tree-optimization/109849 - missed code hoisting
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Commit Message
The following fixes code hoisting to properly consider ANTIC_OUT instead
of ANTIC_IN. That's a bit expensive to re-compute but since we no
longer iterate we're doing this only once per BB which should be
acceptable. This avoids missing hoistings to the end of blocks where
something in the block clobbers the hoisted value.
Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed.
PR tree-optimization/109849
* tree-ssa-pre.cc (do_hoist_insertion): Compute ANTIC_OUT
and use that to determine what to hoist.
* gcc.dg/tree-ssa/ssa-hoist-8.c: New testcase.
---
gcc/testsuite/gcc.dg/tree-ssa/ssa-hoist-8.c | 22 ++++++++++
gcc/tree-ssa-pre.cc | 48 ++++++++++++++++++---
2 files changed, 64 insertions(+), 6 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/ssa-hoist-8.c
Comments
Hi Richard,
On Tue, 23 May 2023 at 11:55, Richard Biener via Gcc-patches <
gcc-patches@gcc.gnu.org> wrote:
> The following fixes code hoisting to properly consider ANTIC_OUT instead
> of ANTIC_IN. That's a bit expensive to re-compute but since we no
> longer iterate we're doing this only once per BB which should be
> acceptable. This avoids missing hoistings to the end of blocks where
> something in the block clobbers the hoisted value.
>
> Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed.
>
> PR tree-optimization/109849
> * tree-ssa-pre.cc (do_hoist_insertion): Compute ANTIC_OUT
> and use that to determine what to hoist.
>
> * gcc.dg/tree-ssa/ssa-hoist-8.c: New testcase.
>
This patch causes a regression on aarch64:
gcc.target/aarch64/sve/fmla_2.c: \\tst1d found 3 times
FAIL: gcc.target/aarch64/sve/fmla_2.c scan-assembler-times \\tst1d 2
We used to generate:
mov x6, 0
mov w7, 55
whilelo p7.d, wzr, w7
.p2align 3,,7
.L2:
ld1d z30.d, p7/z, [x5, x6, lsl 3]
ld1d z31.d, p7/z, [x4, x6, lsl 3]
cmpne p6.d, p7/z, z30.d, #0
ld1d z30.d, p7/z, [x3, x6, lsl 3]
ld1d z29.d, p6/z, [x2, x6, lsl 3]
movprfx z28, z30
fmla z28.d, p6/m, z31.d, z29.d
fmla z31.d, p6/m, z30.d, z29.d
st1d z28.d, p7, [x1, x6, lsl 3]
st1d z31.d, p7, [x0, x6, lsl 3]
incd x6
whilelo p7.d, w6, w7
b.any .L2
But now:
mov x6, 0
mov w7, 55
ptrue p4.b, all
whilelo p7.d, wzr, w7
.p2align 3,,7
.L2:
ld1d z30.d, p7/z, [x5, x6, lsl 3]
ld1d z31.d, p7/z, [x4, x6, lsl 3]
cmpne p6.d, p7/z, z30.d, #0
cmpeq p5.d, p7/z, z30.d, #0
ld1d z29.d, p6/z, [x2, x6, lsl 3]
ld1d z28.d, p6/z, [x3, x6, lsl 3]
ld1d z30.d, p5/z, [x3, x6, lsl 3]
movprfx z27, z31
fmla z27.d, p4/m, z29.d, z28.d
movprfx z30.d, p6/m, z28.d
fmla z30.d, p6/m, z31.d, z29.d
st1d z27.d, p6, [x0, x6, lsl 3]
st1d z30.d, p7, [x1, x6, lsl 3]
st1d z31.d, p5, [x0, x6, lsl 3]
incd x6
whilelo p7.d, w6, w7
b.any .L2
Christophe
---
> gcc/testsuite/gcc.dg/tree-ssa/ssa-hoist-8.c | 22 ++++++++++
> gcc/tree-ssa-pre.cc | 48 ++++++++++++++++++---
> 2 files changed, 64 insertions(+), 6 deletions(-)
> create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/ssa-hoist-8.c
>
> diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ssa-hoist-8.c
> b/gcc/testsuite/gcc.dg/tree-ssa/ssa-hoist-8.c
> new file mode 100644
> index 00000000000..66bb48e0dc1
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/tree-ssa/ssa-hoist-8.c
> @@ -0,0 +1,22 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -fdump-tree-pre-stats" } */
> +
> +int mem;
> +void foo ();
> +int bar (int flag)
> +{
> + int res;
> + foo ();
> + /* Hoist the load of mem here even though foo () clobbers it. */
> + if (flag)
> + res = mem;
> + else
> + {
> + res = mem;
> + mem = 2;
> + }
> + return res;
> +}
> +
> +/* { dg-final { scan-tree-dump "HOIST inserted: 1" "pre" } } */
> +/* { dg-final { scan-tree-dump-times " = mem;" 1 "pre" } } */
> diff --git a/gcc/tree-ssa-pre.cc b/gcc/tree-ssa-pre.cc
> index 1f7eea93c16..d56431b4145 100644
> --- a/gcc/tree-ssa-pre.cc
> +++ b/gcc/tree-ssa-pre.cc
> @@ -3622,19 +3622,51 @@ do_hoist_insertion (basic_block block)
> && stmt_ends_bb_p (gsi_stmt (last)))
> return false;
>
> - /* Compute the set of hoistable expressions from ANTIC_IN. First
> compute
> + /* We have multiple successors, compute ANTIC_OUT by taking the
> intersection
> + of all of ANTIC_IN translating through PHI nodes. Note we do not
> have to
> + worry about iteration stability here so just intersect the
> expression sets
> + as well. This is a simplification of what we do in
> compute_antic_aux. */
> + bitmap_set_t ANTIC_OUT = bitmap_set_new ();
> + bool first = true;
> + FOR_EACH_EDGE (e, ei, block->succs)
> + {
> + if (first)
> + {
> + phi_translate_set (ANTIC_OUT, ANTIC_IN (e->dest), e);
> + first = false;
> + }
> + else if (!gimple_seq_empty_p (phi_nodes (e->dest)))
> + {
> + bitmap_set_t tmp = bitmap_set_new ();
> + phi_translate_set (tmp, ANTIC_IN (e->dest), e);
> + bitmap_and_into (&ANTIC_OUT->values, &tmp->values);
> + bitmap_and_into (&ANTIC_OUT->expressions, &tmp->expressions);
> + bitmap_set_free (tmp);
> + }
> + else
> + {
> + bitmap_and_into (&ANTIC_OUT->values, &ANTIC_IN
> (e->dest)->values);
> + bitmap_and_into (&ANTIC_OUT->expressions,
> + &ANTIC_IN (e->dest)->expressions);
> + }
> + }
> +
> + /* Compute the set of hoistable expressions from ANTIC_OUT. First
> compute
> hoistable values. */
> bitmap_set hoistable_set;
>
> - /* A hoistable value must be in ANTIC_IN(block)
> + /* A hoistable value must be in ANTIC_OUT(block)
> but not in AVAIL_OUT(BLOCK). */
> bitmap_initialize (&hoistable_set.values, &grand_bitmap_obstack);
> bitmap_and_compl (&hoistable_set.values,
> - &ANTIC_IN (block)->values, &AVAIL_OUT (block)->values);
> + &ANTIC_OUT->values, &AVAIL_OUT (block)->values);
>
> /* Short-cut for a common case: hoistable_set is empty. */
> if (bitmap_empty_p (&hoistable_set.values))
> - return false;
> + {
> + bitmap_set_free (ANTIC_OUT);
> + return false;
> + }
>
> /* Compute which of the hoistable values is in AVAIL_OUT of
> at least one of the successors of BLOCK. */
> @@ -3652,11 +3684,14 @@ do_hoist_insertion (basic_block block)
>
> /* Short-cut for a common case: availout_in_some is empty. */
> if (bitmap_empty_p (&availout_in_some))
> - return false;
> + {
> + bitmap_set_free (ANTIC_OUT);
> + return false;
> + }
>
> /* Hack hoitable_set in-place so we can use
> sorted_array_from_bitmap_set. */
> bitmap_move (&hoistable_set.values, &availout_in_some);
> - hoistable_set.expressions = ANTIC_IN (block)->expressions;
> + hoistable_set.expressions = ANTIC_OUT->expressions;
>
> /* Now finally construct the topological-ordered expression set. */
> vec<pre_expr> exprs = sorted_array_from_bitmap_set (&hoistable_set);
> @@ -3731,6 +3766,7 @@ do_hoist_insertion (basic_block block)
> }
>
> exprs.release ();
> + bitmap_set_free (ANTIC_OUT);
>
> return new_stuff;
> }
> --
> 2.35.3
>
On Wed, 24 May 2023, Christophe Lyon wrote:
> Hi Richard,
>
> On Tue, 23 May 2023 at 11:55, Richard Biener via Gcc-patches <
> gcc-patches@gcc.gnu.org> wrote:
>
> > The following fixes code hoisting to properly consider ANTIC_OUT instead
> > of ANTIC_IN. That's a bit expensive to re-compute but since we no
> > longer iterate we're doing this only once per BB which should be
> > acceptable. This avoids missing hoistings to the end of blocks where
> > something in the block clobbers the hoisted value.
> >
> > Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed.
> >
> > PR tree-optimization/109849
> > * tree-ssa-pre.cc (do_hoist_insertion): Compute ANTIC_OUT
> > and use that to determine what to hoist.
> >
> > * gcc.dg/tree-ssa/ssa-hoist-8.c: New testcase.
> >
>
> This patch causes a regression on aarch64:
> gcc.target/aarch64/sve/fmla_2.c: \\tst1d found 3 times
> FAIL: gcc.target/aarch64/sve/fmla_2.c scan-assembler-times \\tst1d 2
>
>
> We used to generate:
> mov x6, 0
> mov w7, 55
> whilelo p7.d, wzr, w7
> .p2align 3,,7
> .L2:
> ld1d z30.d, p7/z, [x5, x6, lsl 3]
> ld1d z31.d, p7/z, [x4, x6, lsl 3]
> cmpne p6.d, p7/z, z30.d, #0
> ld1d z30.d, p7/z, [x3, x6, lsl 3]
> ld1d z29.d, p6/z, [x2, x6, lsl 3]
> movprfx z28, z30
> fmla z28.d, p6/m, z31.d, z29.d
> fmla z31.d, p6/m, z30.d, z29.d
> st1d z28.d, p7, [x1, x6, lsl 3]
> st1d z31.d, p7, [x0, x6, lsl 3]
> incd x6
> whilelo p7.d, w6, w7
> b.any .L2
>
>
> But now:
> mov x6, 0
> mov w7, 55
> ptrue p4.b, all
> whilelo p7.d, wzr, w7
> .p2align 3,,7
> .L2:
> ld1d z30.d, p7/z, [x5, x6, lsl 3]
> ld1d z31.d, p7/z, [x4, x6, lsl 3]
> cmpne p6.d, p7/z, z30.d, #0
> cmpeq p5.d, p7/z, z30.d, #0
> ld1d z29.d, p6/z, [x2, x6, lsl 3]
> ld1d z28.d, p6/z, [x3, x6, lsl 3]
> ld1d z30.d, p5/z, [x3, x6, lsl 3]
> movprfx z27, z31
> fmla z27.d, p4/m, z29.d, z28.d
> movprfx z30.d, p6/m, z28.d
> fmla z30.d, p6/m, z31.d, z29.d
> st1d z27.d, p6, [x0, x6, lsl 3]
> st1d z30.d, p7, [x1, x6, lsl 3]
> st1d z31.d, p5, [x0, x6, lsl 3]
> incd x6
> whilelo p7.d, w6, w7
> b.any .L2
Thanks for reporting. I'm testing the following together with
a testcase that's not architecture specific.
Richard.
From 2340df60dd9192b30b02de5b34f9cb7c16806430 Mon Sep 17 00:00:00 2001
From: Richard Biener <rguenther@suse.de>
Date: Wed, 24 May 2023 12:36:28 +0200
Subject: [PATCH] tree-optimization/109849 - fix fallout of PRE hoisting change
To: gcc-patches@gcc.gnu.org
The PR109849 fix made us no longer hoist some memory loads because
of the expression set intersection. We can still avoid to compute
the union by simply taking the first sets expressions and leave
the pruning of expressions with values not suitable for hoisting
to sorted_array_from_bitmap_set.
PR tree-optimization/109849
* tree-ssa-pre.cc (do_hoist_insertion): Do not intersect
expressions but take the first sets.
* gcc.dg/tree-ssa/ssa-hoist-9.c: New testcase.
---
gcc/testsuite/gcc.dg/tree-ssa/ssa-hoist-9.c | 20 ++++++++++++++++++++
gcc/tree-ssa-pre.cc | 12 ++++--------
2 files changed, 24 insertions(+), 8 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/ssa-hoist-9.c
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ssa-hoist-9.c b/gcc/testsuite/gcc.dg/tree-ssa/ssa-hoist-9.c
new file mode 100644
index 00000000000..388f79fd80f
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/ssa-hoist-9.c
@@ -0,0 +1,20 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-pre-stats" } */
+
+int foo (int flag, int * __restrict a, int * __restrict b)
+{
+ int res;
+ if (flag)
+ res = *a + *b;
+ else
+ {
+ res = *a;
+ *a = 1;
+ res += *b;
+ }
+ return res;
+}
+
+/* { dg-final { scan-tree-dump "HOIST inserted: 3" "pre" } } */
+/* { dg-final { scan-tree-dump-times " = \\\*" 2 "pre" } } */
+/* { dg-final { scan-tree-dump-times " = \[^\r\n\]* \\\+ \[^\r\n\]*;" 1 "pre" } } */
diff --git a/gcc/tree-ssa-pre.cc b/gcc/tree-ssa-pre.cc
index b1ceea90a8e..7bbfa5ac43d 100644
--- a/gcc/tree-ssa-pre.cc
+++ b/gcc/tree-ssa-pre.cc
@@ -3625,8 +3625,9 @@ do_hoist_insertion (basic_block block)
/* We have multiple successors, compute ANTIC_OUT by taking the intersection
of all of ANTIC_IN translating through PHI nodes. Note we do not have to
- worry about iteration stability here so just intersect the expression sets
- as well. This is a simplification of what we do in compute_antic_aux. */
+ worry about iteration stability here so just use the expression set
+ from the first set and prune that by sorted_array_from_bitmap_set.
+ This is a simplification of what we do in compute_antic_aux. */
bitmap_set_t ANTIC_OUT = bitmap_set_new ();
bool first = true;
FOR_EACH_EDGE (e, ei, block->succs)
@@ -3641,15 +3642,10 @@ do_hoist_insertion (basic_block block)
bitmap_set_t tmp = bitmap_set_new ();
phi_translate_set (tmp, ANTIC_IN (e->dest), e);
bitmap_and_into (&ANTIC_OUT->values, &tmp->values);
- bitmap_and_into (&ANTIC_OUT->expressions, &tmp->expressions);
bitmap_set_free (tmp);
}
else
- {
- bitmap_and_into (&ANTIC_OUT->values, &ANTIC_IN (e->dest)->values);
- bitmap_and_into (&ANTIC_OUT->expressions,
- &ANTIC_IN (e->dest)->expressions);
- }
+ bitmap_and_into (&ANTIC_OUT->values, &ANTIC_IN (e->dest)->values);
}
/* Compute the set of hoistable expressions from ANTIC_OUT. First compute
On Wed, 24 May 2023 at 12:41, Richard Biener <rguenther@suse.de> wrote:
> On Wed, 24 May 2023, Christophe Lyon wrote:
>
> > Hi Richard,
> >
> > On Tue, 23 May 2023 at 11:55, Richard Biener via Gcc-patches <
> > gcc-patches@gcc.gnu.org> wrote:
> >
> > > The following fixes code hoisting to properly consider ANTIC_OUT
> instead
> > > of ANTIC_IN. That's a bit expensive to re-compute but since we no
> > > longer iterate we're doing this only once per BB which should be
> > > acceptable. This avoids missing hoistings to the end of blocks where
> > > something in the block clobbers the hoisted value.
> > >
> > > Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed.
> > >
> > > PR tree-optimization/109849
> > > * tree-ssa-pre.cc (do_hoist_insertion): Compute ANTIC_OUT
> > > and use that to determine what to hoist.
> > >
> > > * gcc.dg/tree-ssa/ssa-hoist-8.c: New testcase.
> > >
> >
> > This patch causes a regression on aarch64:
> > gcc.target/aarch64/sve/fmla_2.c: \\tst1d found 3 times
> > FAIL: gcc.target/aarch64/sve/fmla_2.c scan-assembler-times \\tst1d 2
> >
> >
> > We used to generate:
> > mov x6, 0
> > mov w7, 55
> > whilelo p7.d, wzr, w7
> > .p2align 3,,7
> > .L2:
> > ld1d z30.d, p7/z, [x5, x6, lsl 3]
> > ld1d z31.d, p7/z, [x4, x6, lsl 3]
> > cmpne p6.d, p7/z, z30.d, #0
> > ld1d z30.d, p7/z, [x3, x6, lsl 3]
> > ld1d z29.d, p6/z, [x2, x6, lsl 3]
> > movprfx z28, z30
> > fmla z28.d, p6/m, z31.d, z29.d
> > fmla z31.d, p6/m, z30.d, z29.d
> > st1d z28.d, p7, [x1, x6, lsl 3]
> > st1d z31.d, p7, [x0, x6, lsl 3]
> > incd x6
> > whilelo p7.d, w6, w7
> > b.any .L2
> >
> >
> > But now:
> > mov x6, 0
> > mov w7, 55
> > ptrue p4.b, all
> > whilelo p7.d, wzr, w7
> > .p2align 3,,7
> > .L2:
> > ld1d z30.d, p7/z, [x5, x6, lsl 3]
> > ld1d z31.d, p7/z, [x4, x6, lsl 3]
> > cmpne p6.d, p7/z, z30.d, #0
> > cmpeq p5.d, p7/z, z30.d, #0
> > ld1d z29.d, p6/z, [x2, x6, lsl 3]
> > ld1d z28.d, p6/z, [x3, x6, lsl 3]
> > ld1d z30.d, p5/z, [x3, x6, lsl 3]
> > movprfx z27, z31
> > fmla z27.d, p4/m, z29.d, z28.d
> > movprfx z30.d, p6/m, z28.d
> > fmla z30.d, p6/m, z31.d, z29.d
> > st1d z27.d, p6, [x0, x6, lsl 3]
> > st1d z30.d, p7, [x1, x6, lsl 3]
> > st1d z31.d, p5, [x0, x6, lsl 3]
> > incd x6
> > whilelo p7.d, w6, w7
> > b.any .L2
>
> Thanks for reporting. I'm testing the following together with
> a testcase that's not architecture specific.
>
> Richard.
>
> From 2340df60dd9192b30b02de5b34f9cb7c16806430 Mon Sep 17 00:00:00 2001
> From: Richard Biener <rguenther@suse.de>
> Date: Wed, 24 May 2023 12:36:28 +0200
> Subject: [PATCH] tree-optimization/109849 - fix fallout of PRE hoisting
> change
> To: gcc-patches@gcc.gnu.org
>
> The PR109849 fix made us no longer hoist some memory loads because
> of the expression set intersection. We can still avoid to compute
> the union by simply taking the first sets expressions and leave
> the pruning of expressions with values not suitable for hoisting
> to sorted_array_from_bitmap_set.
>
> PR tree-optimization/109849
> * tree-ssa-pre.cc (do_hoist_insertion): Do not intersect
> expressions but take the first sets.
>
> * gcc.dg/tree-ssa/ssa-hoist-9.c: New testcase.
>
Thanks, I confirm that this fixes the problem I reported on aarch64.
Christophe
> ---
> gcc/testsuite/gcc.dg/tree-ssa/ssa-hoist-9.c | 20 ++++++++++++++++++++
> gcc/tree-ssa-pre.cc | 12 ++++--------
> 2 files changed, 24 insertions(+), 8 deletions(-)
> create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/ssa-hoist-9.c
>
> diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ssa-hoist-9.c
> b/gcc/testsuite/gcc.dg/tree-ssa/ssa-hoist-9.c
> new file mode 100644
> index 00000000000..388f79fd80f
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/tree-ssa/ssa-hoist-9.c
> @@ -0,0 +1,20 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -fdump-tree-pre-stats" } */
> +
> +int foo (int flag, int * __restrict a, int * __restrict b)
> +{
> + int res;
> + if (flag)
> + res = *a + *b;
> + else
> + {
> + res = *a;
> + *a = 1;
> + res += *b;
> + }
> + return res;
> +}
> +
> +/* { dg-final { scan-tree-dump "HOIST inserted: 3" "pre" } } */
> +/* { dg-final { scan-tree-dump-times " = \\\*" 2 "pre" } } */
> +/* { dg-final { scan-tree-dump-times " = \[^\r\n\]* \\\+ \[^\r\n\]*;" 1
> "pre" } } */
> diff --git a/gcc/tree-ssa-pre.cc b/gcc/tree-ssa-pre.cc
> index b1ceea90a8e..7bbfa5ac43d 100644
> --- a/gcc/tree-ssa-pre.cc
> +++ b/gcc/tree-ssa-pre.cc
> @@ -3625,8 +3625,9 @@ do_hoist_insertion (basic_block block)
>
> /* We have multiple successors, compute ANTIC_OUT by taking the
> intersection
> of all of ANTIC_IN translating through PHI nodes. Note we do not
> have to
> - worry about iteration stability here so just intersect the
> expression sets
> - as well. This is a simplification of what we do in
> compute_antic_aux. */
> + worry about iteration stability here so just use the expression set
> + from the first set and prune that by sorted_array_from_bitmap_set.
> + This is a simplification of what we do in compute_antic_aux. */
> bitmap_set_t ANTIC_OUT = bitmap_set_new ();
> bool first = true;
> FOR_EACH_EDGE (e, ei, block->succs)
> @@ -3641,15 +3642,10 @@ do_hoist_insertion (basic_block block)
> bitmap_set_t tmp = bitmap_set_new ();
> phi_translate_set (tmp, ANTIC_IN (e->dest), e);
> bitmap_and_into (&ANTIC_OUT->values, &tmp->values);
> - bitmap_and_into (&ANTIC_OUT->expressions, &tmp->expressions);
> bitmap_set_free (tmp);
> }
> else
> - {
> - bitmap_and_into (&ANTIC_OUT->values, &ANTIC_IN
> (e->dest)->values);
> - bitmap_and_into (&ANTIC_OUT->expressions,
> - &ANTIC_IN (e->dest)->expressions);
> - }
> + bitmap_and_into (&ANTIC_OUT->values, &ANTIC_IN (e->dest)->values);
> }
>
> /* Compute the set of hoistable expressions from ANTIC_OUT. First
> compute
> --
> 2.35.3
>
>
new file mode 100644
@@ -0,0 +1,22 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-pre-stats" } */
+
+int mem;
+void foo ();
+int bar (int flag)
+{
+ int res;
+ foo ();
+ /* Hoist the load of mem here even though foo () clobbers it. */
+ if (flag)
+ res = mem;
+ else
+ {
+ res = mem;
+ mem = 2;
+ }
+ return res;
+}
+
+/* { dg-final { scan-tree-dump "HOIST inserted: 1" "pre" } } */
+/* { dg-final { scan-tree-dump-times " = mem;" 1 "pre" } } */
@@ -3622,19 +3622,51 @@ do_hoist_insertion (basic_block block)
&& stmt_ends_bb_p (gsi_stmt (last)))
return false;
- /* Compute the set of hoistable expressions from ANTIC_IN. First compute
+ /* We have multiple successors, compute ANTIC_OUT by taking the intersection
+ of all of ANTIC_IN translating through PHI nodes. Note we do not have to
+ worry about iteration stability here so just intersect the expression sets
+ as well. This is a simplification of what we do in compute_antic_aux. */
+ bitmap_set_t ANTIC_OUT = bitmap_set_new ();
+ bool first = true;
+ FOR_EACH_EDGE (e, ei, block->succs)
+ {
+ if (first)
+ {
+ phi_translate_set (ANTIC_OUT, ANTIC_IN (e->dest), e);
+ first = false;
+ }
+ else if (!gimple_seq_empty_p (phi_nodes (e->dest)))
+ {
+ bitmap_set_t tmp = bitmap_set_new ();
+ phi_translate_set (tmp, ANTIC_IN (e->dest), e);
+ bitmap_and_into (&ANTIC_OUT->values, &tmp->values);
+ bitmap_and_into (&ANTIC_OUT->expressions, &tmp->expressions);
+ bitmap_set_free (tmp);
+ }
+ else
+ {
+ bitmap_and_into (&ANTIC_OUT->values, &ANTIC_IN (e->dest)->values);
+ bitmap_and_into (&ANTIC_OUT->expressions,
+ &ANTIC_IN (e->dest)->expressions);
+ }
+ }
+
+ /* Compute the set of hoistable expressions from ANTIC_OUT. First compute
hoistable values. */
bitmap_set hoistable_set;
- /* A hoistable value must be in ANTIC_IN(block)
+ /* A hoistable value must be in ANTIC_OUT(block)
but not in AVAIL_OUT(BLOCK). */
bitmap_initialize (&hoistable_set.values, &grand_bitmap_obstack);
bitmap_and_compl (&hoistable_set.values,
- &ANTIC_IN (block)->values, &AVAIL_OUT (block)->values);
+ &ANTIC_OUT->values, &AVAIL_OUT (block)->values);
/* Short-cut for a common case: hoistable_set is empty. */
if (bitmap_empty_p (&hoistable_set.values))
- return false;
+ {
+ bitmap_set_free (ANTIC_OUT);
+ return false;
+ }
/* Compute which of the hoistable values is in AVAIL_OUT of
at least one of the successors of BLOCK. */
@@ -3652,11 +3684,14 @@ do_hoist_insertion (basic_block block)
/* Short-cut for a common case: availout_in_some is empty. */
if (bitmap_empty_p (&availout_in_some))
- return false;
+ {
+ bitmap_set_free (ANTIC_OUT);
+ return false;
+ }
/* Hack hoitable_set in-place so we can use sorted_array_from_bitmap_set. */
bitmap_move (&hoistable_set.values, &availout_in_some);
- hoistable_set.expressions = ANTIC_IN (block)->expressions;
+ hoistable_set.expressions = ANTIC_OUT->expressions;
/* Now finally construct the topological-ordered expression set. */
vec<pre_expr> exprs = sorted_array_from_bitmap_set (&hoistable_set);
@@ -3731,6 +3766,7 @@ do_hoist_insertion (basic_block block)
}
exprs.release ();
+ bitmap_set_free (ANTIC_OUT);
return new_stuff;
}