[clang] [CIR] Add support for C++ conversion operators (PR #151066)

[via cfe-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-clang

Author: Morris Hafner (mmha)

<details>
<summary>Changes</summary>

This fairly simple addition enables codegen for C++ conversion operators

---
Full diff: https://github.com/llvm/llvm-project/pull/151066.diff


2 Files Affected:

- (modified) clang/lib/CIR/CodeGen/CIRGenModule.cpp (+1) 
- (added) clang/test/CIR/CodeGen/cxx-conversion-operators.cpp (+130) 


``````````diff
diff --git a/clang/lib/CIR/CodeGen/CIRGenModule.cpp b/clang/lib/CIR/CodeGen/CIRGenModule.cpp
index 350270518156e..b1db5eeb70dc9 100644
--- a/clang/lib/CIR/CodeGen/CIRGenModule.cpp
+++ b/clang/lib/CIR/CodeGen/CIRGenModule.cpp
@@ -1235,6 +1235,7 @@ void CIRGenModule::emitTopLevelDecl(Decl *decl) {
              decl->getDeclKindName());
     break;
 
+  case Decl::CXXConversion:
   case Decl::CXXMethod:
   case Decl::Function: {
     auto *fd = cast<FunctionDecl>(decl);
diff --git a/clang/test/CIR/CodeGen/cxx-conversion-operators.cpp b/clang/test/CIR/CodeGen/cxx-conversion-operators.cpp
new file mode 100644
index 0000000000000..f56cb3d8e0205
--- /dev/null
+++ b/clang/test/CIR/CodeGen/cxx-conversion-operators.cpp
@@ -0,0 +1,130 @@
+// RUN: %clang_cc1 -std=c++11 -triple aarch64-none-linux-android21 -fclangir -emit-cir %s -o %t.cir
+// RUN: FileCheck --check-prefix=CIR --input-file=%t.cir %s
+// RUN: %clang_cc1 -std=c++11 -triple aarch64-none-linux-android21 -fclangir -emit-llvm %s -o %t-cir.ll
+// RUN: FileCheck --check-prefix=LLVM --input-file=%t-cir.ll %s
+// RUN: %clang_cc1 -std=c++11 -triple aarch64-none-linux-android21 -emit-llvm %s -o %t.ll
+// RUN: FileCheck --check-prefix=OGCG --input-file=%t.ll %s
+
+struct inline_operator {
+    operator int() const {
+        return 987;
+    }
+
+    int operator+(inline_operator) {
+        return 666;
+    }
+};
+
+struct out_of_line_operator {
+    operator int();
+};
+
+out_of_line_operator::operator int() {
+    return 123;
+}
+
+void test() {
+    int x = 42;
+
+    inline_operator i;
+    x = i;
+
+    out_of_line_operator o;
+    x = o;
+}
+
+// CIR: cir.func dso_local @_ZN20out_of_line_operatorcviEv(%[[THIS_ARG:.+]]: !cir.ptr<!rec_out_of_line_operator>{{.*}}) -> !s32i
+// CIR:   %[[THIS_ALLOCA:.+]] = cir.alloca !cir.ptr<!rec_out_of_line_operator>, !cir.ptr<!cir.ptr<!rec_out_of_line_operator>>, ["this", init]
+// CIR:   %[[RETVAL:.+]] = cir.alloca !s32i, !cir.ptr<!s32i>, ["__retval"]
+// CIR:   cir.store %[[THIS_ARG]], %[[THIS_ALLOCA]] : !cir.ptr<!rec_out_of_line_operator>, !cir.ptr<!cir.ptr<!rec_out_of_line_operator>>
+// CIR:   %[[THIS_LOAD:.+]] = cir.load %[[THIS_ALLOCA]] : !cir.ptr<!cir.ptr<!rec_out_of_line_operator>>, !cir.ptr<!rec_out_of_line_operator>
+// CIR:   %[[CONST_123:.+]] = cir.const #cir.int<123> : !s32i
+// CIR:   cir.store %[[CONST_123]], %[[RETVAL]] : !s32i, !cir.ptr<!s32i>
+// CIR:   %[[RET_LOAD:.+]] = cir.load %[[RETVAL]] : !cir.ptr<!s32i>, !s32i
+// CIR:   cir.return %[[RET_LOAD]] : !s32i
+// CIR: }
+
+// CIR: cir.func comdat linkonce_odr @_ZNK15inline_operatorcviEv(%[[INLINE_THIS_ARG:.+]]: !cir.ptr<!rec_inline_operator>{{.*}}) -> !s32i
+// CIR:   %[[INLINE_THIS_ALLOCA:.+]] = cir.alloca !cir.ptr<!rec_inline_operator>, !cir.ptr<!cir.ptr<!rec_inline_operator>>, ["this", init]
+// CIR:   %[[INLINE_RETVAL:.+]] = cir.alloca !s32i, !cir.ptr<!s32i>, ["__retval"]
+// CIR:   cir.store %[[INLINE_THIS_ARG]], %[[INLINE_THIS_ALLOCA]] : !cir.ptr<!rec_inline_operator>, !cir.ptr<!cir.ptr<!rec_inline_operator>>
+// CIR:   %[[INLINE_THIS_LOAD:.+]] = cir.load %[[INLINE_THIS_ALLOCA]] : !cir.ptr<!cir.ptr<!rec_inline_operator>>, !cir.ptr<!rec_inline_operator>
+// CIR:   %[[CONST_987:.+]] = cir.const #cir.int<987> : !s32i
+// CIR:   cir.store %[[CONST_987]], %[[INLINE_RETVAL]] : !s32i, !cir.ptr<!s32i>
+// CIR:   %[[INLINE_RET_LOAD:.+]] = cir.load %[[INLINE_RETVAL]] : !cir.ptr<!s32i>, !s32i
+// CIR:   cir.return %[[INLINE_RET_LOAD]] : !s32i
+// CIR: }
+
+// CIR: cir.func dso_local @_Z4testv()
+// CIR:   %[[X_ALLOCA:.+]] = cir.alloca !s32i, !cir.ptr<!s32i>, ["x", init]
+// CIR:   %[[I_ALLOCA:.+]] = cir.alloca {{.*}}, {{.*}}, ["i"]
+// CIR:   %[[O_ALLOCA:.+]] = cir.alloca {{.*}}, {{.*}}, ["o"]
+// CIR:   %[[CONST_42:.+]] = cir.const #cir.int<42> : !s32i
+// CIR:   cir.store align(4) %[[CONST_42]], %[[X_ALLOCA]] : !s32i, !cir.ptr<!s32i>
+// CIR:   %[[INLINE_CALL:.+]] = cir.call @_ZNK15inline_operatorcviEv(%[[I_ALLOCA]]) : ({{.*}}) -> !s32i
+// CIR:   cir.store align(4) %[[INLINE_CALL]], %[[X_ALLOCA]] : !s32i, !cir.ptr<!s32i>
+// CIR:   %[[OUTLINE_CALL:.+]] = cir.call @_ZN20out_of_line_operatorcviEv(%[[O_ALLOCA]]) : ({{.*}}) -> !s32i
+// CIR:   cir.store align(4) %[[OUTLINE_CALL]], %[[X_ALLOCA]] : !s32i, !cir.ptr<!s32i>
+// CIR:   cir.return
+// CIR: }
+
+// LLVM: define dso_local i32 @_ZN20out_of_line_operatorcviEv(ptr %[[PARAM0:.+]])
+// LLVM:   %[[THIS_ALLOCA:.+]] = alloca ptr, i64 1
+// LLVM:   %[[RETVAL:.+]] = alloca i32, i64 1
+// LLVM:   store ptr %[[PARAM0]], ptr %[[THIS_ALLOCA]]
+// LLVM:   %[[THIS_LOAD:.+]] = load ptr, ptr %[[THIS_ALLOCA]]
+// LLVM:   store i32 123, ptr %[[RETVAL]]
+// LLVM:   %[[RET_LOAD:.+]] = load i32, ptr %[[RETVAL]]
+// LLVM:   ret i32 %[[RET_LOAD]]
+// LLVM: }
+
+// LLVM: define linkonce_odr i32 @_ZNK15inline_operatorcviEv(ptr %[[INLINE_PARAM0:.+]])
+// LLVM:   %[[INLINE_THIS_ALLOCA:.+]] = alloca ptr, i64 1
+// LLVM:   %[[INLINE_RETVAL:.+]] = alloca i32, i64 1
+// LLVM:   store ptr %[[INLINE_PARAM0]], ptr %[[INLINE_THIS_ALLOCA]]
+// LLVM:   %[[INLINE_THIS_LOAD:.+]] = load ptr, ptr %[[INLINE_THIS_ALLOCA]]
+// LLVM:   store i32 987, ptr %[[INLINE_RETVAL]]
+// LLVM:   %[[INLINE_RET_LOAD:.+]] = load i32, ptr %[[INLINE_RETVAL]]
+// LLVM:   ret i32 %[[INLINE_RET_LOAD]]
+// LLVM: }
+
+// LLVM: define dso_local void @_Z4testv()
+// LLVM:   %[[X_ALLOCA:.+]] = alloca i32, i64 1
+// LLVM:   %[[I_ALLOCA:.+]] = alloca {{.*}}, i64 1
+// LLVM:   %[[O_ALLOCA:.+]] = alloca {{.*}}, i64 1
+// LLVM:   store i32 42, ptr %[[X_ALLOCA]]
+// LLVM:   %[[INLINE_CALL:.+]] = call i32 @_ZNK15inline_operatorcviEv(ptr %[[I_ALLOCA]])
+// LLVM:   store i32 %[[INLINE_CALL]], ptr %[[X_ALLOCA]]
+// LLVM:   %[[OUTLINE_CALL:.+]] = call i32 @_ZN20out_of_line_operatorcviEv(ptr %[[O_ALLOCA]])
+// LLVM:   store i32 %[[OUTLINE_CALL]], ptr %[[X_ALLOCA]]
+// LLVM:   ret void
+// LLVM: }
+
+// OGCG: define dso_local noundef i32 @_ZN20out_of_line_operatorcviEv(ptr {{.*}} %[[THIS_PARAM:.+]])
+// OGCG: entry:
+// OGCG:   %[[THIS_ADDR:.+]] = alloca ptr
+// OGCG:   store ptr %[[THIS_PARAM]], ptr %[[THIS_ADDR]]
+// OGCG:   %[[THIS_LOAD:.+]] = load ptr, ptr %[[THIS_ADDR]]
+// OGCG:   ret i32 123
+// OGCG: }
+
+// OGCG: define dso_local void @_Z4testv()
+// OGCG: entry:
+// OGCG:   %[[X_VAR:.+]] = alloca i32
+// OGCG:   %[[I_VAR:.+]] = alloca {{.*}}
+// OGCG:   %[[O_VAR:.+]] = alloca {{.*}}
+// OGCG:   store i32 42, ptr %[[X_VAR]]
+// OGCG:   %[[INLINE_CALL:.+]] = call noundef i32 @_ZNK15inline_operatorcviEv(ptr {{.*}} %[[I_VAR]])
+// OGCG:   store i32 %[[INLINE_CALL]], ptr %[[X_VAR]]
+// OGCG:   %[[OUTLINE_CALL:.+]] = call noundef i32 @_ZN20out_of_line_operatorcviEv(ptr {{.*}} %[[O_VAR]])
+// OGCG:   store i32 %[[OUTLINE_CALL]], ptr %[[X_VAR]]
+// OGCG:   ret void
+// OGCG: }
+
+// OGCG: define linkonce_odr noundef i32 @_ZNK15inline_operatorcviEv(ptr {{.*}} %[[INLINE_THIS_PARAM:.+]])
+// OGCG: entry:
+// OGCG:   %[[INLINE_THIS_ADDR:.+]] = alloca ptr
+// OGCG:   store ptr %[[INLINE_THIS_PARAM]], ptr %[[INLINE_THIS_ADDR]]
+// OGCG:   %[[INLINE_THIS_LOAD:.+]] = load ptr, ptr %[[INLINE_THIS_ADDR]]
+// OGCG:   ret i32 987
+// OGCG: }

``````````

</details>


https://github.com/llvm/llvm-project/pull/151066