[WebAssembly] Make rethrow take an except_ref type argument

Summary:
In the new wasm EH proposal, `rethrow` takes an `except_ref` argument.
This change was missing in r352598.

This patch adds `llvm.wasm.rethrow.in.catch` intrinsic. This is an
intrinsic that's gonna eventually be lowered to wasm `rethrow`
instruction, but this intrinsic can appear only within a catchpad or a
cleanuppad scope. Also this intrinsic needs to be invokable - otherwise
EH pad successor for it will not be correctly generated in clang.

This also adds lowering logic for this intrinsic in
`SelectionDAGBuilder::visitInvoke`. This routine is basically a
specialized and simplified version of
`SelectionDAGBuilder::visitTargetIntrinsic`, but we can't use it
because if is only for `CallInst`s.

This deletes the previous `llvm.wasm.rethrow` intrinsic and related
tests, which was meant to be used within a `__cxa_rethrow` library
function. Turned out this needs some more logic, so the intrinsic for
this purpose will be added later.

LateEHPrepare takes a result value of `catch` and inserts it into
matching `rethrow` as an argument.

`RETHROW_IN_CATCH` is a pseudo instruction that serves as a link between
`llvm.wasm.rethrow.in.catch` and the real wasm `rethrow` instruction. To
generate a `rethrow` instruction, we need an `except_ref` argument,
which is generated from `catch` instruction. But `catch` instrutions are
added in LateEHPrepare pass, so we use `RETHROW_IN_CATCH`, which takes
no argument, until we are able to correctly lower it to `rethrow` in
LateEHPrepare.

Reviewers: dschuff

Subscribers: sbc100, jgravelle-google, sunfish, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59352

llvm-svn: 356316

9 files changed, 85 insertions, 102 deletions

diff --git a/llvm/include/llvm/IR/IntrinsicsWebAssembly.td b/llvm/include/llvm/IR/IntrinsicsWebAssembly.td
index bfeb7063ced..598349f7f04 100644
--- a/llvm/include/llvm/IR/IntrinsicsWebAssembly.td
+++ b/llvm/include/llvm/IR/IntrinsicsWebAssembly.td
@@ -41,7 +41,7 @@ def int_wasm_trunc_saturate_unsigned : Intrinsic<[llvm_anyint_ty],
 // throw / rethrow
 def int_wasm_throw : Intrinsic<[], [llvm_i32_ty, llvm_ptr_ty],
                                [Throws, IntrNoReturn]>;
-def int_wasm_rethrow : Intrinsic<[], [], [Throws, IntrNoReturn]>;
+def int_wasm_rethrow_in_catch : Intrinsic<[], [], [Throws, IntrNoReturn]>;
 
 // Since wasm does not use landingpad instructions, these instructions return
 // exception pointer and selector values until we lower them in WasmEHPrepare.
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 31768b2f9b2..6a88948ac6b 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -2697,6 +2697,20 @@ void SelectionDAGBuilder::visitInvoke(const InvokeInst &I) {
     case Intrinsic::experimental_gc_statepoint:
       LowerStatepoint(ImmutableStatepoint(&I), EHPadBB);
       break;
+    case Intrinsic::wasm_rethrow_in_catch: {
+      // 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(getRoot()); // inchain
+      const TargetLowering &TLI = DAG.getTargetLoweringInfo();
+      Ops.push_back(
+          DAG.getTargetConstant(Intrinsic::wasm_rethrow_in_catch, getCurSDLoc(),
+                                TLI.getPointerTy(DAG.getDataLayout())));
+      SDVTList VTs = DAG.getVTList(ArrayRef<EVT>({MVT::Other})); // outchain
+      DAG.setRoot(DAG.getNode(ISD::INTRINSIC_VOID, getCurSDLoc(), VTs, Ops));
+      break;
+    }
     }
   } else if (I.countOperandBundlesOfType(LLVMContext::OB_deopt)) {
     // Currently we do not lower any intrinsic calls with deopt operand bundles.
diff --git a/llvm/lib/CodeGen/WasmEHPrepare.cpp b/llvm/lib/CodeGen/WasmEHPrepare.cpp
index a58da13d9b0..865a1cfbf43 100644
--- a/llvm/lib/CodeGen/WasmEHPrepare.cpp
+++ b/llvm/lib/CodeGen/WasmEHPrepare.cpp
@@ -104,15 +104,14 @@ class WasmEHPrepare : public FunctionPass {
   Value *LSDAField = nullptr;      // lsda field
   Value *SelectorField = nullptr;  // selector
 
-  Function *ThrowF = nullptr;           // wasm.throw() intrinsic
-  Function *RethrowF = nullptr;         // wasm.rethrow() intrinsic
-  Function *LPadIndexF = nullptr;       // wasm.landingpad.index() intrinsic
-  Function *LSDAF = nullptr;            // wasm.lsda() intrinsic
-  Function *GetExnF = nullptr;          // wasm.get.exception() intrinsic
-  Function *ExtractExnF = nullptr;      // wasm.extract.exception() intrinsic
-  Function *GetSelectorF = nullptr;     // wasm.get.ehselector() intrinsic
+  Function *ThrowF = nullptr;       // wasm.throw() intrinsic
+  Function *LPadIndexF = nullptr;   // wasm.landingpad.index() intrinsic
+  Function *LSDAF = nullptr;        // wasm.lsda() intrinsic
+  Function *GetExnF = nullptr;      // wasm.get.exception() intrinsic
+  Function *ExtractExnF = nullptr;  // wasm.extract.exception() intrinsic
+  Function *GetSelectorF = nullptr; // wasm.get.ehselector() intrinsic
   FunctionCallee CallPersonalityF =
-      nullptr;                          // _Unwind_CallPersonality() wrapper
+      nullptr; // _Unwind_CallPersonality() wrapper
 
   bool prepareEHPads(Function &F);
   bool prepareThrows(Function &F);
@@ -177,29 +176,23 @@ bool WasmEHPrepare::prepareThrows(Function &F) {
 
   // wasm.throw() intinsic, which will be lowered to wasm 'throw' instruction.
   ThrowF = Intrinsic::getDeclaration(&M, Intrinsic::wasm_throw);
-  // wasm.rethrow() intinsic, which will be lowered to wasm 'rethrow'
-  // instruction.
-  RethrowF = Intrinsic::getDeclaration(&M, Intrinsic::wasm_rethrow);
-
-  // Insert an unreachable instruction after a call to @llvm.wasm.throw /
-  // @llvm.wasm.rethrow and delete all following instructions within the BB, and
-  // delete all the dead children of the BB as well.
-  for (auto L : {ThrowF->users(), RethrowF->users()}) {
-    for (User *U : L) {
-      // 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)
-        continue;
-      Changed = true;
-      auto *BB = ThrowI->getParent();
-      SmallVector<BasicBlock *, 4> Succs(succ_begin(BB), succ_end(BB));
-      auto &InstList = BB->getInstList();
-      InstList.erase(std::next(BasicBlock::iterator(ThrowI)), InstList.end());
-      IRB.SetInsertPoint(BB);
-      IRB.CreateUnreachable();
-      eraseDeadBBsAndChildren(Succs);
-    }
+  // Insert an unreachable instruction after a call to @llvm.wasm.throw and
+  // 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)
+      continue;
+    Changed = true;
+    auto *BB = ThrowI->getParent();
+    SmallVector<BasicBlock *, 4> Succs(succ_begin(BB), succ_end(BB));
+    auto &InstList = BB->getInstList();
+    InstList.erase(std::next(BasicBlock::iterator(ThrowI)), InstList.end());
+    IRB.SetInsertPoint(BB);
+    IRB.CreateUnreachable();
+    eraseDeadBBsAndChildren(Succs);
   }
 
   return Changed;
diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index 2ef091b7666..ae76e315bf5 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -4026,7 +4026,8 @@ void Verifier::visitInstruction(Instruction &I) {
               F->getIntrinsicID() == Intrinsic::coro_destroy ||
               F->getIntrinsicID() == Intrinsic::experimental_patchpoint_void ||
               F->getIntrinsicID() == Intrinsic::experimental_patchpoint_i64 ||
-              F->getIntrinsicID() == Intrinsic::experimental_gc_statepoint,
+              F->getIntrinsicID() == Intrinsic::experimental_gc_statepoint ||
+              F->getIntrinsicID() == Intrinsic::wasm_rethrow_in_catch,
           "Cannot invoke an intrinsic other than donothing, patchpoint, "
           "statepoint, coro_resume or coro_destroy",
           &I);
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyInstrControl.td b/llvm/lib/Target/WebAssembly/WebAssemblyInstrControl.td
index d44458f790a..574cb09ff33 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyInstrControl.td
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyInstrControl.td
@@ -144,7 +144,13 @@ defm THROW : I<(outs), (ins event_op:$tag, variable_ops),
                (outs), (ins event_op:$tag),
                [(WebAssemblythrow (WebAssemblywrapper texternalsym:$tag))],
                "throw   \t$tag", "throw   \t$tag", 0x08>;
-defm RETHROW : NRI<(outs), (ins), [(int_wasm_rethrow)], "rethrow", 0x09>;
+defm RETHROW : I<(outs), (ins EXCEPT_REF:$exn), (outs), (ins),
+                 [], "rethrow \t$exn", "rethrow", 0x09>;
+// Pseudo instruction to be the lowering target of int_wasm_rethrow_in_catch
+// intrinsic. Will be converted to the real rethrow instruction later.
+let isPseudo = 1 in
+defm RETHROW_IN_CATCH : NRI<(outs), (ins), [(int_wasm_rethrow_in_catch)],
+                            "rethrow_in_catch", 0>;
 } // isTerminator = 1, hasCtrlDep = 1, isBarrier = 1
 
 // Region within which an exception is caught: try / end_try
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyLateEHPrepare.cpp b/llvm/lib/Target/WebAssembly/WebAssemblyLateEHPrepare.cpp
index 5b6fdb86c6d..f365aa73792 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyLateEHPrepare.cpp
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyLateEHPrepare.cpp
@@ -161,9 +161,17 @@ bool WebAssemblyLateEHPrepare::replaceFuncletReturns(MachineFunction &MF) {
       Changed = true;
       break;
     }
-    case WebAssembly::CLEANUPRET: {
-      // Replace a cleanupret with a rethrow
-      BuildMI(MBB, TI, TI->getDebugLoc(), TII.get(WebAssembly::RETHROW));
+    case WebAssembly::CLEANUPRET:
+    case WebAssembly::RETHROW_IN_CATCH: {
+      // Replace a cleanupret/rethrow_in_catch with a rethrow
+      auto *EHPad = getMatchingEHPad(TI);
+      auto CatchPos = EHPad->begin();
+      if (CatchPos->isEHLabel()) // EH pad starts with an EH label
+        ++CatchPos;
+      MachineInstr *Catch = &*CatchPos;
+      unsigned ExnReg = Catch->getOperand(0).getReg();
+      BuildMI(MBB, TI, TI->getDebugLoc(), TII.get(WebAssembly::RETHROW))
+          .addReg(ExnReg);
       TI->eraseFromParent();
       Changed = true;
       break;
@@ -191,7 +199,8 @@ bool WebAssemblyLateEHPrepare::removeUnnecessaryUnreachables(
       SmallVector<MachineBasicBlock *, 8> Succs(MBB.succ_begin(),
                                                 MBB.succ_end());
       for (auto *Succ : Succs)
-        MBB.removeSuccessor(Succ);
+        if (!Succ->isEHPad())
+          MBB.removeSuccessor(Succ);
       eraseDeadBBsAndChildren(Succs);
     }
   }
@@ -337,7 +346,7 @@ bool WebAssemblyLateEHPrepare::addExceptionExtraction(MachineFunction &MF) {
       BuildMI(ElseMBB, DL, TII.get(WebAssembly::UNREACHABLE));
 
     } else {
-      BuildMI(ElseMBB, DL, TII.get(WebAssembly::RETHROW));
+      BuildMI(ElseMBB, DL, TII.get(WebAssembly::RETHROW)).addReg(ExnReg);
       if (EHInfo->hasEHPadUnwindDest(EHPad))
         ElseMBB->addSuccessor(EHInfo->getEHPadUnwindDest(EHPad));
     }
diff --git a/llvm/test/CodeGen/WebAssembly/cfg-stackify-eh.ll b/llvm/test/CodeGen/WebAssembly/cfg-stackify-eh.ll
index 01bac8e63d1..5b06a0baa35 100644
--- a/llvm/test/CodeGen/WebAssembly/cfg-stackify-eh.ll
+++ b/llvm/test/CodeGen/WebAssembly/cfg-stackify-eh.ll
@@ -33,7 +33,7 @@ target triple = "wasm32-unknown-unknown"
 ; CHECK:     call      __cxa_end_catch
 ; CHECK:     br        1                               # 1: down to label0
 ; CHECK:   end_block                                   # label3:
-; CHECK:   call      __cxa_rethrow
+; CHECK:   rethrow   {{.*}}                            # to caller
 ; CHECK: end_try                                       # label0:
 define void @test0() personality i8* bitcast (i32 (...)* @__gxx_wasm_personality_v0 to i8*) {
 entry:
@@ -67,7 +67,7 @@ catch:                                            ; preds = %catch.fallthrough
   catchret from %1 to label %try.cont
 
 rethrow:                                          ; preds = %catch.fallthrough
-  call void @__cxa_rethrow() [ "funclet"(token %1) ]
+  call void @llvm.wasm.rethrow.in.catch() [ "funclet"(token %1) ]
   unreachable
 
 try.cont:                                         ; preds = %entry, %catch, %catch2
@@ -108,21 +108,19 @@ try.cont:                                         ; preds = %entry, %catch, %cat
 ; CHECK:               br        2                     # 2: down to label9
 ; CHECK:             catch
 ; CHECK:               call      __cxa_end_catch
-; CHECK:               rethrow                         # down to catch3
+; CHECK:               rethrow   {{.*}}                # down to catch3
 ; CHECK:             end_try
 ; CHECK:           end_block                           # label11:
-; CHECK:           call      __cxa_rethrow
-; CHECK:           unreachable
+; CHECK:           rethrow   {{.*}}                    # down to catch3
 ; CHECK:         catch     {{.*}}                      # catch3:
 ; CHECK:           call      __cxa_end_catch
-; CHECK:           rethrow                             # to caller
+; CHECK:           rethrow   {{.*}}                    # to caller
 ; CHECK:         end_try                               # label9:
 ; CHECK:         call      __cxa_end_catch
 ; CHECK:         br        2                           # 2: down to label6
 ; CHECK:       end_try
 ; CHECK:     end_block                                 # label7:
-; CHECK:     call      __cxa_rethrow
-; CHECK:     unreachable
+; CHECK:     rethrow   {{.*}}                          # to caller
 ; CHECK:   end_block                                   # label6:
 ; CHECK:   call      __cxa_end_catch
 ; CHECK: end_try
@@ -172,7 +170,7 @@ invoke.cont8:                                     ; preds = %catch6
   catchret from %9 to label %try.cont
 
 rethrow5:                                         ; preds = %catch.start3
-  invoke void @__cxa_rethrow() [ "funclet"(token %9) ]
+  invoke void @llvm.wasm.rethrow.in.catch() [ "funclet"(token %9) ]
           to label %unreachable unwind label %ehcleanup9
 
 try.cont:                                         ; preds = %catch, %invoke.cont8
@@ -180,7 +178,7 @@ try.cont:                                         ; preds = %catch, %invoke.cont
   catchret from %1 to label %try.cont11
 
 rethrow:                                          ; preds = %catch.start
-  call void @__cxa_rethrow() [ "funclet"(token %1) ]
+  call void @llvm.wasm.rethrow.in.catch() [ "funclet"(token %1) ]
   unreachable
 
 try.cont11:                                       ; preds = %entry, %try.cont
@@ -229,7 +227,7 @@ unreachable:                                      ; preds = %rethrow5
 ; CHECK:             call      __clang_call_terminate
 ; CHECK:             unreachable
 ; CHECK:           end_try
-; CHECK:           rethrow                             # to caller
+; CHECK:           rethrow   {{.*}}                    # to caller
 ; CHECK:         end_try
 ; CHECK:       end_block                               # label17:
 ; CHECK:       call      __cxa_end_catch
@@ -293,9 +291,9 @@ declare void @bar()
 declare i32 @__gxx_wasm_personality_v0(...)
 declare i8* @llvm.wasm.get.exception(token)
 declare i32 @llvm.wasm.get.ehselector(token)
+declare void @llvm.wasm.rethrow.in.catch()
 declare i32 @llvm.eh.typeid.for(i8*)
 declare i8* @__cxa_begin_catch(i8*)
 declare void @__cxa_end_catch()
-declare void @__cxa_rethrow()
 declare void @__clang_call_terminate(i8*)
 declare void @_ZSt9terminatev()
diff --git a/llvm/test/CodeGen/WebAssembly/exception.ll b/llvm/test/CodeGen/WebAssembly/exception.ll
index f41588faa61..8f7687e2da4 100644
--- a/llvm/test/CodeGen/WebAssembly/exception.ll
+++ b/llvm/test/CodeGen/WebAssembly/exception.ll
@@ -17,14 +17,6 @@ define void @test_throw(i8* %p) {
   ret void
 }
 
-; CHECK-LABEL: test_rethrow:
-; CHECK:     rethrow
-; CHECK-NOT: unreachable
-define void @test_rethrow(i8* %p) {
-  call void @llvm.wasm.rethrow()
-  ret void
-}
-
 ; Simple test with a try-catch
 ;
 ; void foo();
@@ -43,7 +35,7 @@ define void @test_rethrow(i8* %p) {
 ; CHECK:       global.set  __stack_pointer
 ; CHECK:       block i32
 ; CHECK:         br_on_exn 0, __cpp_exception, $[[EXCEPT_REF]]
-; CHECK:         rethrow
+; CHECK:         rethrow   $[[EXCEPT_REF]]
 ; CHECK:       end_block
 ; CHECK:       extract_exception $[[EXN:[0-9]+]]=
 ; CHECK-DAG:   i32.store  __wasm_lpad_context
@@ -55,7 +47,7 @@ define void @test_rethrow(i8* %p) {
 ; CHECK:         call      __cxa_end_catch
 ; CHECK:         br        1
 ; CHECK:       end_block
-; CHECK:       call      __cxa_rethrow
+; CHECK:       rethrow   $[[EXCEPT_REF]]
 ; CHECK:     end_try
 define void @test_catch() personality i8* bitcast (i32 (...)* @__gxx_wasm_personality_v0 to i8*) {
 entry:
@@ -79,7 +71,7 @@ catch:                                            ; preds = %catch.start
   catchret from %1 to label %try.cont
 
 rethrow:                                          ; preds = %catch.start
-  call void @__cxa_rethrow() [ "funclet"(token %1) ]
+  call void @llvm.wasm.rethrow.in.catch() [ "funclet"(token %1) ]
   unreachable
 
 try.cont:                                         ; preds = %entry, %catch
@@ -100,10 +92,10 @@ try.cont:                                         ; preds = %entry, %catch
 ; CHECK-LABEL: test_cleanup:
 ; CHECK: try
 ; CHECK:   call      foo
-; CHECK: catch
+; CHECK: catch     $[[EXCEPT_REF:[0-9]+]]=
 ; CHECK:   global.set  __stack_pointer
 ; CHECK:   i32.call  $drop=, _ZN4TempD2Ev
-; CHECK:   rethrow
+; CHECK:   rethrow   $[[EXCEPT_REF]]
 ; CHECK: end_try
 define void @test_cleanup() personality i8* bitcast (i32 (...)* @__gxx_wasm_personality_v0 to i8*) {
 entry:
@@ -231,7 +223,7 @@ terminate:                                        ; preds = %ehcleanup
 ; CHECK-NOT:         global.set  __stack_pointer, $pop{{.+}}
 ; CHECK:           end_try
 ; CHECK:         end_block
-; CHECK:         call      __cxa_rethrow
+; CHECK:         rethrow
 ; CHECK:       end_block
 ; CHECK-NOT:   global.set  __stack_pointer, $pop{{.+}}
 ; CHECK:       call      __cxa_end_catch
@@ -266,7 +258,7 @@ invoke.cont1:                                     ; preds = %catch
   catchret from %1 to label %try.cont
 
 rethrow:                                          ; preds = %catch.start
-  call void @__cxa_rethrow() [ "funclet"(token %1) ]
+  call void @llvm.wasm.rethrow.in.catch() [ "funclet"(token %1) ]
   unreachable
 
 try.cont:                                         ; preds = %entry, %invoke.cont1
@@ -342,13 +334,12 @@ declare void @foo()
 declare void @bar(i32*)
 declare i32 @__gxx_wasm_personality_v0(...)
 declare void @llvm.wasm.throw(i32, i8*)
-declare void @llvm.wasm.rethrow()
 declare i8* @llvm.wasm.get.exception(token)
 declare i32 @llvm.wasm.get.ehselector(token)
+declare void @llvm.wasm.rethrow.in.catch()
 declare i32 @llvm.eh.typeid.for(i8*)
 declare i8* @__cxa_begin_catch(i8*)
 declare void @__cxa_end_catch()
-declare void @__cxa_rethrow()
 declare void @__clang_call_terminate(i8*)
 declare %struct.Temp* @_ZN4TempD2Ev(%struct.Temp* returned)
 
diff --git a/llvm/test/CodeGen/WebAssembly/wasmehprepare.ll b/llvm/test/CodeGen/WebAssembly/wasmehprepare.ll
index b4699efbf89..d06f95fd39c 100644
--- a/llvm/test/CodeGen/WebAssembly/wasmehprepare.ll
+++ b/llvm/test/CodeGen/WebAssembly/wasmehprepare.ll
@@ -54,7 +54,7 @@ catch:                                            ; preds = %catch.start
 ; CHECK-NEXT:  call i8* @__cxa_begin_catch(i8* %[[EXN]])
 
 rethrow:                                          ; preds = %catch.start
-  call void @__cxa_rethrow() [ "funclet"(token %1) ]
+  call void @llvm.wasm.rethrow.in.catch() [ "funclet"(token %1) ]
   unreachable
 
 try.cont:                                         ; preds = %entry, %catch
@@ -125,7 +125,7 @@ catch4:                                           ; preds = %catch.start3
   catchret from %6 to label %try.cont7
 
 rethrow:                                          ; preds = %catch.start3
-  call void @__cxa_rethrow() [ "funclet"(token %6) ]
+  call void @llvm.wasm.rethrow.in.catch() [ "funclet"(token %6) ]
   unreachable
 
 try.cont7:                                        ; preds = %try.cont, %catch4
@@ -189,7 +189,7 @@ catch6:                                           ; preds = %catch.start3
   catchret from %7 to label %try.cont
 
 rethrow5:                                         ; preds = %catch.start3
-  invoke void @__cxa_rethrow() [ "funclet"(token %7) ]
+  invoke void @llvm.wasm.rethrow.in.catch() [ "funclet"(token %7) ]
           to label %unreachable unwind label %ehcleanup
 
 try.cont:                                         ; preds = %catch, %catch6
@@ -197,7 +197,7 @@ try.cont:                                         ; preds = %catch, %catch6
   catchret from %1 to label %try.cont9
 
 rethrow:                                          ; preds = %catch.start
-  call void @__cxa_rethrow() [ "funclet"(token %1) ]
+  call void @llvm.wasm.rethrow.in.catch() [ "funclet"(token %1) ]
   unreachable
 
 try.cont9:                                        ; preds = %entry, %try.cont
@@ -392,34 +392,6 @@ merge:                                            ; preds = %bb.true.0, %bb.fals
   ret i32 0
 }
 
-; Tests if instructions after a call to @llvm.wasm.rethrow are deleted and the
-; BB's dead children are deleted.
-
-; CHECK-LABEL: @test6
-define i32 @test6(i1 %b, i8* %p) {
-entry:
-  br i1 %b, label %bb.true, label %bb.false
-
-; CHECK:      bb.true:
-; CHECK-NEXT:   call void @llvm.wasm.rethrow()
-; CHECK-NEXT:   unreachable
-bb.true:                                          ; preds = %entry
-  call void @llvm.wasm.rethrow()
-  br label %bb.true.0
-
-; CHECK-NOT:  bb.true.0
-bb.true.0:                                        ; preds = %bb.true
-  br label %merge
-
-; CHECK:      bb.false
-bb.false:                                         ; preds = %entry
-  br label %merge
-
-; CHECK:      merge
-merge:                                            ; preds = %bb.true.0, %bb.false
-  ret i32 0
-}
-
 declare void @foo()
 declare void @bar(i32)
 declare %struct.Temp* @_ZN4TempD2Ev(%struct.Temp* returned)
@@ -428,10 +400,9 @@ declare i8* @llvm.wasm.get.exception(token)
 declare i32 @llvm.wasm.get.ehselector(token)
 declare i32 @llvm.eh.typeid.for(i8*)
 declare void @llvm.wasm.throw(i32, i8*)
-declare void @llvm.wasm.rethrow()
+declare void @llvm.wasm.rethrow.in.catch()
 declare i8* @__cxa_begin_catch(i8*)
 declare void @__cxa_end_catch()
-declare void @__cxa_rethrow()
 declare void @__clang_call_terminate(i8*)
 
 ; CHECK-DAG: declare void @llvm.wasm.landingpad.index(token, i32)