diff options
Diffstat (limited to 'gdb/mips-tdep.c')
| -rw-r--r-- | gdb/mips-tdep.c | 212 |
1 files changed, 67 insertions, 145 deletions
diff --git a/gdb/mips-tdep.c b/gdb/mips-tdep.c index 2b40fdd..e9dc623 100644 --- a/gdb/mips-tdep.c +++ b/gdb/mips-tdep.c @@ -2060,6 +2060,7 @@ mips_insn32_frame_cache (struct frame_info *next_frame, void **this_cache) if ((*this_cache) != NULL) return (*this_cache); + cache = FRAME_OBSTACK_ZALLOC (struct mips_frame_cache); (*this_cache) = cache; cache->saved_regs = trad_frame_alloc_saved_regs (next_frame); @@ -2073,11 +2074,7 @@ mips_insn32_frame_cache (struct frame_info *next_frame, void **this_cache) if (start_addr == 0) start_addr = heuristic_proc_start (pc); -#ifdef NOT_YET proc_desc = heuristic_proc_desc (start_addr, pc, next_frame, *this_cache); -#else - proc_desc = heuristic_proc_desc (start_addr, pc, next_frame, NULL); -#endif } if (proc_desc == NULL) @@ -2086,117 +2083,6 @@ mips_insn32_frame_cache (struct frame_info *next_frame, void **this_cache) heuristic_proc_desc and set the saved_regs right away. */ return cache; - /* Extract the frame's base. */ - cache->base = (frame_unwind_register_signed (next_frame, NUM_REGS + PROC_FRAME_REG (proc_desc)) - + PROC_FRAME_OFFSET (proc_desc) - PROC_FRAME_ADJUST (proc_desc)); - - kernel_trap = PROC_REG_MASK (proc_desc) & 1; - gen_mask = kernel_trap ? 0xFFFFFFFF : PROC_REG_MASK (proc_desc); - float_mask = kernel_trap ? 0xFFFFFFFF : PROC_FREG_MASK (proc_desc); - - /* 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. */ - if (in_prologue (frame_pc_unwind (next_frame), PROC_LOW_ADDR (proc_desc)) - /* Not sure exactly what kernel_trap means, but if it means the - kernel saves the registers without a prologue doing it, we - better not examine the prologue to see whether registers - have been saved yet. */ - && !kernel_trap) - { - /* We need to figure out whether the registers that the - proc_desc claims are saved have been saved yet. */ - - CORE_ADDR addr; - - /* Bitmasks; set if we have found a save for the register. */ - unsigned long gen_save_found = 0; - unsigned long float_save_found = 0; - - addr = PROC_LOW_ADDR (proc_desc); - - /* Scan through this function's instructions preceding the - current PC, and look for those that save registers. */ - while (addr < frame_pc_unwind (next_frame)) - { - mips32_decode_reg_save (mips32_fetch_instruction (addr), - &gen_save_found, &float_save_found); - addr += MIPS_INSTLEN; - } - gen_mask = gen_save_found; - float_mask = float_save_found; - } - - /* Fill in the offsets for the registers which gen_mask says were - saved. */ - { - CORE_ADDR reg_position = (cache->base - + PROC_REG_OFFSET (proc_desc)); - int ireg; - for (ireg = MIPS_NUMREGS - 1; gen_mask; --ireg, gen_mask <<= 1) - if (gen_mask & 0x80000000) - { - cache->saved_regs[NUM_REGS + ireg].addr = reg_position; - reg_position -= mips_abi_regsize (gdbarch); - } - } - - /* Fill in the offsets for the registers which float_mask says were - saved. */ - { - CORE_ADDR reg_position = (cache->base + PROC_FREG_OFFSET (proc_desc)); - int ireg; - - /* 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) - { - const int regno = - NUM_REGS + mips_regnum (current_gdbarch)->fp0 + ireg; - - if (mips_abi_regsize (gdbarch) == 4 - && TARGET_BYTE_ORDER == BFD_ENDIAN_BIG) - { - /* On a big endian 32 bit ABI, floating point registers - are paired to form doubles such that the most - significant part is in $f[N+1] and the least - significant in $f[N] vis: $f[N+1] ||| $f[N]. The - registers are also spilled as a pair and stored as a - double. - - When little-endian the least significant part is - stored first leading to the memory order $f[N] and - then $f[N+1]. - - Unfortunately, when big-endian the most significant - part of the double is stored first, and the least - significant is stored second. This leads to the - registers being ordered in memory as firt $f[N+1] and - then $f[N]. - - For the big-endian case make certain that the - addresses point at the correct (swapped) locations - $f[N] and $f[N+1] pair (keep in mind that - reg_position is decremented each time through the - loop). */ - if ((ireg & 1)) - cache->saved_regs[regno].addr = - reg_position - mips_abi_regsize (gdbarch); - else - cache->saved_regs[regno].addr = - reg_position + mips_abi_regsize (gdbarch); - } - else - cache->saved_regs[regno].addr = reg_position; - reg_position -= mips_abi_regsize (gdbarch); - } - - cache->saved_regs[NUM_REGS + mips_regnum (current_gdbarch)->pc] - = cache->saved_regs[NUM_REGS + RA_REGNUM]; - } - /* SP_REGNUM, contains the value and not the address. */ trad_frame_set_value (cache->saved_regs, NUM_REGS + MIPS_SP_REGNUM, cache->base); @@ -2373,12 +2259,6 @@ read_next_frame_reg (struct frame_info *fi, int regno) regcache_cooked_read_signed (current_regcache, regno, &val); return val; } - else if ((regno % NUM_REGS) == MIPS_SP_REGNUM) - /* MIPS_SP_REGNUM is special, its value is stored in saved_regs. - In fact, it is so special that it can even only be fetched - using a raw register number! Once this code as been converted - to frame-unwind the problem goes away. */ - return frame_unwind_register_signed (fi, regno % NUM_REGS); else return frame_unwind_register_signed (fi, regno); @@ -2456,7 +2336,7 @@ set_reg_offset (struct mips_frame_cache *this_cache, int regnum, CORE_ADDR offset) { if (this_cache != NULL - && this_cache->saved_regs[regnum].addr == 0) + && this_cache->saved_regs[regnum].addr == -1) { this_cache->saved_regs[regnum + 0 * NUM_REGS].addr = offset; this_cache->saved_regs[regnum + 1 * NUM_REGS].addr = offset; @@ -2755,6 +2635,26 @@ mips16_heuristic_proc_desc (CORE_ADDR start_pc, CORE_ADDR limit_pc, } } +/* Mark all the registers as unset in the saved_regs array + of THIS_CACHE. Do nothing if THIS_CACHE is null. */ + +void +reset_saved_regs (struct mips_frame_cache *this_cache) +{ + if (this_cache == NULL || this_cache->saved_regs == NULL) + return; + + { + const int num_regs = NUM_REGS; + int i; + + for (i = 0; i < num_regs; i++) + { + this_cache->saved_regs[i].addr = -1; + } + } +} + static void mips32_heuristic_proc_desc (CORE_ADDR start_pc, CORE_ADDR limit_pc, CORE_ADDR sp, struct frame_info *next_frame, @@ -2762,9 +2662,12 @@ mips32_heuristic_proc_desc (CORE_ADDR start_pc, CORE_ADDR limit_pc, { CORE_ADDR cur_pc; CORE_ADDR frame_addr = 0; /* Value of $r30. Used by gcc for frame-pointer */ + long frame_offset; + int frame_reg = MIPS_SP_REGNUM; + restart: - PROC_FRAME_OFFSET (&temp_proc_desc) = 0; - PROC_FRAME_ADJUST (&temp_proc_desc) = 0; /* offset of FP from SP */ + + frame_offset = 0; for (cur_pc = start_pc; cur_pc < limit_pc; cur_pc += MIPS_INSTLEN) { unsigned long inst, high_word, low_word; @@ -2783,7 +2686,7 @@ restart: || high_word == 0x67bd) /* daddiu $sp,$sp,-i */ { if (low_word & 0x8000) /* negative stack adjustment? */ - PROC_FRAME_OFFSET (&temp_proc_desc) += 0x10000 - low_word; + frame_offset += 0x10000 - low_word; else /* Exit loop if a positive stack adjustment is found, which usually means that the stack cleanup code in the function @@ -2792,34 +2695,37 @@ restart: } else if ((high_word & 0xFFE0) == 0xafa0) /* sw reg,offset($sp) */ { - PROC_REG_MASK (&temp_proc_desc) |= 1 << reg; set_reg_offset (this_cache, reg, sp + low_word); } else if ((high_word & 0xFFE0) == 0xffa0) /* sd reg,offset($sp) */ { /* Irix 6.2 N32 ABI uses sd instructions for saving $gp and $ra. */ - PROC_REG_MASK (&temp_proc_desc) |= 1 << reg; set_reg_offset (this_cache, reg, sp + low_word); } 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)) + if ((long) low_word != frame_offset) frame_addr = sp + low_word; - else if (PROC_FRAME_REG (&temp_proc_desc) == MIPS_SP_REGNUM) + else if (frame_reg == MIPS_SP_REGNUM) { unsigned alloca_adjust; - PROC_FRAME_REG (&temp_proc_desc) = 30; + + frame_reg = 30; frame_addr = read_next_frame_reg (next_frame, NUM_REGS + 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. - */ + /* 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; + /* Need to reset the status of all registers. Otherwise, + we will hit a guard that prevents the new address + for each register to be recomputed during the second + pass. */ + reset_saved_regs (this_cache); goto restart; } } @@ -2830,29 +2736,45 @@ restart: 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) == MIPS_SP_REGNUM) + if (frame_reg == MIPS_SP_REGNUM) { unsigned alloca_adjust; - PROC_FRAME_REG (&temp_proc_desc) = 30; + + frame_reg = 30; frame_addr = read_next_frame_reg (next_frame, NUM_REGS + 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; - } + { + /* FP > SP + frame_size. This may be because of + an alloca or somethings similar. Fix sp to + "pre-alloca" value, and try again. */ + sp = frame_addr; + /* Need to reset the status of all registers. Otherwise, + we will hit a guard that prevents the new address + for each register to be recomputed during the second + pass. */ + reset_saved_regs (this_cache); + goto restart; + } } } else if ((high_word & 0xFFE0) == 0xafc0) /* sw reg,offset($30) */ { - PROC_REG_MASK (&temp_proc_desc) |= 1 << reg; set_reg_offset (this_cache, reg, frame_addr + low_word); } } + + if (this_cache != NULL) + { + this_cache->base = + (frame_unwind_register_signed (next_frame, NUM_REGS + frame_reg) + + frame_offset); + /* FIXME: brobecker/2004-09-15: We should be able to get rid of + this assignment below, eventually. But it's still needed + for now. */ + this_cache->saved_regs[NUM_REGS + mips_regnum (current_gdbarch)->pc] + = this_cache->saved_regs[NUM_REGS + RA_REGNUM]; + } } static mips_extra_func_info_t |