OpenE2K/gcc
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

alpha.c (alpha_expand_prologue): If stack checking is enabled, probe up to frame_size + STACK_CHECK_PROTECT bytes.

Browse Source 
* config/alpha/alpha.c (alpha_expand_prologue): If stack checking
	is enabled, probe up to frame_size + STACK_CHECK_PROTECT bytes.

From-SVN: r164298
This commit is contained in:
Eric Botcazou 2010-09-15 07:24:54 +00:00 committed by Eric Botcazou
parent 6c175675c0
commit 1093719080
2 changed files with 29 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
gcc/ChangeLog
View File

@ -1,3 +1,8 @@
2010-09-15 Eric Botcazou <ebotcazou@adacore.com>
* config/alpha/alpha.c (alpha_expand_prologue): If stack checking
is enabled, probe up to frame_size + STACK_CHECK_PROTECT bytes.
2010-09-15 Olivier Hainque <hainque@adacore.com>
Jose Ruiz <ruiz@adacore.com>

35
gcc/config/alpha/alpha.c
View File

@ -7814,6 +7814,9 @@ alpha_expand_prologue (void)
HOST_WIDE_INT sa_size;
/* Complete stack size needed. */
HOST_WIDE_INT frame_size;
/* Probed stack size; it additionally includes the size of
the "reserve region" if any. */
HOST_WIDE_INT probed_size;
/* Offset from base reg to register save area. */
HOST_WIDE_INT reg_offset;
rtx sa_reg;
@ -7859,20 +7862,26 @@ alpha_expand_prologue (void)
Note that we are only allowed to adjust sp once in the prologue. */
if (frame_size <= 32768)
probed_size = frame_size;
if (flag_stack_check)
probed_size += STACK_CHECK_PROTECT;
if (probed_size <= 32768)
{
if (frame_size > 4096)
if (probed_size > 4096)
{
int probed;
for (probed = 4096; probed < frame_size; probed += 8192)
for (probed = 4096; probed < probed_size; probed += 8192)
emit_insn (gen_probe_stack (GEN_INT (TARGET_ABI_UNICOSMK
? -probed + 64
: -probed)));
/* We only have to do this probe if we aren't saving registers. */
if (sa_size == 0 && frame_size > probed - 4096)
emit_insn (gen_probe_stack (GEN_INT (-frame_size)));
/* We only have to do this probe if we aren't saving registers or
if we are probing beyond the frame because of -fstack-check. */
if ((sa_size == 0 && probed_size > probed - 4096)
|| flag_stack_check)
emit_insn (gen_probe_stack (GEN_INT (-probed_size)));
}
if (frame_size != 0)
@ -7887,10 +7896,11 @@ alpha_expand_prologue (void)
number of 8192 byte blocks to probe. We then probe each block
in the loop and then set SP to the proper location. If the
amount remaining is > 4096, we have to do one more probe if we
are not saving any registers. */
are not saving any registers or if we are probing beyond the
frame because of -fstack-check. */
HOST_WIDE_INT blocks = (frame_size + 4096) / 8192;
HOST_WIDE_INT leftover = frame_size + 4096 - blocks * 8192;
HOST_WIDE_INT blocks = (probed_size + 4096) / 8192;
HOST_WIDE_INT leftover = probed_size + 4096 - blocks * 8192;
rtx ptr = gen_rtx_REG (DImode, 22);
rtx count = gen_rtx_REG (DImode, 23);
rtx seq;
@ -7903,20 +7913,23 @@ alpha_expand_prologue (void)
late in the compilation, generate the loop as a single insn. */
emit_insn (gen_prologue_stack_probe_loop (count, ptr));
if (leftover > 4096 && sa_size == 0)
if ((leftover > 4096 && sa_size == 0) || flag_stack_check)
{
rtx last = gen_rtx_MEM (DImode, plus_constant (ptr, -leftover));
MEM_VOLATILE_P (last) = 1;
emit_move_insn (last, const0_rtx);
}
if (TARGET_ABI_WINDOWS_NT)
if (TARGET_ABI_WINDOWS_NT || flag_stack_check)
{
/* For NT stack unwind (done by 'reverse execution'), it's
not OK to take the result of a loop, even though the value
is already in ptr, so we reload it via a single operation
and subtract it to sp.
Same if -fstack-check is specified, because the probed stack
size is not equal to the frame size.
Yes, that's correct -- we have to reload the whole constant
into a temporary via ldah+lda then subtract from sp. */