Revert r174152. The shift amount may overflow and in that case this transformation...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174156 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/InstCombine/InstCombineShifts.cpp b/lib/Transforms/InstCombine/InstCombineShifts.cpp
index f9e94f225f2cc9eab12a3592fce1999d27054b99..8cf76e5e8a9f888c1bb557bad8d3ee3c98c6e987 100644 (file)
--- a/lib/Transforms/InstCombine/InstCombineShifts.cpp
+++ b/lib/Transforms/InstCombine/InstCombineShifts.cpp
@@ -709,12 +709,6 @@ Instruction *InstCombiner::visitShl(BinaryOperator &I) {
       match(I.getOperand(1), m_Constant(C2)))
     return BinaryOperator::CreateShl(ConstantExpr::getShl(C1, C2), A);
 
-  // shl (c1 , add(y , c2)) -> (shl (shl(c1, c2)), y)
-  if (match(I.getOperand(0), m_Constant(C1)) &&
-      match(I.getOperand(1), m_Add(m_Value(A), m_Constant(C2)))) {
-    return BinaryOperator::CreateShl(ConstantExpr::getShl(C1, C2), A);
-  }
-
   return 0;
 }
 

diff --git a/test/Transforms/InstCombine/shift.ll b/test/Transforms/InstCombine/shift.ll
index 117a9060b4a586c3993b0c8ff88a5cb79d484009..41f8aa9ee8124ddcc05e3fa3340104369faea608 100644 (file)
--- a/test/Transforms/InstCombine/shift.ll
+++ b/test/Transforms/InstCombine/shift.ll
@@ -745,23 +745,3 @@ define i32 @test62(i32 %x) {
 ; CHECK: @test62
 ; CHECK: ashr exact i32 %x, 3
 }
-
-; CHECK: @test63
-; CHECK: shl <4 x i32> <i32 1, i32 2, i32 4, i32 8>, %B
-define <4 x i32> @test63(i32 %n) {
-entry:
-  %K = insertelement <4 x i32> undef, i32 %n, i32 0
-  %B = shufflevector <4 x i32> %K, <4 x i32> undef, <4 x i32> zeroinitializer
-  %A = add <4 x i32> %B, <i32 0, i32 1, i32 2, i32 3>
-  %T = shl <4 x i32> <i32 1, i32 1, i32 1, i32 1>, %A
-  ret <4 x i32> %T
-}
-
-; CHECK: @test64
-; CHECK: shl i32 524288, %n
-define i32 @test64(i32 %n) {
-entry:
-  %A = add i32 %n, 19
-  %T = shl i32 1 , %A
-  ret i32 %T
-}