diff options
| -rw-r--r-- | llvm/test/Transforms/InstCombine/cast.ll | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/llvm/test/Transforms/InstCombine/cast.ll b/llvm/test/Transforms/InstCombine/cast.ll index 4621d33d438..0a1f73e7dec 100644 --- a/llvm/test/Transforms/InstCombine/cast.ll +++ b/llvm/test/Transforms/InstCombine/cast.ll @@ -1432,3 +1432,41 @@ define <2 x i32> @test90() { %tmp6 = bitcast <4 x half> <half undef, half undef, half undef, half 0xH3C00> to <2 x i32> ret <2 x i32> %tmp6 } + +; Do not optimize to ashr i64 (shift by 48 > 96 - 64) +define i64 @test91(i64 %A) { +; CHECK-LABEL: @test91( +; CHECK-NEXT: [[C:%.*]] = ashr i64 %A, 48 +; CHECK-NEXT: ret i64 [[C]] +; + %B = sext i64 %A to i96 + %C = lshr i96 %B, 48 + %D = trunc i96 %C to i64 + ret i64 %D +} + +; Do optimize to ashr i64 (shift by 32 <= 96 - 64) +define i64 @test92(i64 %A) { +; CHECK-LABEL: @test92( +; CHECK-NEXT: [[C:%.*]] = ashr i64 %A, 32 +; CHECK-NEXT: ret i64 [[C]] +; + %B = sext i64 %A to i96 + %C = lshr i96 %B, 32 + %D = trunc i96 %C to i64 + ret i64 %D +} + +; When optimizing to ashr i32, don't shift by more than 31. +define i32 @test93(i32 %A) { +; CHECK-LABEL: @test93( +; CHECK-NEXT: [[B:%.*]] = sext i32 %A to i96 +; CHECK-NEXT: [[C:%.*]] = lshr i96 [[B]], 64 +; CHECK-NEXT: [[D:%.*]] = trunc i96 [[C]] to i32 +; CHECK-NEXT: ret i32 [[D]] +; + %B = sext i32 %A to i96 + %C = lshr i96 %B, 64 + %D = trunc i96 %C to i32 + ret i32 %D +} |
