On Thu, Jan 9, 2025 at 5:35 AM Jeff Law <jeffreya...@gmail.com> wrote:
>
>
>
> On 1/8/25 1:53 PM, H.J. Lu wrote:
> > Skip extension on stack pointer since we can't turn
> >
> > (insn 27 26 139 2 (parallel [
> > (set (reg/f:SI 7 sp)
> > (plus:SI (reg/f:SI 7 sp)
> > (const_int 16 [0x10])))
> > (clobber (reg:CC 17 flags))
> > ]) "x.ii":14:17 discrim 1 283 {*addsi_1}
> > (expr_list:REG_ARGS_SIZE (const_int 0 [0])
> > (nil)))
> > ...
> > (insn 43 125 74 2 (set (reg/f:DI 6 bp [145])
> > (zero_extend:DI (reg/f:SI 7 sp))) "x.ii":15:9 175
> > {*zero_extendsidi2}
> > (nil))
> >
> > into
> >
> > (insn 27 26 155 2 (parallel [
> > (set (reg:DI 6 bp)
> > (zero_extend:DI (plus:SI (reg/f:SI 7 sp)
> > (const_int 16 [0x10]))))
> > (clobber (reg:CC 17 flags))
> > ]) "x.ii":14:17 discrim 1 296 {addsi_1_zext}
> > (expr_list:REG_ARGS_SIZE (const_int 0 [0])
> > (nil)))
> > (insn 155 27 139 2 (set (reg:DI 7 sp)
> > (reg:DI 6 bp)) "x.ii":14:17 discrim 1 -1
> > (nil))
> >
> > without updating stack frame info.
> >
> > gcc/
> >
> > PR rtl-optimization/118266
> > * ree.cc (add_removable_extension): Skip extension on stack
> > pointer.
> >
> > gcc/testsuite/
> >
> > PR rtl-optimization/118266
> > * gcc.target/i386/pr118266.c: New test.
> Presumably there were no other uses of sp?
There are many uses of sp, including sp update, push and pop.
> Rather than special casing sp, it seems to me we should probably do this
> for any fixed register.
>
> OK with that change.
>
This is the patch I am testing. I will commit it after regression
test on x86-64.
Thanks.
--
H.J.
From 62c85645f99e07d942e67b444e11713041941d17 Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.to...@gmail.com>
Date: Wed, 8 Jan 2025 20:50:04 +0800
Subject: [PATCH] ree: Skip extension on fixed register
Skip extension on fixed register since we can't turn
(insn 27 26 139 2 (parallel [
(set (reg/f:SI 7 sp)
(plus:SI (reg/f:SI 7 sp)
(const_int 16 [0x10])))
(clobber (reg:CC 17 flags))
]) "x.ii":14:17 discrim 1 283 {*addsi_1}
(expr_list:REG_ARGS_SIZE (const_int 0 [0])
(nil)))
...
(insn 43 125 74 2 (set (reg/f:DI 6 bp [145])
(zero_extend:DI (reg/f:SI 7 sp))) "x.ii":15:9 175 {*zero_extendsidi2}
(nil))
into
(insn 27 26 155 2 (parallel [
(set (reg:DI 6 bp)
(zero_extend:DI (plus:SI (reg/f:SI 7 sp)
(const_int 16 [0x10]))))
(clobber (reg:CC 17 flags))
]) "x.ii":14:17 discrim 1 296 {addsi_1_zext}
(expr_list:REG_ARGS_SIZE (const_int 0 [0])
(nil)))
(insn 155 27 139 2 (set (reg:DI 7 sp)
(reg:DI 6 bp)) "x.ii":14:17 discrim 1 -1
(nil))
without updating stack frame info.
gcc/
PR rtl-optimization/118266
* ree.cc (add_removable_extension): Skip extension on fixed
register.
gcc/testsuite/
PR rtl-optimization/118266
* gcc.target/i386/pr118266.c: New test.
Signed-off-by: H.J. Lu <hjl.to...@gmail.com>
---
gcc/ree.cc | 12 +++++++++++
gcc/testsuite/gcc.target/i386/pr118266.c | 27 ++++++++++++++++++++++++
2 files changed, 39 insertions(+)
create mode 100644 gcc/testsuite/gcc.target/i386/pr118266.c
diff --git a/gcc/ree.cc b/gcc/ree.cc
index a44e8e5625b..bcce9da44af 100644
--- a/gcc/ree.cc
+++ b/gcc/ree.cc
@@ -1113,6 +1113,18 @@ add_removable_extension (const_rtx expr, rtx_insn *insn,
struct df_link *defs, *def;
ext_cand *cand;
+ if (fixed_regs[REGNO (reg)])
+ {
+ if (dump_file)
+ {
+ fprintf (dump_file, "Cannot eliminate extension:\n");
+ print_rtl_single (dump_file, insn);
+ fprintf (dump_file, " because extension on fixed register"
+ " isn't supported.\n");
+ }
+ return;
+ }
+
/* Zero-extension of an undefined value is partly defined (it's
completely undefined for sign-extension, though). So if there exists
a path from the entry to this zero-extension that leaves this register
diff --git a/gcc/testsuite/gcc.target/i386/pr118266.c b/gcc/testsuite/gcc.target/i386/pr118266.c
new file mode 100644
index 00000000000..4c83cd1a561
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr118266.c
@@ -0,0 +1,27 @@
+/* { dg-do compile { target { ! ia32 } } } */
+/* { dg-require-effective-target maybe_x32 } */
+/* { dg-require-effective-target fopenacc } */
+/* { dg-options "-O2 -mx32 -fopenacc" } */
+
+typedef struct {
+ int a;
+ int b;
+ int c;
+} mystruct;
+int main_j;
+int
+main()
+{
+ mystruct *m = (mystruct *)__builtin_malloc (2*sizeof (mystruct)), *mref = m;
+#pragma acc enter data copyin(m[1])
+ for (int i; i < 9; i++) {
+#pragma acc parallel
+ for (; main_j;)
+ ;
+#pragma acc parallel loop copy(mref->b, m->c)
+ for (main_j = 0; main_j < 4; main_j++)
+ ;
+ }
+#pragma acc data copyout(m[ : 1])
+ __builtin_free(m);
+}
--
2.47.1
