diff options
Diffstat (limited to 'test/CodeGen/AArch64/addsub.ll')
| -rw-r--r-- | test/CodeGen/AArch64/addsub.ll | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/test/CodeGen/AArch64/addsub.ll b/test/CodeGen/AArch64/addsub.ll index 09b9f62..d6350a6 100644 --- a/test/CodeGen/AArch64/addsub.ll +++ b/test/CodeGen/AArch64/addsub.ll @@ -24,6 +24,34 @@ define void @add_small() { ret void } +; Make sure we grab the imm variant when the register operand +; can be implicitly zero-extend. +; We used to generate something horrible like this: +; wA = ldrb +; xB = ldimm 12 +; xC = add xB, wA, uxtb +; whereas this can be achieved with: +; wA = ldrb +; xC = add xA, #12 ; <- xA implicitly zero extend wA. +define void @add_small_imm(i8* %p, i64* %q, i32 %b, i32* %addr) { +; CHECK-LABEL: add_small_imm: +entry: + +; CHECK: ldrb w[[LOAD32:[0-9]+]], [x0] + %t = load i8, i8* %p + %promoted = zext i8 %t to i64 + %zextt = zext i8 %t to i32 + %add = add nuw i32 %zextt, %b + +; CHECK: add [[ADD2:x[0-9]+]], x[[LOAD32]], #12 + %add2 = add nuw i64 %promoted, 12 + store i32 %add, i32* %addr + +; CHECK: str [[ADD2]], [x1] + store i64 %add2, i64* %q + ret void +} + ; Add 12-bit immediates, shifted left by 12 bits define void @add_med() { ; CHECK-LABEL: add_med: |