t_inst inst;
unsigned long *gen_mask;
{
- if ((inst & 0xf800) == 0xd000 /* sw reg,n($sp) */
- || (inst & 0xff00) == 0xf900) /* sd reg,n($sp) */
+ if ((inst & 0xf800) == 0xd000) /* sw reg,n($sp) */
{
- int reg = mips16_to_32_reg[(inst & 0xf00) >> 8];
+ int reg = mips16_to_32_reg[(inst & 0x700) >> 8];
+ *gen_mask |= (1 << reg);
+ }
+ else if ((inst & 0xff00) == 0xf900) /* sd reg,n($sp) */
+ {
+ int reg = mips16_to_32_reg[(inst & 0xe0) >> 5];
*gen_mask |= (1 << reg);
}
else if ((inst & 0xff00) == 0x6200 /* sw $ra,n($sp) */
CORE_ADDR start_pc = pc;
CORE_ADDR fence = start_pc - heuristic_fence_post;
int instlen;
+ int seen_adjsp = 0;
if (start_pc == 0) return 0;
}
else if (start_pc & 1)
{
- /* On MIPS16, look for the 'entry' pseudo-op at the start
- of a function. This is only going to work if the program
- was compiled with -mentry. Otherwise, there's no reliable
- way of finding the start of a function. */
- if ((read_memory_integer (start_pc & ~1, 2) & 0xf81f)== 0xe809)
- return start_pc;
+ /* 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' */
+ unsigned short inst = read_memory_integer (start_pc & ~1, 2);
+ 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))
{
return start_pc;
}
-static mips_extra_func_info_t
-heuristic_proc_desc(start_pc, limit_pc, next_frame)
+/* Fetch the immediate value from the current 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 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 & 0x7e00);
+ 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;
- unsigned long r30_frame_size = 0;
- 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;
+ 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 */
- 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!! */
+ PROC_FRAME_OFFSET(&temp_proc_desc) = 0;
- if ((word & 0xFFFF0000) == 0x27bd0000 /* addiu $sp,$sp,-i */
- || (word & 0xFFFF0000) == 0x23bd0000 /* addi $sp,$sp,-i */
- || (word & 0xFFFF0000) == 0x67bd0000) { /* daddiu $sp,$sp,-i */
- if (word & 0x8000)
- frame_size += (-word) & 0xffff;
- 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;
+ for (cur_pc = start_pc; cur_pc < limit_pc; cur_pc += MIPS16_INSTLEN)
+ {
+ char buf[MIPS16_INSTLEN];
+ int status, reg, offset;
+
+ /* 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 the instruction. */
+ status = read_memory_nobpt (cur_pc & ~1, buf, MIPS16_INSTLEN);
+ if (status) memory_error (status, cur_pc);
+ inst = (unsigned short) extract_unsigned_integer (buf, MIPS16_INSTLEN);
+
+ 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($sp) */
+ {
+ offset = mips16_get_imm (prev_inst, inst, 8, 4, 0);
+ reg = mips16_to_32_reg[(inst & 0x700) >> 8];
+ PROC_REG_MASK(&temp_proc_desc) |= (1 << reg);
+ temp_saved_regs.regs[reg] = sp + offset;
+ }
+ else if ((inst & 0xff00) == 0xf900) /* sd reg,n($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);
+ temp_saved_regs.regs[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 << 31);
+ temp_saved_regs.regs[31] = sp + offset;
}
- else if ((word & 0xFFE00000) == 0xafa00000) { /* sw reg,offset($sp) */
- int reg = (word & 0x001F0000) >> 16;
- reg_mask |= 1 << reg;
- temp_saved_regs.regs[reg] = sp + (word & 0xffff);
+ 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 << 31);
+ temp_saved_regs.regs[31] = sp + offset;
}
- else if ((word & 0xFFE00000) == 0xffa00000) { /* 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. */
- int reg = (word & 0x001F0000) >> 16;
- reg_mask |= 1 << reg;
- temp_saved_regs.regs[reg] = sp + (word & 0xffff) + 8 - MIPS_REGSIZE;
+ else if (inst == 0x673d) /* move $s1, $sp */
+ {
+ frame_addr = read_next_frame_reg(next_frame, 30);
+ PROC_FRAME_REG (&temp_proc_desc) = 17;
}
- else if ((word & 0xFFFF0000) == 0x27be0000) { /* addiu $30,$sp,size */
- /* Old gcc frame, r30 is virtual frame pointer. */
- 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) == 0xd900) /* sw reg,offset($s1) */
+ {
+ offset = mips16_get_imm (prev_inst, inst, 5, 4, 0);
+ reg = mips16_to_32_reg[(inst & 0xe0) >> 5];
+ PROC_REG_MASK(&temp_proc_desc) |= 1 << reg;
+ temp_saved_regs.regs[reg] = frame_addr + offset;
+ }
+ else if ((inst & 0xFF00) == 0x7900) /* sd reg,offset($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;
+ temp_saved_regs.regs[reg] = frame_addr + offset;
+ }
+ else if ((inst & 0xf81f) == 0xe809 && (inst & 0x700) != 0x700) /* entry */
+ {
+ int areg_count = (inst >> 8) & 7;
+ int sreg_count = (inst >> 6) & 3;
+
+ /* The entry instruction always subtracts 32 from the SP. */
+ PROC_FRAME_OFFSET(&temp_proc_desc) += 32;
+
+ /* Check if a0-a3 were saved in the caller's argument save area. */
+ for (reg = 4, offset = 32; reg < areg_count+4; reg++, offset += 4)
+ {
+ PROC_REG_MASK(&temp_proc_desc) |= 1 << reg;
+ temp_saved_regs.regs[reg] = sp + offset;
+ }
+
+ /* Check if the ra register was pushed on the stack. */
+ offset = 28;
+ if (inst & 0x20)
+ {
+ PROC_REG_MASK(&temp_proc_desc) |= 1 << 31;
+ temp_saved_regs.regs[31] = sp + offset;
+ offset -= 4;
+ }
+
+ /* Check if the s0 and s1 registers were pushed on the stack. */
+ for (reg = 16; reg < sreg_count+16; reg++, offset -= 4)
+ {
+ PROC_REG_MASK(&temp_proc_desc) |= 1 << reg;
+ temp_saved_regs.regs[reg] = sp + offset;
+ }
+ }
+ }
+}
+
+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;
+ for (cur_pc = start_pc; cur_pc < limit_pc; cur_pc += MIPS_INSTLEN)
+ {
+ char buf[MIPS_INSTLEN];
+ unsigned long inst, high_word, low_word;
+ int status, reg;
+
+ /* Fetch the instruction. */
+ status = (unsigned long) read_memory_nobpt (cur_pc, buf, MIPS_INSTLEN);
+ if (status) memory_error (status, cur_pc);
+ inst = (unsigned long) extract_unsigned_integer (buf, MIPS_INSTLEN);
+
+ /* 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($sp) */
+ {
+ PROC_REG_MASK(&temp_proc_desc) |= 1 << reg;
+ temp_saved_regs.regs[reg] = sp + low_word;
+ }
+ else if ((high_word & 0xFFE0) == 0xffa0) /* sd reg,offset($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;
+ temp_saved_regs.regs[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 (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;
}
}
}
- else if ((word & 0xFFFFFFFB) == 0x03a0f021) { /* mov $30,$sp */
- /* New gcc frame, virtual frame pointer is at r30 + frame_size. */
- if (!has_frame_reg) {
- unsigned alloca_adjust;
- has_frame_reg = 1;
- reg30 = read_next_frame_reg(next_frame, 30);
- r30_frame_size = frame_size;
- alloca_adjust = (unsigned)(reg30 - 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;
+ /* 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;
+ temp_saved_regs.regs[reg] = frame_addr + low_word;
}
}
- if (has_frame_reg) {
- PROC_FRAME_REG(&temp_proc_desc) = 30;
- PROC_FRAME_OFFSET(&temp_proc_desc) = r30_frame_size;
- }
- 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
+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 (start_pc & 1)
+ 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
/* It's a simple argument being passed in a general
register.
If the argument length is smaller than the register size,
- we have to adjust the argument on big endian targets. */
+ we have to adjust the argument on big endian targets.
+ But don't do this adjustment on EABI targets. */
if (TARGET_BYTE_ORDER == BIG_ENDIAN
- && partial_len < MIPS_REGSIZE)
+ && partial_len < MIPS_REGSIZE
+ && !MIPS_EABI)
regval <<= ((MIPS_REGSIZE - partial_len) * TARGET_CHAR_BIT);
write_register (argreg, regval);
argreg++;
{
char buf[MIPS_INSTLEN];
int status;
+ unsigned long high_word;
status = read_memory_nobpt (pc, buf, MIPS_INSTLEN);
if (status)
memory_error (status, pc);
inst = (unsigned long)extract_unsigned_integer (buf, MIPS_INSTLEN);
+ high_word = (inst >> 16) & 0xffff;
#if 0
if (lenient && is_delayed (inst))
continue;
#endif
- if ((inst & 0xffff0000) == 0x27bd0000 /* addiu $sp,$sp,offset */
- || (inst & 0xffff0000) == 0x67bd0000) /* daddiu $sp,$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,$t0 */
else if ((inst & 0xFF9F07FF) == 0x00800021) /* move reg,$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;
projects / binutils-gdb.git / commitdiff