[llvm] [X86] addcarry.ll - add test coverage for #169691 (PR #169716)

[Simon Pilgrim via llvm-commits]

https://github.com/RKSimon created https://github.com/llvm/llvm-project/pull/169716

None

>From d46570a29203cf84253541be28bc2aa36f59e26a Mon Sep 17 00:00:00 2001
From: Simon Pilgrim <llvm-dev at redking.me.uk>
Date: Wed, 26 Nov 2025 19:43:57 +0000
Subject: [PATCH] [X86] addcarry.ll - add test coverage for #169691

---
 llvm/test/CodeGen/X86/addcarry.ll | 38 +++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/llvm/test/CodeGen/X86/addcarry.ll b/llvm/test/CodeGen/X86/addcarry.ll
index 97894db1188e2..f8a04f8514988 100644
--- a/llvm/test/CodeGen/X86/addcarry.ll
+++ b/llvm/test/CodeGen/X86/addcarry.ll
@@ -1513,3 +1513,41 @@ define i1 @pr84831(i64 %arg) {
   %trunc = trunc i63 %or to i1
   ret i1 %trunc
 }
+
+define void @pr169691(ptr %p0, i64 %implicit, i1 zeroext %carry) {
+; CHECK-LABEL: pr169691:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    movq (%rdi), %rax
+; CHECK-NEXT:    addq %rsi, %rax
+; CHECK-NEXT:    setb %cl
+; CHECK-NEXT:    movl %edx, %edx
+; CHECK-NEXT:    addq %rax, %rdx
+; CHECK-NEXT:    setb %al
+; CHECK-NEXT:    orb %cl, %al
+; CHECK-NEXT:    movq %rdx, (%rdi)
+; CHECK-NEXT:    addq 8(%rdi), %rsi
+; CHECK-NEXT:    movzbl %al, %eax
+; CHECK-NEXT:    addq %rsi, %rax
+; CHECK-NEXT:    movq %rax, 8(%rdi)
+; CHECK-NEXT:    retq
+  %a0 = load i64, ptr %p0, align 8
+  %uaddo0 = call { i64, i1 } @llvm.uadd.with.overflow.i64(i64 %a0, i64 %implicit)
+  %uaddo0.1 = extractvalue { i64, i1 } %uaddo0, 1
+  %uaddo0.0 = extractvalue { i64, i1 } %uaddo0, 0
+  %zextc = zext i1 %carry to i64
+  %uaddo0b = call { i64, i1 } @llvm.uadd.with.overflow.i64(i64 %uaddo0.0, i64 %zextc)
+  %uaddo0b.1 = extractvalue { i64, i1 } %uaddo0b, 1
+  %uaddo0b.0 = extractvalue { i64, i1 } %uaddo0b, 0
+  %carry0 = or i1 %uaddo0.1, %uaddo0b.1
+  store i64 %uaddo0b.0, ptr %p0, align 8
+
+  %p1 = getelementptr inbounds nuw i8, ptr %p0, i64 8
+  %a1 = load i64, ptr %p1, align 8
+  %uaddo1 = call { i64, i1 } @llvm.uadd.with.overflow.i64(i64 %a1, i64 %implicit)
+  %uaddo1.0 = extractvalue { i64, i1 } %uaddo1, 0
+  %zext0 = zext i1 %carry0 to i64
+  %uaddo1b = call { i64, i1 } @llvm.uadd.with.overflow.i64(i64 %uaddo1.0, i64 %zext0)
+  %uaddo1b.0 = extractvalue { i64, i1 } %uaddo1b, 0
+  store i64 %uaddo1b.0, ptr %p1, align 8
+  ret void
+}