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| author | Jeff Law <law@redhat.com> | 2014-06-30 08:08:50 -0600 |
|---|---|---|
| committer | Jeff Law <law@gcc.gnu.org> | 2014-06-30 08:08:50 -0600 |
| commit | 4f82fed2f6dcef2719103a5fd885f6baf9714ce0 (patch) | |
| tree | 7d30196f8f6b6532d8b2f5d5c29c5fa282e12b31 /gcc/tree-ssa-threadedge.c | |
| parent | 6a7253a4a9d6087827414eeee7036d9eb4b1e472 (diff) | |
| download | gcc-4f82fed2f6dcef2719103a5fd885f6baf9714ce0.zip gcc-4f82fed2f6dcef2719103a5fd885f6baf9714ce0.tar.gz gcc-4f82fed2f6dcef2719103a5fd885f6baf9714ce0.tar.bz2 | |
tree-ssa-threadedge.c (simplify_control_stmt_condition): Look deeper into the SSA_NAME_VALUE chain.
tree-optimization/61607
* tree-ssa-threadedge.c (simplify_control_stmt_condition): Look
deeper into the SSA_NAME_VALUE chain.
tree-optimization/61607
* gcc.dg/tree-ssa/pr61607.c: New test.
From-SVN: r212149
Diffstat (limited to 'gcc/tree-ssa-threadedge.c')
| -rw-r--r-- | gcc/tree-ssa-threadedge.c | 37 |
1 files changed, 27 insertions, 10 deletions
diff --git a/gcc/tree-ssa-threadedge.c b/gcc/tree-ssa-threadedge.c index a76a7ce..9807b42 100644 --- a/gcc/tree-ssa-threadedge.c +++ b/gcc/tree-ssa-threadedge.c @@ -542,16 +542,26 @@ simplify_control_stmt_condition (edge e, /* Get the current value of both operands. */ if (TREE_CODE (op0) == SSA_NAME) { - tree tmp = SSA_NAME_VALUE (op0); - if (tmp) - op0 = tmp; + for (int i = 0; i < 2; i++) + { + if (TREE_CODE (op0) == SSA_NAME + && SSA_NAME_VALUE (op0)) + op0 = SSA_NAME_VALUE (op0); + else + break; + } } if (TREE_CODE (op1) == SSA_NAME) { - tree tmp = SSA_NAME_VALUE (op1); - if (tmp) - op1 = tmp; + for (int i = 0; i < 2; i++) + { + if (TREE_CODE (op1) == SSA_NAME + && SSA_NAME_VALUE (op1)) + op1 = SSA_NAME_VALUE (op1); + else + break; + } } if (handle_dominating_asserts) @@ -625,10 +635,17 @@ simplify_control_stmt_condition (edge e, It is possible to get loops in the SSA_NAME_VALUE chains (consider threading the backedge of a loop where we have a loop invariant SSA_NAME used in the condition. */ - if (cached_lhs - && TREE_CODE (cached_lhs) == SSA_NAME - && SSA_NAME_VALUE (cached_lhs)) - cached_lhs = SSA_NAME_VALUE (cached_lhs); + if (cached_lhs) + { + for (int i = 0; i < 2; i++) + { + if (TREE_CODE (cached_lhs) == SSA_NAME + && SSA_NAME_VALUE (cached_lhs)) + cached_lhs = SSA_NAME_VALUE (cached_lhs); + else + break; + } + } /* If we're dominated by a suitable ASSERT_EXPR, then update CACHED_LHS appropriately. */ |