From 4132afb0d2398ae6d211edc9ffc9d2ec25b7abb2 Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Sun, 2 Apr 2006 05:43:13 +0000 Subject: [PATCH] vector casts of casts are eliminable. Transform this: %tmp = cast <4 x uint> %tmp to <4 x int> ; <<4 x int>> [#uses=1] %tmp = cast <4 x int> %tmp to <4 x float> ; <<4 x float>> [#uses=1] into: %tmp = cast <4 x uint> %tmp to <4 x float> ; <<4 x float>> [#uses=1] git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27355 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/Scalar/InstructionCombining.cpp | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp index 82e70073e83..65548aff045 100644 --- a/lib/Transforms/Scalar/InstructionCombining.cpp +++ b/lib/Transforms/Scalar/InstructionCombining.cpp @@ -4539,6 +4539,10 @@ static bool isEliminableCastOfCast(const Type *SrcTy, const Type *MidTy, SrcTy->getPrimitiveSize() < MidTy->getPrimitiveSize()) return true; + // Packed type conversions don't modify bits. + if (isa(SrcTy) && isa(MidTy) &&isa(DstTy)) + return true; + return false; }