From 1951f1016cd8eec62db59a76840bde6a61d53ad4 Mon Sep 17 00:00:00 2001 From: Marc Glisse Date: Wed, 12 Jun 2013 19:56:30 +0200 Subject: [PATCH] re PR tree-optimization/57361 (Remove self memory assignment) 2013-06-12 Marc Glisse PR tree-optimization/57361 gcc/ * tree-ssa-dse.c (dse_possible_dead_store_p): Handle self-assignment. gcc/testsuite/ * gcc.dg/tree-ssa/pr57361.c: New file. From-SVN: r200034 --- gcc/ChangeLog | 5 +++++ gcc/testsuite/ChangeLog | 5 +++++ gcc/testsuite/gcc.dg/tree-ssa/pr57361.c | 9 +++++++++ gcc/tree-ssa-dse.c | 7 +++++++ 4 files changed, 26 insertions(+) create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/pr57361.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 0b154319344..ec3daf24ed6 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2013-06-12 Marc Glisse + + PR tree-optimization/57361 + * tree-ssa-dse.c (dse_possible_dead_store_p): Handle self-assignment. + 2013-06-12 Sofiane Naci * config/aarch64/aarch64-simd.md (aarch64_combine): convert to split. diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 187f2ef0641..dc29124a7ee 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2013-06-12 Marc Glisse + + PR tree-optimization/57361 + * gcc.dg/tree-ssa/pr57361.c: New file. + 2013-06-12 Ramana Radhakrishnan * gcc.target/arm/unaligned-memcpy-4.c (src, dst): Initialize diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr57361.c b/gcc/testsuite/gcc.dg/tree-ssa/pr57361.c new file mode 100644 index 00000000000..81f27b3cd1f --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr57361.c @@ -0,0 +1,9 @@ +/* { dg-do compile } */ +/* { dg-options "-O -fdump-tree-dse1-details" } */ + +struct A { int x; double y; }; +void f (struct A *a) { + *a = *a; +} + +/* { dg-final { scan-tree-dump "Deleted dead store" "dse1"} } */ diff --git a/gcc/tree-ssa-dse.c b/gcc/tree-ssa-dse.c index ad99ea9d5d4..39f47abd83b 100644 --- a/gcc/tree-ssa-dse.c +++ b/gcc/tree-ssa-dse.c @@ -84,6 +84,13 @@ dse_possible_dead_store_p (gimple stmt, gimple *use_stmt) *use_stmt = NULL; + /* Self-assignments are zombies. */ + if (operand_equal_p (gimple_assign_rhs1 (stmt), gimple_assign_lhs (stmt), 0)) + { + *use_stmt = stmt; + return true; + } + /* Find the first dominated statement that clobbers (part of) the memory stmt stores to with no intermediate statement that may use part of the memory stmt stores. That is, find a store that may -- 2.30.2