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[PATCH] Fix PR45948: Handle COND_EXPR in expression_expensive_p.
- From: Sebastian Pop <sebpop at gmail dot com>
- To: gcc-patches at gcc dot gnu dot org
- Cc: rguenther at suse dot de, Sebastian Pop <sebpop at gmail dot com>
- Date: Thu, 2 Dec 2010 13:15:15 -0600
- Subject: [PATCH] Fix PR45948: Handle COND_EXPR in expression_expensive_p.
Hi,
this patch makes SCEV const propagation handle COND_EXPRs: previously
they were considered expensive to generate, and now we look at its
operands to decide if it is expensive.
I am testing this on amd64-linux. Ok for trunk after test?
Thanks,
Sebastian
2010-12-02 Sebastian Pop <sebastian.pop@amd.com>
PR middle-end/45948
* tree-scalar-evolution.c (expression_expensive_p): Handle COND_EXPR.
* gcc.dg/tree-ssa/ldist-pr45948.c: New.
---
gcc/ChangeLog | 5 +++++
gcc/testsuite/ChangeLog | 5 +++++
gcc/testsuite/gcc.dg/tree-ssa/ldist-pr45948.c | 23 +++++++++++++++++++++++
gcc/tree-scalar-evolution.c | 6 ++++++
4 files changed, 39 insertions(+), 0 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/ldist-pr45948.c
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index da56fb6..7502bc5 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,10 @@
2010-12-02 Sebastian Pop <sebastian.pop@amd.com>
+ PR middle-end/45948
+ * tree-scalar-evolution.c (expression_expensive_p): Handle COND_EXPR.
+
+2010-12-02 Sebastian Pop <sebastian.pop@amd.com>
+
PR middle-end/45297
* tree-scalar-evolution.c (interpret_rhs_expr): Handle ADDR_EXPR
with MEM_REFs as POINTER_PLUS_EXPR.
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 3eeee83..43b1ae5 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,10 @@
2010-12-02 Sebastian Pop <sebastian.pop@amd.com>
+ PR middle-end/45948
+ * gcc.dg/tree-ssa/ldist-pr45948.c: New.
+
+2010-12-02 Sebastian Pop <sebastian.pop@amd.com>
+
PR tree-optimization/45199
* gcc.dg/tree-ssa/ldist-15.c: New.
* gcc.dg/tree-ssa/ldist-16.c: New.
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ldist-pr45948.c b/gcc/testsuite/gcc.dg/tree-ssa/ldist-pr45948.c
new file mode 100644
index 0000000..f0d07cc
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/ldist-pr45948.c
@@ -0,0 +1,23 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -ftree-loop-distribution -fdump-tree-ldist-details" } */
+
+extern void bar(int);
+
+void
+foo (int i, int n)
+{
+ int a[30];
+ int b[30];
+ for (; i < n; i++)
+ a[i] = b[i] = 0;
+
+ while (1)
+ if (b[0])
+ bar (a[i - 1]);
+}
+
+/* We should apply loop distribution and generate 2 memset (0). */
+
+/* { dg-final { scan-tree-dump "distributed: split to 2" "ldist" } } */
+/* { dg-final { scan-tree-dump-times "__builtin_memset" 4 "ldist" } } */
+/* { dg-final { cleanup-tree-dump "ldist" } } */
diff --git a/gcc/tree-scalar-evolution.c b/gcc/tree-scalar-evolution.c
index 4a4bda9..ab21092 100644
--- a/gcc/tree-scalar-evolution.c
+++ b/gcc/tree-scalar-evolution.c
@@ -3253,6 +3253,12 @@ expression_expensive_p (tree expr)
return false;
code = TREE_CODE (expr);
+
+ if (code == COND_EXPR)
+ return expression_expensive_p (TREE_OPERAND (expr, 0))
+ || expression_expensive_p (TREE_OPERAND (expr, 1))
+ || expression_expensive_p (TREE_OPERAND (expr, 2));
+
if (code == TRUNC_DIV_EXPR
|| code == CEIL_DIV_EXPR
|| code == FLOOR_DIV_EXPR
--
1.7.1