From 4dbe5f8d3cf7861d1e524f9a49a0d66ee17b7def Mon Sep 17 00:00:00 2001 From: Jeff Law Date: Wed, 14 May 1997 22:04:28 +0000 Subject: [PATCH] * mn10200-tdep.c (mn10200_analyze_prologue): Update prologue comments to reflect current reality. Gross attempt at handling out of line prologues. --- gdb/ChangeLog | 4 ++ gdb/mn10200-tdep.c | 207 +++++++++++++++++++++++++++++++++++++++++++++++++---- 2 files changed, 199 insertions(+), 12 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 5e83a5e..1aa5fc8 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,5 +1,9 @@ Wed May 14 08:58:55 1997 Jeffrey A Law (law@cygnus.com) + * mn10200-tdep.c (mn10200_analyze_prologue): Update prologue comments + to reflect current reality. Gross attempt at handling out of + line prologues. + * mn10200-tdep.c (mn10200_skip_prologue): Don't look at the debug symbols to find the end of the prologue. * mn10300-tdep.c (mn10300_skip_prologue): Likewise. diff --git a/gdb/mn10200-tdep.c b/gdb/mn10200-tdep.c index 11fade4..6300373 100644 --- a/gdb/mn10200-tdep.c +++ b/gdb/mn10200-tdep.c @@ -38,22 +38,26 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ mov sp,fp add ,sp Register saves for d2, d3, a1, a2 as needed. Saves start - at fp - and work towards higher addresses. Note - that the saves are actually done off the stack pointer - in the prologue! This makes for smaller code and easier - prologue scanning as the displacement fields will never + at fp - + and work towards higher + addresses. Note that the saves are actually done off the stack + pointer in the prologue! This makes for smaller code and easier + prologue scanning as the displacement fields will unlikely be more than 8 bits! Without frame pointer: add ,sp Register saves for d2, d3, a1, a2 as needed. Saves start - at sp and work towards higher addresses. + at sp + and work towards higher addresses. + Out of line prologue: + add ,sp -- optional + jsr __prologue + add ,sp -- optional + + The stack pointer remains constant throughout the life of most + functions. As a result the compiler will usually omit the + frame pointer, so we must handle frame pointerless functions. */ - One day we might keep the stack pointer constant, that won't - change the code for prologues, but it will make the frame - pointerless case much more common. */ - /* Analyze the prologue to determine where registers are saved, the end of the prologue, etc etc. Return the end of the prologue scanned. @@ -102,6 +106,7 @@ mn10200_analyze_prologue (fi, pc) unsigned char buf[4]; int status; char *name; + int out_of_line_prologue = 0; /* Use the PC in the frame if it's provided to look up the start of this function. */ @@ -302,10 +307,188 @@ mn10200_analyze_prologue (fi, pc) return addr; } } - else + + /* Now see if we have a call to __prologue for an out of line + prologue. */ + status = target_read_memory (addr, buf, 2); + if (status != 0) + return addr; + + /* First check for 16bit pc-relative call to __prologue. */ + if (buf[0] == 0xfd) { - if (fi && fi->next == NULL && (fi->status & MY_FRAME_IN_SP)) - fi->frame = read_sp (); + CORE_ADDR temp; + status = target_read_memory (addr + 1, buf, 2); + if (status != 0) + { + if (fi && fi->next == NULL && (fi->status & MY_FRAME_IN_SP)) + fi->frame = read_sp (); + return addr; + } + + /* Get the PC this instruction will branch to. */ + temp = (extract_signed_integer (buf, 2) + addr) & 0xffffff; + + /* Get the name of the function at the target address. */ + status = find_pc_partial_function (temp, &name, NULL, NULL); + if (status == 0) + { + if (fi && fi->next == NULL && (fi->status & MY_FRAME_IN_SP)) + fi->frame = read_sp (); + return addr; + } + + /* Note if it is an out of line prologue. */ + out_of_line_prologue = (strcmp (name, "__prologue") == 0); + + /* This sucks up 3 bytes of instruction space. */ + if (out_of_line_prologue) + addr += 3; + + if (addr >= stop) + { + if (fi && fi->next == NULL) + { + fi->stack_size -= 16; + fi->frame = read_sp () - fi->stack_size; + } + return addr; + } + } + /* Now check for the 24bit pc-relative call to __prologue. */ + else if (buf[0] == 0xf4 && buf[1] == 0xe1) + { + CORE_ADDR temp; + status = target_read_memory (addr + 2, buf, 3); + if (status != 0) + { + if (fi && fi->next == NULL && (fi->status & MY_FRAME_IN_SP)) + fi->frame = read_sp (); + return addr; + } + + /* Get the PC this instruction will branch to. */ + temp = (extract_signed_integer (buf, 3) + addr) & 0xffffff; + + /* Get the name of the function at the target address. */ + status = find_pc_partial_function (temp, &name, NULL, NULL); + if (status == 0) + { + if (fi && fi->next == NULL && (fi->status & MY_FRAME_IN_SP)) + fi->frame = read_sp (); + return addr; + } + + /* Note if it is an out of line prologue. */ + out_of_line_prologue = (strcmp (name, "__prologue") == 0); + + /* This sucks up 5 bytes of instruction space. */ + if (out_of_line_prologue) + addr += 5; + + if (addr >= stop) + { + if (fi && fi->next == NULL && (fi->status & MY_FRAME_IN_SP)) + { + fi->stack_size -= 16; + fi->frame = read_sp () - fi->stack_size; + } + return addr; + } + } + + /* Now actually handle the out of line prologue. */ + if (out_of_line_prologue) + { + int outgoing_args_size = 0; + + /* First adjust the stack size for this function. The out of + line prologue saves 4 registers (16bytes of data). */ + if (fi) + fi->stack_size -= 16; + + /* Update fi->frame if necessary. */ + if (fi && fi->next == NULL) + fi->frame = read_sp () - fi->stack_size; + + /* After the out of line prologue, there may be another + stack adjustment for the outgoing arguments. + + Search for add imm8,a3 (0xd3XX) + or add imm16,a3 (0xf70bXXXX) + or add imm24,a3 (0xf467XXXXXX). */ + + status = target_read_memory (addr, buf, 2); + if (status != 0) + { + if (fi) + { + fi->fsr.regs[2] = fi->frame + fi->stack_size + 4; + fi->fsr.regs[3] = fi->frame + fi->stack_size + 8; + fi->fsr.regs[5] = fi->frame + fi->stack_size + 12; + fi->fsr.regs[6] = fi->frame + fi->stack_size + 16; + } + return addr; + } + + if (buf[0] == 0xd3) + { + outgoing_args_size = extract_signed_integer (&buf[1], 1); + addr += 2; + } + else if (buf[0] == 0xf7 && buf[1] == 0x0b) + { + status = target_read_memory (addr + 2, buf, 2); + if (status != 0) + { + if (fi) + { + fi->fsr.regs[2] = fi->frame + fi->stack_size + 4; + fi->fsr.regs[3] = fi->frame + fi->stack_size + 8; + fi->fsr.regs[5] = fi->frame + fi->stack_size + 12; + fi->fsr.regs[6] = fi->frame + fi->stack_size + 16; + } + return addr; + } + outgoing_args_size = extract_signed_integer (buf, 2); + addr += 4; + } + else if (buf[0] == 0xf4 && buf[1] == 0x67) + { + status = target_read_memory (addr + 2, buf, 3); + if (status != 0) + { + if (fi && fi->next == NULL) + { + fi->fsr.regs[2] = fi->frame + fi->stack_size + 4; + fi->fsr.regs[3] = fi->frame + fi->stack_size + 8; + fi->fsr.regs[5] = fi->frame + fi->stack_size + 12; + fi->fsr.regs[6] = fi->frame + fi->stack_size + 16; + } + return addr; + } + outgoing_args_size = extract_signed_integer (buf, 3); + addr += 5; + } + else + outgoing_args_size = 0; + + /* Now that we know the size of the outgoing arguments, fix + fi->frame again if this is the innermost frame. */ + if (fi && fi->next == NULL) + fi->frame -= outgoing_args_size; + + /* Note the register save information and update the stack + size for this frame too. */ + if (fi) + { + fi->fsr.regs[2] = fi->frame + fi->stack_size + 4; + fi->fsr.regs[3] = fi->frame + fi->stack_size + 8; + fi->fsr.regs[5] = fi->frame + fi->stack_size + 12; + fi->fsr.regs[6] = fi->frame + fi->stack_size + 16; + fi->stack_size += outgoing_args_size; + } + /* There can be no more prologue insns, so return now. */ return addr; } -- 2.7.4