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author | Chris Lattner <sabre@nondot.org> | 2003-05-29 20:26:30 +0000 |
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committer | Chris Lattner <sabre@nondot.org> | 2003-05-29 20:26:30 +0000 |
commit | faf4cc2da072a1e90c75c711d3a563bf9726a1e6 (patch) | |
tree | ab7d5381d8feb0d5f54b483d40c74b34bcec5b0e /lib | |
parent | 96191aba7daa7097bc1cd2b06fef164854d0e672 (diff) | |
download | external_llvm-faf4cc2da072a1e90c75c711d3a563bf9726a1e6.zip external_llvm-faf4cc2da072a1e90c75c711d3a563bf9726a1e6.tar.gz external_llvm-faf4cc2da072a1e90c75c711d3a563bf9726a1e6.tar.bz2 |
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@6415 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib')
-rw-r--r-- | lib/Transforms/Scalar/PRE.cpp | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/lib/Transforms/Scalar/PRE.cpp b/lib/Transforms/Scalar/PRE.cpp index 6227a37..3a1239f 100644 --- a/lib/Transforms/Scalar/PRE.cpp +++ b/lib/Transforms/Scalar/PRE.cpp @@ -307,6 +307,17 @@ bool PRE::ProcessExpression(Instruction *Expr) { std::vector<Value*> Values; VN->getEqualNumberNodes(Expr, Values); +#if 0 + // FIXME: This should handle PHI nodes correctly. To do this, we need to + // consider expressions of the following form equivalent to this set of + // expressions: + // + // If an operand is a PHI node, add any occurances of the expression with the + // PHI operand replaced with the PHI node operands. This is only valid if the + // PHI operand occurances exist in blocks post-dominated by the incoming edge + // of the PHI node. +#endif + // We have to be careful to handle expression definitions which dominated by // other expressions. These can be directly eliminated in favor of their // dominating value. Keep track of which blocks contain definitions (the key) |