diff options
| -rw-r--r-- | llvm/test/CodeGen/X86/addcarry.ll | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/llvm/test/CodeGen/X86/addcarry.ll b/llvm/test/CodeGen/X86/addcarry.ll index 956d52c063d..33892ad9f5c 100644 --- a/llvm/test/CodeGen/X86/addcarry.ll +++ b/llvm/test/CodeGen/X86/addcarry.ll @@ -386,3 +386,29 @@ define i128 @addcarry1_not(i128 %n) { %2 = add i128 %1, 1 ret i128 %2 } + +define i128 @addcarry_to_subcarry(i64 %a, i64 %b) { +; CHECK-LABEL: addcarry_to_subcarry: +; CHECK: # %bb.0: +; CHECK-NEXT: notq %rsi +; CHECK-NEXT: xorl %eax, %eax +; CHECK-NEXT: movq %rdi, %rcx +; CHECK-NEXT: addq %rsi, %rcx +; CHECK-NEXT: setb %al +; CHECK-NEXT: addq $1, %rcx +; CHECK-NEXT: adcq %rdi, %rax +; CHECK-NEXT: setb %cl +; CHECK-NEXT: movzbl %cl, %edx +; CHECK-NEXT: addq %rsi, %rax +; CHECK-NEXT: adcq $0, %rdx +; CHECK-NEXT: retq + %notb = xor i64 %b, -1 + %notb128 = zext i64 %notb to i128 + %a128 = zext i64 %a to i128 + %sum1 = add i128 %a128, 1 + %sub1 = add i128 %sum1, %notb128 + %hi = lshr i128 %sub1, 64 + %sum2 = add i128 %hi, %a128 + %sub2 = add i128 %sum2, %notb128 + ret i128 %sub2 +} |
