[WebAssembly] Make llvm.wasm.throw invokable #128104
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`llvm.wasm.throw` intrinsic can throw but it was not invokable. Not sure what the rationale was when it was first written that way, but I think at least in Emscripten's C++ exception support with the Wasm port of libunwind, `__builtin_wasm_throw`, which is lowered down to `llvm.wasm.rethrow`, is used only within `_Unwind_RaiseException`, which is a one-liner and thus does not need an `invoke`: https://github.com/emscripten-core/emscripten/blob/720e97f76d6f19e0c6a2d6988988cfe23f0517fb/system/lib/libunwind/src/Unwind-wasm.c#L69 (`_Unwind_RaiseException` is called by `__cxa_throw`, which is generated by the `throw` C++ keyword) But this does not address other direct uses of the builtin in C++, whose use I'm not sure about but is not prohibited. Also other language frontends may need to use the builtin in different functions, which has `try`-`catch`es or destructors. This makes `llvm.wasm.throw` invokable in the backend. To do that, this adds a custom lowering routine to `SelectionDAGBuilder::visitInvoke`, like we did for `llvm.wasm.rethrow`. This does not generate `invoke`s for `__builtin_wasm_throw` yet, which will be done by a follow-up PR. Addresses llvm#124710.
llvmbot
added
backend:WebAssembly
llvm:SelectionDAG
|
@llvm/pr-subscribers-backend-webassembly Author: Heejin Ahn (aheejin) Changes
But this does not address other direct uses of the builtin in C++, whose use I'm not sure about but is not prohibited. Also other language frontends may need to use the builtin in different functions, which has This makes This does not generate Addresses #124710. Full diff: https://github.com/llvm/llvm-project/pull/128104.diff 4 Files Affected:
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 1c58a7f05446c..2b333bd81a570 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -3360,10 +3360,23 @@ void SelectionDAGBuilder::visitInvoke(const InvokeInst &I) {
case Intrinsic::experimental_gc_statepoint:
LowerStatepoint(cast<GCStatepointInst>(I), EHPadBB);
break;
+ // wasm_throw, wasm_rethrow: This is usually done in visitTargetIntrinsic,
+ // but this intrinsic is special because it can be invoked, so we manually
+ // lower it to a DAG node here.
+ case Intrinsic::wasm_throw: {
+ SmallVector<SDValue, 8> Ops;
+ Ops.push_back(getControlRoot()); // inchain for the terminator node
+ const TargetLowering &TLI = DAG.getTargetLoweringInfo();
+ Ops.push_back(
+ DAG.getTargetConstant(Intrinsic::wasm_throw, getCurSDLoc(),
+ TLI.getPointerTy(DAG.getDataLayout())));
+ Ops.push_back(getValue(I.getArgOperand(0))); // tag
+ Ops.push_back(getValue(I.getArgOperand(1))); // thrown value
+ SDVTList VTs = DAG.getVTList(ArrayRef<EVT>({MVT::Other})); // outchain
+ DAG.setRoot(DAG.getNode(ISD::INTRINSIC_VOID, getCurSDLoc(), VTs, Ops));
+ break;
+ }
case Intrinsic::wasm_rethrow: {
- // This is usually done in visitTargetIntrinsic, but this intrinsic is
- // special because it can be invoked, so we manually lower it to a DAG
- // node here.
SmallVector<SDValue, 8> Ops;
Ops.push_back(getControlRoot()); // inchain for the terminator node
const TargetLowering &TLI = DAG.getTargetLoweringInfo();
diff --git a/llvm/lib/CodeGen/WasmEHPrepare.cpp b/llvm/lib/CodeGen/WasmEHPrepare.cpp
index d18196b2217f5..fc98f594660bb 100644
--- a/llvm/lib/CodeGen/WasmEHPrepare.cpp
+++ b/llvm/lib/CodeGen/WasmEHPrepare.cpp
@@ -201,10 +201,8 @@ bool WasmEHPrepareImpl::prepareThrows(Function &F) {
// delete all following instructions within the BB, and delete all the dead
// children of the BB as well.
for (User *U : ThrowF->users()) {
- // A call to @llvm.wasm.throw() is only generated from __cxa_throw()
- // builtin call within libcxxabi, and cannot be an InvokeInst.
- auto *ThrowI = cast<CallInst>(U);
- if (ThrowI->getFunction() != &F)
+ auto *ThrowI = dyn_cast<CallInst>(U);
+ if (!ThrowI || ThrowI->getFunction() != &F)
continue;
Changed = true;
auto *BB = ThrowI->getParent();
diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index 8432779c107de..0ef4438450ea2 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -5203,10 +5203,12 @@ void Verifier::visitInstruction(Instruction &I) {
F->getIntrinsicID() == Intrinsic::experimental_patchpoint ||
F->getIntrinsicID() == Intrinsic::fake_use ||
F->getIntrinsicID() == Intrinsic::experimental_gc_statepoint ||
+ F->getIntrinsicID() == Intrinsic::wasm_throw ||
F->getIntrinsicID() == Intrinsic::wasm_rethrow ||
IsAttachedCallOperand(F, CBI, i),
"Cannot invoke an intrinsic other than donothing, patchpoint, "
- "statepoint, coro_resume, coro_destroy or clang.arc.attachedcall",
+ "statepoint, coro_resume, coro_destroy, clang.arc.attachedcall or "
+ "wasm.(re)throw",
&I);
Check(F->getParent() == &M, "Referencing function in another module!", &I,
&M, F, F->getParent());
diff --git a/llvm/test/CodeGen/WebAssembly/exception.ll b/llvm/test/CodeGen/WebAssembly/exception.ll
index febab822a6a9e..57d1f37c0039f 100644
--- a/llvm/test/CodeGen/WebAssembly/exception.ll
+++ b/llvm/test/CodeGen/WebAssembly/exception.ll
@@ -566,6 +566,32 @@ unreachable: ; preds = %entry
unreachable
}
+; This tests whether llvm.wasm.throw intrinsic can invoked and iseled correctly.
+
+; CHECK-LABEL: invoke_throw:
+; CHECK: try_table (catch __cpp_exception 0)
+; CHECK: local.get 0
+; CHECK: throw __cpp_exception
+; CHECK: end_try_table
+define void @invoke_throw(ptr %p) personality ptr @__gxx_wasm_personality_v0 {
+entry:
+ invoke void @llvm.wasm.throw(i32 0, ptr %p)
+ to label %try.cont unwind label %catch.dispatch
+
+catch.dispatch: ; preds = %entry
+ %0 = catchswitch within none [label %catch.start] unwind to caller
+
+catch.start: ; preds = %catch.dispatch
+ %1 = catchpad within %0 [ptr null]
+ %2 = call ptr @llvm.wasm.get.exception(token %1)
+ %3 = call i32 @llvm.wasm.get.ehselector(token %1)
+ %4 = call ptr @__cxa_begin_catch(ptr %2) #4 [ "funclet"(token %1) ]
+ call void @__cxa_end_catch() [ "funclet"(token %1) ]
+ catchret from %1 to label %try.cont
+
+try.cont: ; preds = %catch, %entry
+ ret void
+}
declare void @foo()
declare void @bar(ptr)
|
|
@llvm/pr-subscribers-llvm-ir Author: Heejin Ahn (aheejin) Changes
But this does not address other direct uses of the builtin in C++, whose use I'm not sure about but is not prohibited. Also other language frontends may need to use the builtin in different functions, which has This makes This does not generate Addresses #124710. Full diff: https://github.com/llvm/llvm-project/pull/128104.diff 4 Files Affected:
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 1c58a7f05446c..2b333bd81a570 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -3360,10 +3360,23 @@ void SelectionDAGBuilder::visitInvoke(const InvokeInst &I) {
case Intrinsic::experimental_gc_statepoint:
LowerStatepoint(cast<GCStatepointInst>(I), EHPadBB);
break;
+ // wasm_throw, wasm_rethrow: This is usually done in visitTargetIntrinsic,
+ // but this intrinsic is special because it can be invoked, so we manually
+ // lower it to a DAG node here.
+ case Intrinsic::wasm_throw: {
+ SmallVector<SDValue, 8> Ops;
+ Ops.push_back(getControlRoot()); // inchain for the terminator node
+ const TargetLowering &TLI = DAG.getTargetLoweringInfo();
+ Ops.push_back(
+ DAG.getTargetConstant(Intrinsic::wasm_throw, getCurSDLoc(),
+ TLI.getPointerTy(DAG.getDataLayout())));
+ Ops.push_back(getValue(I.getArgOperand(0))); // tag
+ Ops.push_back(getValue(I.getArgOperand(1))); // thrown value
+ SDVTList VTs = DAG.getVTList(ArrayRef<EVT>({MVT::Other})); // outchain
+ DAG.setRoot(DAG.getNode(ISD::INTRINSIC_VOID, getCurSDLoc(), VTs, Ops));
+ break;
+ }
case Intrinsic::wasm_rethrow: {
- // This is usually done in visitTargetIntrinsic, but this intrinsic is
- // special because it can be invoked, so we manually lower it to a DAG
- // node here.
SmallVector<SDValue, 8> Ops;
Ops.push_back(getControlRoot()); // inchain for the terminator node
const TargetLowering &TLI = DAG.getTargetLoweringInfo();
diff --git a/llvm/lib/CodeGen/WasmEHPrepare.cpp b/llvm/lib/CodeGen/WasmEHPrepare.cpp
index d18196b2217f5..fc98f594660bb 100644
--- a/llvm/lib/CodeGen/WasmEHPrepare.cpp
+++ b/llvm/lib/CodeGen/WasmEHPrepare.cpp
@@ -201,10 +201,8 @@ bool WasmEHPrepareImpl::prepareThrows(Function &F) {
// delete all following instructions within the BB, and delete all the dead
// children of the BB as well.
for (User *U : ThrowF->users()) {
- // A call to @llvm.wasm.throw() is only generated from __cxa_throw()
- // builtin call within libcxxabi, and cannot be an InvokeInst.
- auto *ThrowI = cast<CallInst>(U);
- if (ThrowI->getFunction() != &F)
+ auto *ThrowI = dyn_cast<CallInst>(U);
+ if (!ThrowI || ThrowI->getFunction() != &F)
continue;
Changed = true;
auto *BB = ThrowI->getParent();
diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index 8432779c107de..0ef4438450ea2 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -5203,10 +5203,12 @@ void Verifier::visitInstruction(Instruction &I) {
F->getIntrinsicID() == Intrinsic::experimental_patchpoint ||
F->getIntrinsicID() == Intrinsic::fake_use ||
F->getIntrinsicID() == Intrinsic::experimental_gc_statepoint ||
+ F->getIntrinsicID() == Intrinsic::wasm_throw ||
F->getIntrinsicID() == Intrinsic::wasm_rethrow ||
IsAttachedCallOperand(F, CBI, i),
"Cannot invoke an intrinsic other than donothing, patchpoint, "
- "statepoint, coro_resume, coro_destroy or clang.arc.attachedcall",
+ "statepoint, coro_resume, coro_destroy, clang.arc.attachedcall or "
+ "wasm.(re)throw",
&I);
Check(F->getParent() == &M, "Referencing function in another module!", &I,
&M, F, F->getParent());
diff --git a/llvm/test/CodeGen/WebAssembly/exception.ll b/llvm/test/CodeGen/WebAssembly/exception.ll
index febab822a6a9e..57d1f37c0039f 100644
--- a/llvm/test/CodeGen/WebAssembly/exception.ll
+++ b/llvm/test/CodeGen/WebAssembly/exception.ll
@@ -566,6 +566,32 @@ unreachable: ; preds = %entry
unreachable
}
+; This tests whether llvm.wasm.throw intrinsic can invoked and iseled correctly.
+
+; CHECK-LABEL: invoke_throw:
+; CHECK: try_table (catch __cpp_exception 0)
+; CHECK: local.get 0
+; CHECK: throw __cpp_exception
+; CHECK: end_try_table
+define void @invoke_throw(ptr %p) personality ptr @__gxx_wasm_personality_v0 {
+entry:
+ invoke void @llvm.wasm.throw(i32 0, ptr %p)
+ to label %try.cont unwind label %catch.dispatch
+
+catch.dispatch: ; preds = %entry
+ %0 = catchswitch within none [label %catch.start] unwind to caller
+
+catch.start: ; preds = %catch.dispatch
+ %1 = catchpad within %0 [ptr null]
+ %2 = call ptr @llvm.wasm.get.exception(token %1)
+ %3 = call i32 @llvm.wasm.get.ehselector(token %1)
+ %4 = call ptr @__cxa_begin_catch(ptr %2) #4 [ "funclet"(token %1) ]
+ call void @__cxa_end_catch() [ "funclet"(token %1) ]
+ catchret from %1 to label %try.cont
+
+try.cont: ; preds = %catch, %entry
+ ret void
+}
declare void @foo()
declare void @bar(ptr)
|
|
@llvm/pr-subscribers-llvm-selectiondag Author: Heejin Ahn (aheejin) Changes
But this does not address other direct uses of the builtin in C++, whose use I'm not sure about but is not prohibited. Also other language frontends may need to use the builtin in different functions, which has This makes This does not generate Addresses #124710. Full diff: https://github.com/llvm/llvm-project/pull/128104.diff 4 Files Affected:
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 1c58a7f05446c..2b333bd81a570 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -3360,10 +3360,23 @@ void SelectionDAGBuilder::visitInvoke(const InvokeInst &I) {
case Intrinsic::experimental_gc_statepoint:
LowerStatepoint(cast<GCStatepointInst>(I), EHPadBB);
break;
+ // wasm_throw, wasm_rethrow: This is usually done in visitTargetIntrinsic,
+ // but this intrinsic is special because it can be invoked, so we manually
+ // lower it to a DAG node here.
+ case Intrinsic::wasm_throw: {
+ SmallVector<SDValue, 8> Ops;
+ Ops.push_back(getControlRoot()); // inchain for the terminator node
+ const TargetLowering &TLI = DAG.getTargetLoweringInfo();
+ Ops.push_back(
+ DAG.getTargetConstant(Intrinsic::wasm_throw, getCurSDLoc(),
+ TLI.getPointerTy(DAG.getDataLayout())));
+ Ops.push_back(getValue(I.getArgOperand(0))); // tag
+ Ops.push_back(getValue(I.getArgOperand(1))); // thrown value
+ SDVTList VTs = DAG.getVTList(ArrayRef<EVT>({MVT::Other})); // outchain
+ DAG.setRoot(DAG.getNode(ISD::INTRINSIC_VOID, getCurSDLoc(), VTs, Ops));
+ break;
+ }
case Intrinsic::wasm_rethrow: {
- // This is usually done in visitTargetIntrinsic, but this intrinsic is
- // special because it can be invoked, so we manually lower it to a DAG
- // node here.
SmallVector<SDValue, 8> Ops;
Ops.push_back(getControlRoot()); // inchain for the terminator node
const TargetLowering &TLI = DAG.getTargetLoweringInfo();
diff --git a/llvm/lib/CodeGen/WasmEHPrepare.cpp b/llvm/lib/CodeGen/WasmEHPrepare.cpp
index d18196b2217f5..fc98f594660bb 100644
--- a/llvm/lib/CodeGen/WasmEHPrepare.cpp
+++ b/llvm/lib/CodeGen/WasmEHPrepare.cpp
@@ -201,10 +201,8 @@ bool WasmEHPrepareImpl::prepareThrows(Function &F) {
// delete all following instructions within the BB, and delete all the dead
// children of the BB as well.
for (User *U : ThrowF->users()) {
- // A call to @llvm.wasm.throw() is only generated from __cxa_throw()
- // builtin call within libcxxabi, and cannot be an InvokeInst.
- auto *ThrowI = cast<CallInst>(U);
- if (ThrowI->getFunction() != &F)
+ auto *ThrowI = dyn_cast<CallInst>(U);
+ if (!ThrowI || ThrowI->getFunction() != &F)
continue;
Changed = true;
auto *BB = ThrowI->getParent();
diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index 8432779c107de..0ef4438450ea2 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -5203,10 +5203,12 @@ void Verifier::visitInstruction(Instruction &I) {
F->getIntrinsicID() == Intrinsic::experimental_patchpoint ||
F->getIntrinsicID() == Intrinsic::fake_use ||
F->getIntrinsicID() == Intrinsic::experimental_gc_statepoint ||
+ F->getIntrinsicID() == Intrinsic::wasm_throw ||
F->getIntrinsicID() == Intrinsic::wasm_rethrow ||
IsAttachedCallOperand(F, CBI, i),
"Cannot invoke an intrinsic other than donothing, patchpoint, "
- "statepoint, coro_resume, coro_destroy or clang.arc.attachedcall",
+ "statepoint, coro_resume, coro_destroy, clang.arc.attachedcall or "
+ "wasm.(re)throw",
&I);
Check(F->getParent() == &M, "Referencing function in another module!", &I,
&M, F, F->getParent());
diff --git a/llvm/test/CodeGen/WebAssembly/exception.ll b/llvm/test/CodeGen/WebAssembly/exception.ll
index febab822a6a9e..57d1f37c0039f 100644
--- a/llvm/test/CodeGen/WebAssembly/exception.ll
+++ b/llvm/test/CodeGen/WebAssembly/exception.ll
@@ -566,6 +566,32 @@ unreachable: ; preds = %entry
unreachable
}
+; This tests whether llvm.wasm.throw intrinsic can invoked and iseled correctly.
+
+; CHECK-LABEL: invoke_throw:
+; CHECK: try_table (catch __cpp_exception 0)
+; CHECK: local.get 0
+; CHECK: throw __cpp_exception
+; CHECK: end_try_table
+define void @invoke_throw(ptr %p) personality ptr @__gxx_wasm_personality_v0 {
+entry:
+ invoke void @llvm.wasm.throw(i32 0, ptr %p)
+ to label %try.cont unwind label %catch.dispatch
+
+catch.dispatch: ; preds = %entry
+ %0 = catchswitch within none [label %catch.start] unwind to caller
+
+catch.start: ; preds = %catch.dispatch
+ %1 = catchpad within %0 [ptr null]
+ %2 = call ptr @llvm.wasm.get.exception(token %1)
+ %3 = call i32 @llvm.wasm.get.ehselector(token %1)
+ %4 = call ptr @__cxa_begin_catch(ptr %2) #4 [ "funclet"(token %1) ]
+ call void @__cxa_end_catch() [ "funclet"(token %1) ]
+ catchret from %1 to label %try.cont
+
+try.cont: ; preds = %catch, %entry
+ ret void
+}
declare void @foo()
declare void @bar(ptr)
|
aheejin
added a commit
to aheejin/llvm-project
that referenced
this pull request
Feb 21, 2025
Even though `__builtin_wasm_throw`, which is lowered down to
`llvm.wasm.throw`, throws,
```cpp
try {
__builtin_wasm_throw(0, obj);
} catch (...) {
}
```
does not generate `invoke`. This is because we have assumed the
intrinsic cannot be invoked, which doesn't make much sense. (See llvm#128104
for the historical context)
llvm#128104 made `llvm.wasm.throw` intrinsic invokable in the backend. This
actually generates `invoke`s in Clang for `__builtin_wasm_throw`.
While we're at it, this also generates `invoke`s for
`__builtin_wasm_rethrow`, which is actually not used anywhere in C++
support. I haven't deleted it just in case in may have uses later. (For
example, to support rethrow functionality that carries stack trace
with exnref)
Depends on llvm#128104 for the CI to pass.
Fixes llvm#124710.
|
✅ With the latest revision this PR passed the C/C++ code formatter. |
arsenm
reviewed
Feb 21, 2025
Comment on lines
3367
to
3374
| SmallVector<SDValue, 8> Ops; | ||
| Ops.push_back(getControlRoot()); // inchain for the terminator node | ||
| const TargetLowering &TLI = DAG.getTargetLoweringInfo(); | ||
| Ops.push_back( | ||
| DAG.getTargetConstant(Intrinsic::wasm_throw, getCurSDLoc(), | ||
| TLI.getPointerTy(DAG.getDataLayout()))); | ||
| Ops.push_back(getValue(I.getArgOperand(0))); // tag | ||
| Ops.push_back(getValue(I.getArgOperand(1))); // thrown value |
There was a problem hiding this comment.
Can replace opts with a static sized, initialized array
arsenm
reviewed
Feb 21, 2025
| const TargetLowering &TLI = DAG.getTargetLoweringInfo(); | ||
| Ops.push_back( | ||
| SmallVector<SDValue, 8> Ops = { |
aheejin
commented
Feb 21, 2025
Comment on lines
+3381
to
+3384
| std::array<SDValue, 2> Ops = { | ||
| getControlRoot(), // inchain for the terminator node | ||
| DAG.getTargetConstant(Intrinsic::wasm_rethrow, getCurSDLoc(), | ||
| TLI.getPointerTy(DAG.getDataLayout()))); | ||
| TLI.getPointerTy(DAG.getDataLayout()))}; |
There was a problem hiding this comment.
This just makes the existing wasm_rethrow use std::array and NFC
dschuff
approved these changes
Feb 24, 2025
aheejin
added a commit
that referenced
this pull request
Feb 25, 2025
Even though `__builtin_wasm_throw`, which is lowered down to
`llvm.wasm.throw`, throws,
```cpp
try {
__builtin_wasm_throw(0, obj);
} catch (...) {
}
```
does not generate `invoke`. This is because we have assumed the
intrinsic cannot be invoked, which doesn't make much sense. (See #128104
for the historical context)
#128104 made `llvm.wasm.throw` intrinsic invokable in the backend. This
actually generates `invoke`s in Clang for `__builtin_wasm_throw`.
While we're at it, this also generates `invoke`s for
`__builtin_wasm_rethrow`, which is actually not used anywhere in C++
support. I haven't deleted it just in case in may have uses later. (For
example, to support rethrow functionality that carries stack trace with
exnref)
Depends on #128104 for the CI to pass.
Fixes #124710.
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llvm.wasm.throwintrinsic can throw but it was not invokable. Not sure what the rationale was when it was first written that way, but I think at least in Emscripten's C++ exception support with the Wasm port of libunwind,__builtin_wasm_throw, which is lowered down tollvm.wasm.rethrow, is used only within_Unwind_RaiseException, which is an one-liner and thus does not need aninvoke: https://github.com/emscripten-core/emscripten/blob/720e97f76d6f19e0c6a2d6988988cfe23f0517fb/system/lib/libunwind/src/Unwind-wasm.c#L69 (_Unwind_RaiseExceptionis called by__cxa_throw, which is generated by thethrowC++ keyword)But this does not address other direct uses of the builtin in C++, whose use I'm not sure about but is not prohibited. Also other language frontends may need to use the builtin in different functions, which has
try-catches or destructors.This makes
llvm.wasm.throwinvokable in the backend. To do that, this adds a custom lowering routine toSelectionDAGBuilder::visitInvoke, like we did forllvm.wasm.rethrow.This does not generate
invokes for__builtin_wasm_throwyet, which will be done by a follow-up PR.Addresses #124710.