_ADDR
-deprecated_read_register_dummy (CORE_ADDR pc, CORE_ADDR fp, int regno)
-{
- struct regcache *dummy_regs = generic_find_dummy_frame (pc, fp);
-
- if (dummy_regs)
- {
- /* NOTE: cagney/2002-08-12: Replaced a call to
- regcache_raw_read_as_address() with a call to
- regcache_cooked_read_unsigned(). The old, ...as_address
- function was eventually calling extract_unsigned_integer (via
- extract_address) to unpack the registers value. The below is
- doing an unsigned extract so that it is functionally
- equivalent. The read needs to be cooked as, otherwise, it
- will never correctly return the value of a register in the
- [NUM_REGS .. NUM_REGS+NUM_PSEUDO_REGS) range. */
- ULONGEST val;
- regcache_cooked_read_unsigned (dummy_regs, regno, &val);
- return val;
- }
- else
- return 0;
-}
-
-/* Save all the registers on the dummy frame stack. Most ports save the
- registers on the target stack. This results in lots of unnecessary memory
- references, which are slow when debugging via a serial line. Instead, we
- save all the registers internally, and never write them to the stack. The
- registers get restored when the called function returns to the entry point,
- where a breakpoint is laying in wait. */
-
-void
-generic_push_dummy_frame (void)
-{
- struct dummy_frame *dummy_frame;
- CORE_ADDR fp = (get_current_frame ())->frame;
-
- /* check to see if there are stale dummy frames,
- perhaps left over from when a longjump took us out of a
- function that was called by the debugger */
-
- dummy_frame = dummy_frame_stack;
- while (dummy_frame)
- if (INNER_THAN (dummy_frame->fp, fp)) /* stale -- destroy! */
- {
- dummy_frame_stack = dummy_frame->next;
- regcache_xfree (dummy_frame->regcache);
- xfree (dummy_frame);
- dummy_frame = dummy_frame_stack;
- }
- else
- dummy_frame = dummy_frame->next;
-
- dummy_frame = xmalloc (sizeof (struct dummy_frame));
- dummy_frame->regcache = regcache_xmalloc (current_gdbarch);
-
- dummy_frame->pc = read_pc ();
- dummy_frame->sp = read_sp ();
- dummy_frame->top = 0;
- dummy_frame->fp = fp;
- regcache_cpy (dummy_frame->regcache, current_regcache);
- dummy_frame->next = dummy_frame_stack;
- dummy_frame_stack = dummy_frame;
-}
-
-void
-generic_save_dummy_frame_tos (CORE_ADDR sp)
-{
- dummy_frame_stack->top = sp;
-}
-
-/* Record the upper/lower bounds on the address of the call dummy. */
-
-void
-generic_save_call_dummy_addr (CORE_ADDR lo, CORE_ADDR hi)
-{
- dummy_frame_stack->call_lo = lo;
- dummy_frame_stack->call_hi = hi;
-}
-
-/* Restore the machine state from either the saved dummy stack or a
- real stack frame. */
-
-void
-generic_pop_current_frame (void (*popper) (struct frame_info * frame))
-{
- struct frame_info *frame = get_current_frame ();
-
- if (PC_IN_CALL_DUMMY (frame->pc, frame->frame, frame->frame))
- generic_pop_dummy_frame ();
- else
- (*popper) (frame);
-}
-
-/* Function: pop_dummy_frame
- Restore the machine state from a saved dummy stack frame. */
-
-void
-generic_pop_dummy_frame (void)
-{
- struct dummy_frame *dummy_frame = dummy_frame_stack;
-
- /* FIXME: what if the first frame isn't the right one, eg..
- because one call-by-hand function has done a longjmp into another one? */
-
- if (!dummy_frame)
- error ("Can't pop dummy frame!");
- dummy_frame_stack = dummy_frame->next;
- regcache_cpy (current_regcache, dummy_frame->regcache);
- flush_cached_frames ();
-
- regcache_xfree (dummy_frame->regcache);
- xfree (dummy_frame);
-}
-
/* Function: frame_chain_valid
Returns true for a user frame or a call_function_by_hand dummy frame,
and false for the CRT0 start-up frame. Purpose is to terminate backtrace */
&& !inside_entry_func ((fi)->pc));
}
-/* Function: fix_call_dummy
- Stub function. Generic dummy frames typically do not need to fix
- the frame being created */
-
-void
-generic_fix_call_dummy (char *dummy, CORE_ADDR pc, CORE_ADDR fun, int nargs,
- struct value **args, struct type *type, int gcc_p)
-{
- return;
-}
-
-/* Given a call-dummy dummy-frame, return the registers. Here the
- register value is taken from the local copy of the register buffer. */
-
-static void
-generic_call_dummy_register_unwind (struct frame_info *frame, void **cache,
- int regnum, int *optimized,
- enum lval_type *lvalp, CORE_ADDR *addrp,
- int *realnum, void *bufferp)
-{
- gdb_assert (frame != NULL);
- gdb_assert (PC_IN_CALL_DUMMY (frame->pc, frame->frame, frame->frame));
-
- /* Describe the register's location. Generic dummy frames always
- have the register value in an ``expression''. */
- *optimized = 0;
- *lvalp = not_lval;
- *addrp = 0;
- *realnum = -1;
-
- /* If needed, find and return the value of the register. */
- if (bufferp != NULL)
- {
- struct regcache *registers;
-#if 1
- /* Get the address of the register buffer that contains all the
- saved registers for this dummy frame. Cache that address. */
- registers = (*cache);
- if (registers == NULL)
- {
- registers = generic_find_dummy_frame (frame->pc, frame->frame);
- (*cache) = registers;
- }
-#else
- /* Get the address of the register buffer that contains the
- saved registers and then extract the value from that. */
- registers = generic_find_dummy_frame (frame->pc, frame->frame);
-#endif
- gdb_assert (registers != NULL);
- /* Return the actual value. */
- /* Use the regcache_cooked_read() method so that it, on the fly,
- constructs either a raw or pseudo register from the raw
- register cache. */
- regcache_cooked_read (registers, regnum, bufferp);
- }
-}
-
/* Return the register saved in the simplistic ``saved_regs'' cache.
If the value isn't here AND a value is needed, try the next inner
most frame. */
projects / deliverable / binutils-gdb.git / blobdiff