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Diffstat (limited to 'test/CodeGen/X86/add-of-carry.ll')
| -rw-r--r-- | test/CodeGen/X86/add-of-carry.ll | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/test/CodeGen/X86/add-of-carry.ll b/test/CodeGen/X86/add-of-carry.ll new file mode 100644 index 0000000..f924ec8 --- /dev/null +++ b/test/CodeGen/X86/add-of-carry.ll @@ -0,0 +1,34 @@ +; RUN: llc < %s -march=x86 | FileCheck %s +; <rdar://problem/8449754> + +define i32 @test1(i32 %sum, i32 %x) nounwind readnone ssp { +entry: +; CHECK: test1: +; CHECK: sbbl %ecx, %ecx +; CHECK-NOT: addl +; CHECK: subl %ecx, %eax + %add4 = add i32 %x, %sum + %cmp = icmp ult i32 %add4, %x + %inc = zext i1 %cmp to i32 + %z.0 = add i32 %add4, %inc + ret i32 %z.0 +} + +; Instcombine transforms test1 into test2: +; CHECK: test2: +; CHECK: movl +; CHECK-NEXT: addl +; CHECK-NEXT: sbbl +; CHECK-NEXT: subl +; CHECK-NEXT: ret +define i32 @test2(i32 %sum, i32 %x) nounwind readnone ssp { +entry: + %uadd = call { i32, i1 } @llvm.uadd.with.overflow.i32(i32 %x, i32 %sum) + %0 = extractvalue { i32, i1 } %uadd, 0 + %cmp = extractvalue { i32, i1 } %uadd, 1 + %inc = zext i1 %cmp to i32 + %z.0 = add i32 %0, %inc + ret i32 %z.0 +} + +declare { i32, i1 } @llvm.uadd.with.overflow.i32(i32, i32) nounwind readnone |
