Optimize shift lefts of a constant by a value plus constant into a single shift.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174152 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 20 insertions, 0 deletions

diff --git a/test/Transforms/InstCombine/shift.ll b/test/Transforms/InstCombine/shift.ll
index 41f8aa9ee8..117a9060b4 100644
--- a/test/Transforms/InstCombine/shift.ll
+++ b/test/Transforms/InstCombine/shift.ll
@@ -745,3 +745,23 @@ 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
+}