From 4f36d4ab734add92c54ed67f2ec1a7e571d060eb Mon Sep 17 00:00:00 2001 From: David Edelsohn Date: Fri, 2 Jun 1995 18:29:46 +0000 Subject: [PATCH] * arc-tdep.c (arc_bfd_mach_type): New static global. (codestream_fill): Handle byte order differences. (setup_prologue_scan): Don't read stdarg function's "sub sp,sp,N". (arc_get_frame_setup): Read it here. (arc_frame_saved_pc): And here. (arc_print_insn): New function. (arc_set_cpu_type): Set arc_bfd_mach_type. Don't set tm_print_insn. (_initialize_arc_tdep): Set tm_print_insn to arc_print_insn. --- gdb/ChangeLog | 13 ++++++ gdb/arc-tdep.c | 116 +++++++++++++++++++++++++++++++++++++------------ 2 files changed, 101 insertions(+), 28 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 9a1fe24613..e0390fb000 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,16 @@ +start-sanitize-arc +Fri Jun 2 11:17:23 1995 Doug Evans + + * arc-tdep.c (arc_bfd_mach_type): New static global. + (codestream_fill): Handle byte order differences. + (setup_prologue_scan): Don't read stdarg function's "sub sp,sp,N". + (arc_get_frame_setup): Read it here. + (arc_frame_saved_pc): And here. + (arc_print_insn): New function. + (arc_set_cpu_type): Set arc_bfd_mach_type. Don't set tm_print_insn. + (_initialize_arc_tdep): Set tm_print_insn to arc_print_insn. +end-sanitize-arc + Wed May 31 12:04:01 1995 J.T. Conklin * nlm/{configure.in, Makefile.in}: Converted to use autoconf. diff --git a/gdb/arc-tdep.c b/gdb/arc-tdep.c index e76aa93770..c684f0b73e 100644 --- a/gdb/arc-tdep.c +++ b/gdb/arc-tdep.c @@ -27,6 +27,7 @@ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include "gdbcmd.h" /* Current CPU, set with the "set cpu" command. */ +static int arc_bfd_mach_type; char *arc_cpu_type; char *tmp_arc_cpu_type; @@ -53,7 +54,8 @@ int debug_pipeline_p; #define OPMASK 0xf8000000 -/* Instruction field accessor macros. */ +/* Instruction field accessor macros. + See the Programmer's Reference Manual. */ #define X_OP(i) (((i) >> 27) & 0x1f) #define X_A(i) (((i) >> 21) & 0x3f) #define X_B(i) (((i) >> 15) & 0x3f) @@ -108,14 +110,25 @@ codestream_fill (peek_flag) codestream_next_addr += CODESTREAM_BUFSIZ * sizeof (codestream_buf[0]); codestream_off = 0; codestream_cnt = CODESTREAM_BUFSIZ; - /* FIXME: need to handle byte order differences. */ read_memory (codestream_addr, (char *) codestream_buf, CODESTREAM_BUFSIZ * sizeof (codestream_buf[0])); + /* FIXME: check return code? */ + + /* Handle byte order differences. */ + if (HOST_BYTE_ORDER != TARGET_BYTE_ORDER) + { + register unsigned int i, j, n = sizeof (codestream_buf[0]); + register char tmp, *p; + for (i = 0, p = (char *) codestream_buf; i < CODESTREAM_BUFSIZ; + ++i, p += n) + for (j = 0; j < n / 2; ++j) + tmp = p[j], p[j] = p[n - 1 - j], p[n - 1 - j] = tmp; + } if (peek_flag) - return (codestream_peek()); + return codestream_peek (); else - return (codestream_get()); + return codestream_get (); } static void @@ -126,10 +139,12 @@ codestream_seek (place) codestream_next_addr *= CODESTREAM_BUFSIZ; codestream_cnt = 0; codestream_fill (1); - while (codestream_tell() != place) + while (codestream_tell () != place) codestream_get (); } +/* This function is currently unused but leave in for now. */ + static void codestream_read (buf, count) unsigned int *buf; @@ -142,8 +157,7 @@ codestream_read (buf, count) *p++ = codestream_get (); } -/* Set up prologue scanning and return the first insn, - not including the "sub sp,sp,32" of a stdarg function. */ +/* Set up prologue scanning and return the first insn. */ static unsigned int setup_prologue_scan (pc) @@ -154,12 +168,6 @@ setup_prologue_scan (pc) codestream_seek (pc); insn = codestream_get (); - /* The authority for what appears here is the home-grown ABI. */ - - /* First insn may be "sub sp,sp,32" if stdarg fn. */ - if (insn == BUILD_INSN (10, SP_REGNUM, SP_REGNUM, SHIMM_REGNUM, 32)) - insn = codestream_get (); - return insn; } @@ -176,17 +184,30 @@ arc_get_frame_setup (pc) { unsigned int insn; /* Size of frame or -1 if unrecognizable prologue. */ - int n = -1; + int frame_size = -1; + /* An initial "sub sp,sp,N" may or may not be for a stdarg fn. */ + int maybe_stdarg_decr = -1; insn = setup_prologue_scan (pc); + /* The authority for what appears here is the home-grown ABI. + The most recent version is 1.2. */ + + /* First insn may be "sub sp,sp,N" if stdarg fn. */ + if ((insn & BUILD_INSN (-1, -1, -1, -1, 0)) + == BUILD_INSN (10, SP_REGNUM, SP_REGNUM, SHIMM_REGNUM, 0)) + { + maybe_stdarg_decr = X_D (insn); + insn = codestream_get (); + } + if ((insn & BUILD_INSN (-1, 0, -1, -1, -1)) /* st blink,[sp,4] */ == BUILD_INSN (2, 0, SP_REGNUM, BLINK_REGNUM, 4)) { insn = codestream_get (); /* Frame may not be necessary, even though blink is saved. At least this is something we recognize. */ - n = 0; + frame_size = 0; } if ((insn & BUILD_INSN (-1, 0, -1, -1, -1)) /* st fp,[sp] */ @@ -197,18 +218,18 @@ arc_get_frame_setup (pc) != BUILD_INSN (12, FP_REGNUM, SP_REGNUM, SP_REGNUM, 0)) return -1; - /* Check for stack adjustment sub sp,sp,nnn. */ + /* Check for stack adjustment sub sp,sp,N. */ insn = codestream_peek (); if ((insn & BUILD_INSN (-1, -1, -1, 0, 0)) == BUILD_INSN (10, SP_REGNUM, SP_REGNUM, 0, 0)) { if (LIMM_P (X_C (insn))) - n = codestream_get (); + frame_size = codestream_get (); else if (SHIMM_P (X_C (insn))) - n = X_D (insn); + frame_size = X_D (insn); else return -1; - if (n < 0) + if (frame_size < 0) return -1; codestream_get (); @@ -222,11 +243,20 @@ arc_get_frame_setup (pc) /* Frameless fn. */ else { - n = 0; + frame_size = 0; } } - return n; + /* If we found a "sub sp,sp,N" and nothing else, it may or may not be a + stdarg fn. The stdarg decrement is not treated as part of the frame size, + so we have a dilemma: what do we return? For now, if we get a + "sub sp,sp,N" and nothing else assume this isn't a stdarg fn. One way + to fix this completely would be to add a bit to the function descriptor + that says the function is a stdarg function. */ + + if (frame_size < 0 && maybe_stdarg_decr > 0) + return maybe_stdarg_decr; + return frame_size; } /* Given a pc value, skip it forward past the function prologue by @@ -283,13 +313,21 @@ arc_frame_saved_pc (frame) return ARC_PC_TO_REAL_ADDRESS (read_memory_integer (FRAME_FP (frame) + 4, 4)); } - /* If the first insn is "st blink,[sp,4]" we can get blink from there. + /* The authority for what appears here is the home-grown ABI. + The most recent version is 1.2. */ + + insn = setup_prologue_scan (func_start); + + /* First insn may be "sub sp,sp,N" if stdarg fn. */ + if ((insn & BUILD_INSN (-1, -1, -1, -1, 0)) + == BUILD_INSN (10, SP_REGNUM, SP_REGNUM, SHIMM_REGNUM, 0)) + insn = codestream_get (); + + /* If the next insn is "st blink,[sp,4]" we can get blink from there. Otherwise this is a leaf function and we can use blink. Note that this still allows for the case where a leaf function saves/clobbers/ restores blink. */ - insn = setup_prologue_scan (func_start); - if ((insn & BUILD_INSN (-1, 0, -1, -1, -1)) /* st blink,[sp,4] */ != BUILD_INSN (2, 0, SP_REGNUM, BLINK_REGNUM, 4)) return ARC_PC_TO_REAL_ADDRESS (read_register (BLINK_REGNUM)); @@ -574,6 +612,30 @@ get_longjmp_target(pc) } #endif /* GET_LONGJMP_TARGET */ +/* Disassemble one instruction. */ + +static int +arc_print_insn (vma, info) + bfd_vma vma; + disassemble_info *info; +{ + static int current_mach; + static int current_endian; + static disassembler_ftype current_disasm; + + if (current_disasm == NULL + || arc_bfd_mach_type != current_mach + || TARGET_BYTE_ORDER != current_endian) + { + current_mach = arc_bfd_mach_type; + current_endian = TARGET_BYTE_ORDER; + current_disasm = arc_get_disassembler (current_mach, + current_endian == BIG_ENDIAN); + } + + return (*current_disasm) (vma, info); +} + /* Command to set cpu type. */ void @@ -627,8 +689,7 @@ arc_set_cpu_type (str) if (strcasecmp (str, arc_cpu_type_table[i].name) == 0) { arc_cpu_type = str; - tm_print_insn = arc_get_disassembler (arc_cpu_type_table[i].value, - TARGET_BYTE_ORDER == BIG_ENDIAN); + arc_bfd_mach_type = arc_cpu_type_table[i].value; return 1; } } @@ -680,6 +741,5 @@ A negative value disables the timer.", &setlist); c = add_show_from_set (c, &showlist); - /* FIXME: must be done after for now. */ - tm_print_insn = arc_get_disassembler (bfd_mach_arc_base, 1 /*FIXME*/); + tm_print_insn = arc_print_insn; } -- 2.34.1