r356317 - [WebAssembly] Use rethrow intrinsic in the rethrow block
Heejin Ahn via cfe-commits
cfe-commits at lists.llvm.org
Fri Mar 15 22:39:13 PDT 2019
Author: aheejin
Date: Fri Mar 15 22:39:12 2019
New Revision: 356317
URL: http://llvm.org/viewvc/llvm-project?rev=356317&view=rev
Log:
[WebAssembly] Use rethrow intrinsic in the rethrow block
Summary:
Because in wasm we merge all catch clauses into one big catchpad, in
case none of the types in catch handlers matches after we test against
each of them, we should unwind to the next EH enclosing scope. For this,
we should NOT use a call to `__cxa_rethrow` but rather a call to our own
rethrow intrinsic, because what we're trying to do here is just to
transfer the control flow into the next enclosing EH pad (or the
caller). Calls to `__cxa_rethrow` should only be used after a call to
`__cxa_begin_catch`.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, sunfish, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D59353
Modified:
cfe/trunk/include/clang/Basic/BuiltinsWebAssembly.def
cfe/trunk/lib/CodeGen/CGBuiltin.cpp
cfe/trunk/lib/CodeGen/CGException.cpp
cfe/trunk/test/CodeGen/builtins-wasm.c
cfe/trunk/test/CodeGenCXX/wasm-eh.cpp
Modified: cfe/trunk/include/clang/Basic/BuiltinsWebAssembly.def
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/BuiltinsWebAssembly.def?rev=356317&r1=356316&r2=356317&view=diff
==============================================================================
--- cfe/trunk/include/clang/Basic/BuiltinsWebAssembly.def (original)
+++ cfe/trunk/include/clang/Basic/BuiltinsWebAssembly.def Fri Mar 15 22:39:12 2019
@@ -37,7 +37,7 @@ BUILTIN(__builtin_wasm_max_f64, "ddd", "
// Exception handling builtins.
TARGET_BUILTIN(__builtin_wasm_throw, "vUiv*", "r", "exception-handling")
-TARGET_BUILTIN(__builtin_wasm_rethrow, "v", "r", "exception-handling")
+TARGET_BUILTIN(__builtin_wasm_rethrow_in_catch, "v", "r", "exception-handling")
// Atomic wait and notify.
BUILTIN(__builtin_wasm_atomic_wait_i32, "ii*iLLi", "n")
Modified: cfe/trunk/lib/CodeGen/CGBuiltin.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGBuiltin.cpp?rev=356317&r1=356316&r2=356317&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGBuiltin.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGBuiltin.cpp Fri Mar 15 22:39:12 2019
@@ -13513,8 +13513,8 @@ Value *CodeGenFunction::EmitWebAssemblyB
Function *Callee = CGM.getIntrinsic(Intrinsic::wasm_throw);
return Builder.CreateCall(Callee, {Tag, Obj});
}
- case WebAssembly::BI__builtin_wasm_rethrow: {
- Function *Callee = CGM.getIntrinsic(Intrinsic::wasm_rethrow);
+ case WebAssembly::BI__builtin_wasm_rethrow_in_catch: {
+ Function *Callee = CGM.getIntrinsic(Intrinsic::wasm_rethrow_in_catch);
return Builder.CreateCall(Callee);
}
case WebAssembly::BI__builtin_wasm_atomic_wait_i32: {
Modified: cfe/trunk/lib/CodeGen/CGException.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGException.cpp?rev=356317&r1=356316&r2=356317&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGException.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGException.cpp Fri Mar 15 22:39:12 2019
@@ -1259,7 +1259,9 @@ void CodeGenFunction::ExitCXXTryStmt(con
}
assert(RethrowBlock != WasmCatchStartBlock && RethrowBlock->empty());
Builder.SetInsertPoint(RethrowBlock);
- CGM.getCXXABI().emitRethrow(*this, /*isNoReturn=*/true);
+ llvm::Function *RethrowInCatchFn =
+ CGM.getIntrinsic(llvm::Intrinsic::wasm_rethrow_in_catch);
+ EmitNoreturnRuntimeCallOrInvoke(RethrowInCatchFn, {});
}
EmitBlock(ContBB);
Modified: cfe/trunk/test/CodeGen/builtins-wasm.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/builtins-wasm.c?rev=356317&r1=356316&r2=356317&view=diff
==============================================================================
--- cfe/trunk/test/CodeGen/builtins-wasm.c (original)
+++ cfe/trunk/test/CodeGen/builtins-wasm.c Fri Mar 15 22:39:12 2019
@@ -44,10 +44,10 @@ void throw(unsigned int tag, void *obj)
// WEBASSEMBLY64: call void @llvm.wasm.throw(i32 %{{.*}}, i8* %{{.*}})
}
-void rethrow(void) {
- return __builtin_wasm_rethrow();
- // WEBASSEMBLY32: call void @llvm.wasm.rethrow()
- // WEBASSEMBLY64: call void @llvm.wasm.rethrow()
+void rethrow_in_catch(void) {
+ return __builtin_wasm_rethrow_in_catch();
+ // WEBASSEMBLY32: call void @llvm.wasm.rethrow.in.catch()
+ // WEBASSEMBLY64: call void @llvm.wasm.rethrow.in.catch()
}
int atomic_wait_i32(int *addr, int expected, long long timeout) {
Modified: cfe/trunk/test/CodeGenCXX/wasm-eh.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/wasm-eh.cpp?rev=356317&r1=356316&r2=356317&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenCXX/wasm-eh.cpp (original)
+++ cfe/trunk/test/CodeGenCXX/wasm-eh.cpp Fri Mar 15 22:39:12 2019
@@ -62,7 +62,7 @@ void test0() {
// CHECK-NEXT: br label %[[TRY_CONT_BB]]
// CHECK: [[RETHROW_BB]]:
-// CHECK-NEXT: call void @__cxa_rethrow() {{.*}} [ "funclet"(token %[[CATCHPAD]]) ]
+// CHECK-NEXT: call void @llvm.wasm.rethrow.in.catch() {{.*}} [ "funclet"(token %[[CATCHPAD]]) ]
// CHECK-NEXT: unreachable
// Single catch-all
@@ -232,7 +232,7 @@ void test6() {
// CHECK: catchret from %[[CATCHPAD]] to label %{{.*}}
// CHECK: [[RETHROW_BB]]:
-// CHECK-NEXT: invoke void @__cxa_rethrow() {{.*}} [ "funclet"(token %[[CATCHPAD]]) ]
+// CHECK-NEXT: invoke void @llvm.wasm.rethrow.in.catch() {{.*}} [ "funclet"(token %[[CATCHPAD]]) ]
// CHECK-NEXT: to label %[[UNREACHABLE_BB:.*]] unwind label %[[EHCLEANUP_BB1:.*]]
// CHECK: [[EHCLEANUP_BB2]]:
@@ -296,7 +296,7 @@ void test7() {
// CHECK: catchret from %[[CATCHPAD0]] to label
-// CHECK: invoke void @__cxa_rethrow() {{.*}} [ "funclet"(token %[[CATCHPAD0]]) ]
+// CHECK: invoke void @llvm.wasm.rethrow.in.catch() {{.*}} [ "funclet"(token %[[CATCHPAD0]]) ]
// CHECK: %[[CLEANUPPAD1:.*]] = cleanuppad within %[[CATCHPAD0]] []
// CHECK: cleanupret from %[[CLEANUPPAD1]] unwind label
@@ -368,11 +368,11 @@ void test8() {
// CHECK: catchret from %[[CATCHPAD1]] to label
-// CHECK: invoke void @__cxa_rethrow() {{.*}} [ "funclet"(token %[[CATCHPAD1]]) ]
+// CHECK: invoke void @llvm.wasm.rethrow.in.catch() {{.*}} [ "funclet"(token %[[CATCHPAD1]]) ]
// CHECK: catchret from %[[CATCHPAD0]] to label
-// CHECK: call void @__cxa_rethrow() {{.*}} [ "funclet"(token %[[CATCHPAD0]]) ]
+// CHECK: call void @llvm.wasm.rethrow.in.catch() {{.*}} [ "funclet"(token %[[CATCHPAD0]]) ]
// CHECK: unreachable
// CHECK: %[[CLEANUPPAD0:.*]] = cleanuppad within %[[CATCHPAD1]] []
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