[clang] [CIR] Implement reference type in init catch param (PR #184442)
Amr Hesham via cfe-commits
cfe-commits at lists.llvm.org
Wed Mar 4 09:54:03 PST 2026
https://github.com/AmrDeveloper updated https://github.com/llvm/llvm-project/pull/184442
>From 9c5e72bc8c52fb7535eed180aeec1066aeb95eb5 Mon Sep 17 00:00:00 2001
From: Amr Hesham <amr96 at programmer.net>
Date: Tue, 3 Mar 2026 21:50:46 +0100
Subject: [PATCH 1/2] [CIR] Implement reference type in init catch param
---
clang/lib/CIR/CodeGen/CIRGenItaniumCXXABI.cpp | 18 +++++-
clang/test/CIR/CodeGen/try-catch-tmp.cpp | 64 +++++++++++++++++++
2 files changed, 81 insertions(+), 1 deletion(-)
diff --git a/clang/lib/CIR/CodeGen/CIRGenItaniumCXXABI.cpp b/clang/lib/CIR/CodeGen/CIRGenItaniumCXXABI.cpp
index f195b9325a41c..b8516f85e5051 100644
--- a/clang/lib/CIR/CodeGen/CIRGenItaniumCXXABI.cpp
+++ b/clang/lib/CIR/CodeGen/CIRGenItaniumCXXABI.cpp
@@ -2385,7 +2385,23 @@ static void initCatchParam(CIRGenFunction &cgf, mlir::Value ehToken,
// If we're catching by reference, we can just cast the object
// pointer to the appropriate pointer.
if (isa<ReferenceType>(catchType)) {
- cgf.cgm.errorNYI(loc, "initCatchParam: ReferenceType");
+ QualType caughtType = cast<ReferenceType>(catchType)->getPointeeType();
+ bool endCatchMightThrow = caughtType->isRecordType();
+
+ mlir::Value adjustedExn =
+ callBeginCatch(cgf, ehToken, cirCatchTy, endCatchMightThrow);
+
+ // We have no way to tell the personality function that we're
+ // catching by reference, so if we're catching a pointer,
+ // __cxa_begin_catch will actually return that pointer by value.
+ if (isa<PointerType>(caughtType)) {
+ cgf.cgm.errorNYI(loc, "initCatchParam: catching a pointer");
+ return;
+ }
+
+ mlir::Value exnCast =
+ cgf.getBuilder().createBitcast(adjustedExn, cirCatchTy);
+ cgf.getBuilder().createStore(cgf.getLoc(loc), exnCast, paramAddr);
return;
}
diff --git a/clang/test/CIR/CodeGen/try-catch-tmp.cpp b/clang/test/CIR/CodeGen/try-catch-tmp.cpp
index f7951e229c06f..df656fdd26441 100644
--- a/clang/test/CIR/CodeGen/try-catch-tmp.cpp
+++ b/clang/test/CIR/CodeGen/try-catch-tmp.cpp
@@ -212,6 +212,70 @@ void call_function_inside_try_catch_with_exception_type() {
// OGCG: %[[EXCEPTION_INFO:.*]] = insertvalue { ptr, i32 } %[[TMP_EXCEPTION_INFO]], i32 %[[TMP_EH_TYPE_ID]], 1
// OGCG: resume { ptr, i32 } %[[EXCEPTION_INFO]]
+void call_function_inside_try_catch_with_ref_exception_type() {
+ try {
+ division();
+ } catch (int &ref) {
+ }
+}
+
+// CIR: cir.func {{.*}} @_Z54call_function_inside_try_catch_with_ref_exception_typev() personality(@__gxx_personality_v0)
+// CIR: cir.scope {
+// CIR: %[[EXCEPTION_ADDR:.*]] = cir.alloca !cir.ptr<!s32i>, !cir.ptr<!cir.ptr<!s32i>>, ["ref", const]
+// CIR: cir.try {
+// CIR: %[[CALL:.*]] = cir.call @_Z8divisionv()
+// CIR: cir.yield
+// CIR: } catch [type #cir.global_view<@_ZTIi> : !cir.ptr<!u8i>] (%{{.*}}: !cir.eh_token {{.*}}) {
+// CIR: %[[CATCH_TOKEN:.*]], %[[EXN_PTR:.*]] = cir.begin_catch %{{.*}} : !cir.eh_token -> (!cir.catch_token, !cir.ptr<!s32i>)
+// CIR: cir.cleanup.scope {
+// CIR: cir.store {{.*}} %[[EXN_PTR]], %[[EXCEPTION_ADDR]] : !cir.ptr<!s32i>, !cir.ptr<!cir.ptr<!s32i>>
+// CIR: cir.yield
+// CIR: } cleanup all {
+// CIR: cir.end_catch %[[CATCH_TOKEN]] : !cir.catch_token
+// CIR: cir.yield
+// CIR: }
+// CIR: cir.yield
+// CIR: } unwind (%{{.*}}: !cir.eh_token {{.*}}) {
+// CIR: cir.resume %{{.*}} : !cir.eh_token
+// CIR: }
+// CIR: }
+
+// OGCG: define {{.*}} void @_Z54call_function_inside_try_catch_with_ref_exception_typev() #0 personality ptr @__gxx_personality_v0
+// OGCG: %[[EXCEPTION_ADDR:.*]] = alloca ptr, align 8
+// OGCG: %[[EH_TYPE_ID_ADDR:.*]] = alloca i32, align 4
+// OGCG: %[[E_ADDR:.*]] = alloca ptr, align 8
+// OGCG: %[[CALL:.*]] = invoke noundef i32 @_Z8divisionv()
+// OGCG: to label %[[INVOKE_NORMAL:.*]] unwind label %[[INVOKE_UNWIND:.*]]
+// OGCG: [[INVOKE_NORMAL]]:
+// OGCG: br label %[[TRY_CONT:.*]]
+// OGCG: [[INVOKE_UNWIND]]:
+// OGCG: %[[LANDING_PAD:.*]] = landingpad { ptr, i32 }
+// OGCG: catch ptr @_ZTIi
+// OGCG: %[[EXCEPTION:.*]] = extractvalue { ptr, i32 } %[[LANDING_PAD]], 0
+// OGCG: store ptr %1, ptr %[[EXCEPTION_ADDR]], align 8
+// OGCG: %[[EH_TYPE_ID:.*]] = extractvalue { ptr, i32 } %[[LANDING_PAD]], 1
+// OGCG: store i32 %[[EH_TYPE_ID]], ptr %[[EH_TYPE_ID_ADDR]], align 4
+// OGCG: br label %[[CATCH_DISPATCH:.*]]
+// OGCG: [[CATCH_DISPATCH]]:
+// OGCG: %[[TMP_EH_TYPE_ID:.*]] = load i32, ptr %[[EH_TYPE_ID_ADDR]], align 4
+// OGCG: %[[EH_TYPE_ID:.*]] = call i32 @llvm.eh.typeid.for.p0(ptr @_ZTIi)
+// OGCG: %[[TYPE_ID_EQ:.*]] = icmp eq i32 %[[TMP_EH_TYPE_ID]], %[[EH_TYPE_ID]]
+// OGCG: br i1 %[[TYPE_ID_EQ]], label %[[CATCH_EXCEPTION:.*]], label %[[EH_RESUME:.*]]
+// OGCG: [[CATCH_EXCEPTION]]:
+// OGCG: %[[TMP_EXCEPTION:.*]] = load ptr, ptr %[[EXCEPTION_ADDR]], align 8
+// OGCG: %[[BEGIN_CATCH:.*]] = call ptr @__cxa_begin_catch(ptr %[[TMP_EXCEPTION]])
+// OGCG: store ptr %[[BEGIN_CATCH]], ptr %[[E_ADDR]], align 8
+// OGCG: call void @__cxa_end_catch()
+// OGCG: br label %[[TRY_CONT]]
+// OGCG: [[TRY_CONT]]:
+// OGCG: ret void
+// OGCG: [[EH_RESUME]]:
+// OGCG: %[[TMP_EXCEPTION:.*]] = load ptr, ptr %[[EXCEPTION_ADDR]], align 8
+// OGCG: %[[TMP_EH_TYPE_ID:.*]] = load i32, ptr %[[EH_TYPE_ID_ADDR]], align 4
+// OGCG: %[[TMP_EXCEPTION_INFO:.*]] = insertvalue { ptr, i32 } poison, ptr %[[TMP_EXCEPTION]], 0
+// OGCG: %[[EXCEPTION_INFO:.*]] = insertvalue { ptr, i32 } %[[TMP_EXCEPTION_INFO]], i32 %[[TMP_EH_TYPE_ID]], 1
+// OGCG: resume { ptr, i32 } %[[EXCEPTION_INFO]]
+
void call_function_inside_try_catch_with_complex_exception_type() {
try {
division();
>From f3f06ada9b2dd9ea38630f99107821566730afb4 Mon Sep 17 00:00:00 2001
From: Amr Hesham <amr96 at programmer.net>
Date: Wed, 4 Mar 2026 18:53:40 +0100
Subject: [PATCH 2/2] Rebase and add LLVM test
---
clang/test/CIR/CodeGen/try-catch-tmp.cpp | 51 ++++++++++++++++++++++++
1 file changed, 51 insertions(+)
diff --git a/clang/test/CIR/CodeGen/try-catch-tmp.cpp b/clang/test/CIR/CodeGen/try-catch-tmp.cpp
index df656fdd26441..17542cded2d7d 100644
--- a/clang/test/CIR/CodeGen/try-catch-tmp.cpp
+++ b/clang/test/CIR/CodeGen/try-catch-tmp.cpp
@@ -240,6 +240,57 @@ void call_function_inside_try_catch_with_ref_exception_type() {
// CIR: }
// CIR: }
+// LLVM: define {{.*}} void @_Z54call_function_inside_try_catch_with_ref_exception_typev() {{.*}} personality ptr @__gxx_personality_v0
+// LLVM: br label %[[TRY_SCOPE:.*]]
+// LLVM: [[TRY_SCOPE]]:
+// LLVM: br label %[[TRY_BEGIN:.*]]
+// LLVM: [[TRY_BEGIN]]:
+// LLVM: invoke i32 @_Z8divisionv()
+// LLVM: to label %[[INVOKE_CONT:.*]] unwind label %[[LANDING_PAD:.*]]
+// LLVM: [[INVOKE_CONT:.*]]:
+// LLVM: br label %[[TRY_CONT:.*]]
+// LLVM: [[LANDING_PAD]]:
+// LLVM: %[[LP:.*]] = landingpad { ptr, i32 }
+// LLVM: catch ptr @_ZTIi
+// LLVM: %[[EXN_OBJ:.*]] = extractvalue { ptr, i32 } %[[LP]], 0
+// LLVM: %[[EH_SELECTOR_VAL:.*]] = extractvalue { ptr, i32 } %[[LP]], 1
+// LLVM: br label %[[CATCH:.*]]
+// LLVM: [[CATCH]]:
+// LLVM: %[[EXN_OBJ_PHI:.*]] = phi ptr [ %[[EXN_OBJ:.*]], %[[LANDING_PAD:.*]] ]
+// LLVM: %[[EH_SELECTOR_PHI:.*]] = phi i32 [ %[[EH_SELECTOR_VAL:.*]], %[[LANDING_PAD:.*]] ]
+// LLVM: br label %[[DISPATCH:.*]]
+// LLVM: [[DISPATCH]]:
+// LLVM: %[[EXN_OBJ_PHI1:.*]] = phi ptr [ %[[EXN_OBJ_PHI:.*]], %[[CATCH:.*]] ]
+// LLVM: %[[EH_SELECTOR_PHI1:.*]] = phi i32 [ %[[EH_SELECTOR_PHI:.*]], %[[CATCH:.*]] ]
+// LLVM: %[[EH_TYPE_ID:.*]] = call i32 @llvm.eh.typeid.for.p0(ptr @_ZTIi)
+// LLVM: %[[TYPE_ID_EQ:.*]] = icmp eq i32 %[[EH_SELECTOR_PHI1]], %[[EH_TYPE_ID]]
+// LLVM: br i1 %[[TYPE_ID_EQ]], label %[[BEGIN_CATCH:.*]], label %[[RESUME:.*]]
+// LLVM: [[BEGIN_CATCH]]:
+// LLVM: %[[EXN_OBJ_PHI2:.*]] = phi ptr [ %[[EXN_OBJ_PHI1:.*]], %[[DISPATCH:.*]] ]
+// LLVM: %[[EH_SELECTOR_PHI2:.*]] = phi i32 [ %[[EH_SELECTOR_PHI1:.*]], %[[DISPATCH:.*]] ]
+// LLVM: %[[TOKEN:.*]] = call ptr @__cxa_begin_catch(ptr %[[EXN_OBJ_PHI2]])
+// LLVM: br label %[[CATCH_BODY:.*]]
+// LLVM: [[CATCH_BODY]]:
+// LLVM: store ptr %[[TOKEN]], ptr %{{.*}}, align 8
+// LLVM: br label %[[END_CATCH:.*]]
+// LLVM: [[END_CATCH]]:
+// LLVM: call void @__cxa_end_catch()
+// LLVM: br label %[[END_DISPATCH:.*]]
+// LLVM: [[END_DISPATCH]]:
+// LLVM: br label %[[END_TRY:.*]]
+// LLVM: [[END_TRY]]:
+// LLVM: br label %[[TRY_CONT:.*]]
+// LLVM: [[RESUME]]:
+// LLVM: %[[EXN_OBJ_PHI3:.*]] = phi ptr [ %[[EXN_OBJ_PHI1:.*]], %[[DISPATCH:.*]] ]
+// LLVM: %[[EH_SELECTOR_PHI3:.*]] = phi i32 [ %[[EH_SELECTOR_PHI1:.*]], %[[DISPATCH:.*]] ]
+// LLVM: %[[TMP_EXCEPTION_INFO:.*]] = insertvalue { ptr, i32 } poison, ptr %[[EXN_OBJ_PHI3]], 0
+// LLVM: %[[EXCEPTION_INFO:.*]] = insertvalue { ptr, i32 } %[[TMP_EXCEPTION_INFO]], i32 %[[EH_SELECTOR_PHI3]], 1
+// LLVM: resume { ptr, i32 } %[[EXCEPTION_INFO]]
+// LLVM: [[TRY_CONT]]:
+// LLVM: br label %[[DONE:.*]]
+// LLVM: [[DONE]]:
+// LLVM: ret void
+
// OGCG: define {{.*}} void @_Z54call_function_inside_try_catch_with_ref_exception_typev() #0 personality ptr @__gxx_personality_v0
// OGCG: %[[EXCEPTION_ADDR:.*]] = alloca ptr, align 8
// OGCG: %[[EH_TYPE_ID_ADDR:.*]] = alloca i32, align 4
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