2003-05-15 Jeff Johnston <jjohnstn@redhat.com>

* ia64-tdep.c: Increase max_skip_non_prologue_insns to 40.
        (examine_prologue): Support looking through leaf functions, knowing
        they start with mov r2,r12.  Support skipping over indirect stores
        of the input registers.  Upon hitting a non-nop branch instruction
        or predicated instruction, bail out by setting lim_pc to the current
        pc value in the loop.  At the end, if the lim_pc value is still
        beyond our calculated value and we have trust_limit set,
        use the lim_pc value.
This commit is contained in:
Jeff Johnston 2003-05-15 21:38:37 +00:00
parent e4f7904629
commit 5ea2bd7fc0
2 changed files with 84 additions and 7 deletions

View File

@ -1,3 +1,14 @@
2003-05-15 Jeff Johnston <jjohnstn@redhat.com>
* ia64-tdep.c: Increase max_skip_non_prologue_insns to 40.
(examine_prologue): Support looking through leaf functions, knowing
they start with mov r2,r12. Support skipping over indirect stores
of the input registers. Upon hitting a non-nop branch instruction
or predicated instruction, bail out by setting lim_pc to the current
pc value in the loop. At the end, if the lim_pc value is still
beyond our calculated value and we have trust_limit set,
use the lim_pc value.
2003-05-15 Andrew Cagney <cagney@redhat.com>
* dummy-frame.h (deprecated_find_dummy_frame_regcache): Rename

View File

@ -737,7 +737,7 @@ ia64_frame_saved_pc (struct frame_info *frame)
/* Limit the number of skipped non-prologue instructions since examining
of the prologue is expensive. */
static int max_skip_non_prologue_insns = 10;
static int max_skip_non_prologue_insns = 40;
/* Given PC representing the starting address of a function, and
LIM_PC which is the (sloppy) limit to which to scan when looking
@ -825,10 +825,13 @@ examine_prologue (CORE_ADDR pc, CORE_ADDR lim_pc, struct frame_info *frame)
CORE_ADDR spill_addr = 0;
char instores[8];
char infpstores[8];
char reg_contents[256];
int trust_limit;
int frameless = 0;
memset (instores, 0, sizeof instores);
memset (infpstores, 0, sizeof infpstores);
memset (reg_contents, 0, sizeof reg_contents);
if (frame && !get_frame_saved_regs (frame))
{
@ -843,13 +846,14 @@ examine_prologue (CORE_ADDR pc, CORE_ADDR lim_pc, struct frame_info *frame)
return get_frame_extra_info (frame)->after_prologue;
lim_pc = refine_prologue_limit (pc, lim_pc, &trust_limit);
/* Must start with an alloc instruction */
next_pc = fetch_instruction (pc, &it, &instr);
/* We want to check if we have a recognizable function start before we
look ahead for a prologue. */
if (pc < lim_pc && next_pc
&& it == M && ((instr & 0x1ee0000003fLL) == 0x02c00000000LL))
{
/* alloc */
/* alloc - start of a regular function. */
int sor = (int) ((instr & 0x00078000000LL) >> 27);
int sol = (int) ((instr & 0x00007f00000LL) >> 20);
int sof = (int) ((instr & 0x000000fe000LL) >> 13);
@ -864,9 +868,35 @@ examine_prologue (CORE_ADDR pc, CORE_ADDR lim_pc, struct frame_info *frame)
}
else
{
pc = lim_pc; /* Frameless: We're done early. */
if (trust_limit)
last_prologue_pc = lim_pc;
/* Look for a leaf routine. */
if (pc < lim_pc && next_pc
&& (it == I || it == M)
&& ((instr & 0x1ee00000000LL) == 0x10800000000LL))
{
/* adds rN = imm14, rM (or mov rN, rM when imm14 is 0) */
int imm = (int) ((((instr & 0x01000000000LL) ? -1 : 0) << 13)
| ((instr & 0x001f8000000LL) >> 20)
| ((instr & 0x000000fe000LL) >> 13));
int rM = (int) ((instr & 0x00007f00000LL) >> 20);
int rN = (int) ((instr & 0x00000001fc0LL) >> 6);
int qp = (int) (instr & 0x0000000003fLL);
if (qp == 0 && rN == 2 && imm == 0 && rM == 12 && fp_reg == 0)
{
/* mov r2, r12 - beginning of leaf routine */
fp_reg = rN;
frameless = 1;
last_prologue_pc = next_pc;
}
}
/* If we don't recognize a regular function or leaf routine, we are
done. */
if (!fp_reg)
{
pc = lim_pc;
if (trust_limit)
last_prologue_pc = lim_pc;
}
}
/* Loop, looking for prologue instructions, keeping track of
@ -882,6 +912,8 @@ examine_prologue (CORE_ADDR pc, CORE_ADDR lim_pc, struct frame_info *frame)
{
/* Exit loop upon hitting a non-nop branch instruction
or a predicated instruction. */
if (trust_limit)
lim_pc = pc;
break;
}
else if (it == I && ((instr & 0x1eff8000000LL) == 0x00188000000LL))
@ -941,6 +973,20 @@ examine_prologue (CORE_ADDR pc, CORE_ADDR lim_pc, struct frame_info *frame)
spill_reg = rN;
last_prologue_pc = next_pc;
}
else if (qp == 0 && rM >= 32 && rM < 40 && !instores[rM] &&
rN < 256 && imm == 0)
{
/* mov rN, rM where rM is an input register */
reg_contents[rN] = rM;
last_prologue_pc = next_pc;
}
else if (frameless && qp == 0 && rN == fp_reg && imm == 0 &&
rM == 2)
{
/* mov r12, r2 */
last_prologue_pc = next_pc;
break;
}
}
else if (it == M
&& ( ((instr & 0x1efc0000000LL) == 0x0eec0000000LL)
@ -1006,6 +1052,7 @@ examine_prologue (CORE_ADDR pc, CORE_ADDR lim_pc, struct frame_info *frame)
int rN = (int) ((instr & 0x00007f00000LL) >> 20);
int rM = (int) ((instr & 0x000000fe000LL) >> 13);
int qp = (int) (instr & 0x0000000003fLL);
int indirect = rM < 256 ? reg_contents[rM] : 0;
if (qp == 0 && rN == spill_reg && spill_addr != 0
&& (rM == unat_save_reg || rM == pr_save_reg))
{
@ -1040,6 +1087,13 @@ examine_prologue (CORE_ADDR pc, CORE_ADDR lim_pc, struct frame_info *frame)
instores[rM-32] = 1;
last_prologue_pc = next_pc;
}
else if (qp == 0 && 32 <= indirect && indirect < 40 &&
!instores[indirect-32])
{
/* Allow an indirect store of an input register. */
instores[indirect-32] = 1;
last_prologue_pc = next_pc;
}
}
else if (it == M && ((instr & 0x1ff08000000LL) == 0x08c00000000LL))
{
@ -1054,11 +1108,19 @@ examine_prologue (CORE_ADDR pc, CORE_ADDR lim_pc, struct frame_info *frame)
register is permitted. */
int rM = (int) ((instr & 0x000000fe000LL) >> 13);
int qp = (int) (instr & 0x0000000003fLL);
int indirect = rM < 256 ? reg_contents[rM] : 0;
if (qp == 0 && 32 <= rM && rM < 40 && !instores[rM-32])
{
instores[rM-32] = 1;
last_prologue_pc = next_pc;
}
else if (qp == 0 && 32 <= indirect && indirect < 40 &&
!instores[indirect-32])
{
/* Allow an indirect store of an input register. */
instores[indirect-32] = 1;
last_prologue_pc = next_pc;
}
}
else if (it == M && ((instr & 0x1ff88000000LL) == 0x0cc80000000LL))
{
@ -1147,6 +1209,10 @@ examine_prologue (CORE_ADDR pc, CORE_ADDR lim_pc, struct frame_info *frame)
get_frame_extra_info (frame)->fp_reg = fp_reg;
}
/* Try and trust the lim_pc value whenever possible. */
if (trust_limit && lim_pc >= last_prologue_pc)
return lim_pc;
return last_prologue_pc;
}