From dc5e9510be87caada4b1ab9f5bbb012fc63fd64f Mon Sep 17 00:00:00 2001
From: AmrDeveloper <amr96@programmer.net>
Date: Fri, 20 Jun 2025 19:55:55 +0200
Subject: [PATCH] [CIR] Backport ChooseExpr for Scalar expr

---
 clang/lib/CIR/CodeGen/CIRGenExprScalar.cpp    |  6 +++-
 .../CodeGen/builtin-constant-evaluated.cpp    | 34 +++++++++++++++----
 2 files changed, 33 insertions(+), 7 deletions(-)

diff --git a/clang/lib/CIR/CodeGen/CIRGenExprScalar.cpp b/clang/lib/CIR/CodeGen/CIRGenExprScalar.cpp
index 799d80d66a86..3c28642b077f 100644
--- a/clang/lib/CIR/CodeGen/CIRGenExprScalar.cpp
+++ b/clang/lib/CIR/CodeGen/CIRGenExprScalar.cpp
@@ -772,7 +772,11 @@ class ScalarExprEmitter : public StmtVisitor<ScalarExprEmitter, mlir::Value> {
   mlir::Value VisitBlockExpr(const BlockExpr *E) { llvm_unreachable("NYI"); }
   mlir::Value
   VisitAbstractConditionalOperator(const AbstractConditionalOperator *E);
-  mlir::Value VisitChooseExpr(ChooseExpr *E) { llvm_unreachable("NYI"); }
+
+  mlir::Value VisitChooseExpr(ChooseExpr *E) {
+    return Visit(E->getChosenSubExpr());
+  }
+
   mlir::Value VisitVAArgExpr(VAArgExpr *VE);
   mlir::Value VisitObjCStringLiteral(const ObjCStringLiteral *E) {
     llvm_unreachable("NYI");
diff --git a/clang/test/CIR/CodeGen/builtin-constant-evaluated.cpp b/clang/test/CIR/CodeGen/builtin-constant-evaluated.cpp
index c83a21f6708d..9d4d97994d67 100644
--- a/clang/test/CIR/CodeGen/builtin-constant-evaluated.cpp
+++ b/clang/test/CIR/CodeGen/builtin-constant-evaluated.cpp
@@ -1,12 +1,34 @@
 // RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -fclangir -emit-cir %s -o %t.cir
 // RUN: FileCheck %s --check-prefix=CIR --input-file=%t.cir
 
-auto func() {
+auto func() -> int {
   return __builtin_strcmp("", "");
   // CIR:      cir.func dso_local @_Z4funcv()
-  // CIR-NEXT: %0 = cir.alloca !s32i, !cir.ptr<!s32i>, ["__retval"] {alignment = 4 : i64}
-  // CIR-NEXT: %1 = cir.const #cir.int<0> : !s32i
-  // CIR-NEXT: cir.store %1, %0 : !s32i, !cir.ptr<!s32i>
-  // CIR-NEXT: %2 = cir.load{{.*}} %0 : !cir.ptr<!s32i>, !s32i
-  // CIR-NEXT: cir.return %2 : !s32i
+  // CIR-NEXT: %[[RET_VAL:.*]] = cir.alloca !s32i, !cir.ptr<!s32i>, ["__retval"] {alignment = 4 : i64}
+  // CIR-NEXT: %[[VAL:.*]] = cir.const #cir.int<0> : !s32i
+  // CIR-NEXT: cir.store %[[VAL]], %[[RET_VAL]] : !s32i, !cir.ptr<!s32i>
+  // CIR-NEXT: %[[TMP:.*]] = cir.load{{.*}} %0 : !cir.ptr<!s32i>, !s32i
+  // CIR-NEXT: cir.return %[[TMP]] : !s32i
+}
+
+auto func2() -> int {
+  return __builtin_choose_expr(true, 1, 2);
+
+  // CIR:      cir.func dso_local @_Z5func2v()
+  // CIR-NEXT:   %[[RET_VAL:.*]] = cir.alloca !s32i, !cir.ptr<!s32i>, ["__retval"]
+  // CIR-NEXT:   %[[VAL:.*]] = cir.const #cir.int<1> : !s32i
+  // CIR-NEXT:   cir.store %[[VAL]], %[[RET_VAL]] : !s32i, !cir.ptr<!s32i>
+  // CIR-NEXT:   %[[TMP:.*]] = cir.load %[[RET_VAL]] : !cir.ptr<!s32i>, !s32i
+  // CIR-NEXT:   cir.return %[[TMP]] : !s32i
+}
+
+auto func3() -> int {
+  return __builtin_choose_expr(false, 1, 2);
+
+  // CIR:      cir.func dso_local @_Z5func3v()
+  // CIR-NEXT:   %[[RET_VAL:.*]] = cir.alloca !s32i, !cir.ptr<!s32i>, ["__retval"]
+  // CIR-NEXT:   %[[VAL:.*]] = cir.const #cir.int<2> : !s32i
+  // CIR-NEXT:   cir.store %[[VAL]], %[[RET_VAL]] : !s32i, !cir.ptr<!s32i>
+  // CIR-NEXT:   %[[TMP:.*]] = cir.load %[[RET_VAL]] : !cir.ptr<!s32i>, !s32i
+  // CIR-NEXT:   cir.return %[[TMP]] : !s32i
 }