diff options
| -rw-r--r-- | llvm/test/Transforms/InstCombine/shuffle_select.ll | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/llvm/test/Transforms/InstCombine/shuffle_select.ll b/llvm/test/Transforms/InstCombine/shuffle_select.ll index 97a1920acc8..10021ea92c3 100644 --- a/llvm/test/Transforms/InstCombine/shuffle_select.ll +++ b/llvm/test/Transforms/InstCombine/shuffle_select.ll @@ -268,6 +268,21 @@ define <4 x i32> @shl_mul(<4 x i32> %v0) { ret <4 x i32> %t3 } +; PR37806 - https://bugs.llvm.org/show_bug.cgi?id=37806 +; Demanded elements + simplification can remove the mul alone, but that's not the best case. + +define <4 x i32> @mul_is_nop_shl(<4 x i32> %v0) { +; CHECK-LABEL: @mul_is_nop_shl( +; CHECK-NEXT: [[T2:%.*]] = shl <4 x i32> [[V0:%.*]], <i32 5, i32 6, i32 7, i32 8> +; CHECK-NEXT: [[T3:%.*]] = shufflevector <4 x i32> [[V0]], <4 x i32> [[T2]], <4 x i32> <i32 0, i32 5, i32 6, i32 7> +; CHECK-NEXT: ret <4 x i32> [[T3]] +; + %t1 = mul <4 x i32> %v0, <i32 1, i32 2, i32 3, i32 4> + %t2 = shl <4 x i32> %v0, <i32 5, i32 6, i32 7, i32 8> + %t3 = shufflevector <4 x i32> %t1, <4 x i32> %t2, <4 x i32> <i32 0, i32 5, i32 6, i32 7> + ret <4 x i32> %t3 +} + define <4 x i32> @shl_mul_not_constant_shift_amount(<4 x i32> %v0) { ; CHECK-LABEL: @shl_mul_not_constant_shift_amount( ; CHECK-NEXT: [[T1:%.*]] = shl <4 x i32> <i32 1, i32 2, i32 3, i32 4>, [[V0:%.*]] |
