[llvm] r335438 - [WebAssembly] Add WebAssemblyLateEHPrepare pass
Heejin Ahn via llvm-commits
llvm-commits at lists.llvm.org
Sun Jun 24 18:07:12 PDT 2018
Author: aheejin
Date: Sun Jun 24 18:07:11 2018
New Revision: 335438
URL: http://llvm.org/viewvc/llvm-project?rev=335438&view=rev
Log:
[WebAssembly] Add WebAssemblyLateEHPrepare pass
Summary:
Add WebAssemblyLateEHPrepare pass that does several small jobs for
exception handling. This runs before CFGSort, and is different from
WasmEHPrepare pass that runs before ISel, even though the names are
similar.
Reviewers: dschuff, majnemer
Subscribers: sbc100, jgravelle-google, sunfish, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D46803
Added:
llvm/trunk/lib/Target/WebAssembly/WebAssemblyLateEHPrepare.cpp
Removed:
llvm/trunk/lib/Target/WebAssembly/WebAssemblyExceptionPrepare.cpp
Modified:
llvm/trunk/lib/Target/WebAssembly/CMakeLists.txt
llvm/trunk/lib/Target/WebAssembly/WebAssembly.h
llvm/trunk/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp
llvm/trunk/test/CodeGen/WebAssembly/exception.ll
Modified: llvm/trunk/lib/Target/WebAssembly/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/WebAssembly/CMakeLists.txt?rev=335438&r1=335437&r2=335438&view=diff
==============================================================================
--- llvm/trunk/lib/Target/WebAssembly/CMakeLists.txt (original)
+++ llvm/trunk/lib/Target/WebAssembly/CMakeLists.txt Sun Jun 24 18:07:11 2018
@@ -18,7 +18,7 @@ add_llvm_target(WebAssemblyCodeGen
WebAssemblyCallIndirectFixup.cpp
WebAssemblyCFGStackify.cpp
WebAssemblyCFGSort.cpp
- WebAssemblyExceptionPrepare.cpp
+ WebAssemblyLateEHPrepare.cpp
WebAssemblyExplicitLocals.cpp
WebAssemblyFastISel.cpp
WebAssemblyFixIrreducibleControlFlow.cpp
Modified: llvm/trunk/lib/Target/WebAssembly/WebAssembly.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/WebAssembly/WebAssembly.h?rev=335438&r1=335437&r2=335438&view=diff
==============================================================================
--- llvm/trunk/lib/Target/WebAssembly/WebAssembly.h (original)
+++ llvm/trunk/lib/Target/WebAssembly/WebAssembly.h Sun Jun 24 18:07:11 2018
@@ -46,7 +46,7 @@ FunctionPass *createWebAssemblyRegStacki
FunctionPass *createWebAssemblyRegColoring();
FunctionPass *createWebAssemblyExplicitLocals();
FunctionPass *createWebAssemblyFixIrreducibleControlFlow();
-FunctionPass *createWebAssemblyExceptionPrepare();
+FunctionPass *createWebAssemblyLateEHPrepare();
FunctionPass *createWebAssemblyCFGSort();
FunctionPass *createWebAssemblyCFGStackify();
FunctionPass *createWebAssemblyLowerBrUnless();
@@ -69,7 +69,7 @@ void initializeWebAssemblyRegStackifyPas
void initializeWebAssemblyRegColoringPass(PassRegistry &);
void initializeWebAssemblyExplicitLocalsPass(PassRegistry &);
void initializeWebAssemblyFixIrreducibleControlFlowPass(PassRegistry &);
-void initializeWebAssemblyExceptionPreparePass(PassRegistry &);
+void initializeWebAssemblyLateEHPreparePass(PassRegistry &);
void initializeWebAssemblyCFGSortPass(PassRegistry &);
void initializeWebAssemblyCFGStackifyPass(PassRegistry &);
void initializeWebAssemblyLowerBrUnlessPass(PassRegistry &);
Removed: llvm/trunk/lib/Target/WebAssembly/WebAssemblyExceptionPrepare.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/WebAssembly/WebAssemblyExceptionPrepare.cpp?rev=335437&view=auto
==============================================================================
--- llvm/trunk/lib/Target/WebAssembly/WebAssemblyExceptionPrepare.cpp (original)
+++ llvm/trunk/lib/Target/WebAssembly/WebAssemblyExceptionPrepare.cpp (removed)
@@ -1,88 +0,0 @@
-//=== WebAssemblyExceptionPrepare.cpp - WebAssembly Exception Preparation -===//
-//
-// The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-///
-/// \file
-/// \brief Does various transformations for exception handling.
-///
-//===----------------------------------------------------------------------===//
-
-#include "MCTargetDesc/WebAssemblyMCTargetDesc.h"
-#include "WebAssembly.h"
-#include "WebAssemblySubtarget.h"
-#include "llvm/CodeGen/MachineInstrBuilder.h"
-using namespace llvm;
-
-#define DEBUG_TYPE "wasm-exception-prepare"
-
-namespace {
-class WebAssemblyExceptionPrepare final : public MachineFunctionPass {
- StringRef getPassName() const override {
- return "WebAssembly Prepare Exception";
- }
-
- bool runOnMachineFunction(MachineFunction &MF) override;
-
- bool replaceFuncletReturns(MachineFunction &MF);
-
-public:
- static char ID; // Pass identification, replacement for typeid
- WebAssemblyExceptionPrepare() : MachineFunctionPass(ID) {}
-};
-} // end anonymous namespace
-
-char WebAssemblyExceptionPrepare::ID = 0;
-INITIALIZE_PASS(WebAssemblyExceptionPrepare, DEBUG_TYPE,
- "WebAssembly Exception Preparation", false, false)
-
-FunctionPass *llvm::createWebAssemblyExceptionPrepare() {
- return new WebAssemblyExceptionPrepare();
-}
-
-bool WebAssemblyExceptionPrepare::runOnMachineFunction(MachineFunction &MF) {
- bool Changed = false;
- if (!MF.getFunction().hasPersonalityFn())
- return false;
- Changed |= replaceFuncletReturns(MF);
- // TODO More transformations will be added
- return Changed;
-}
-
-bool WebAssemblyExceptionPrepare::replaceFuncletReturns(MachineFunction &MF) {
- bool Changed = false;
- const auto &TII = *MF.getSubtarget<WebAssemblySubtarget>().getInstrInfo();
-
- for (auto &MBB : MF) {
- auto Pos = MBB.getFirstTerminator();
- if (Pos == MBB.end())
- continue;
- MachineInstr *TI = &*Pos;
-
- switch (TI->getOpcode()) {
- case WebAssembly::CATCHRET: {
- // Replace a catchret with a branch
- MachineBasicBlock *TBB = TI->getOperand(0).getMBB();
- if (!MBB.isLayoutSuccessor(TBB))
- BuildMI(MBB, TI, TI->getDebugLoc(), TII.get(WebAssembly::BR))
- .addMBB(TBB);
- TI->eraseFromParent();
- Changed = true;
- break;
- }
- case WebAssembly::CLEANUPRET: {
- // Replace a cleanupret with a rethrow
- BuildMI(MBB, TI, TI->getDebugLoc(), TII.get(WebAssembly::RETHROW))
- .addImm(0);
- TI->eraseFromParent();
- Changed = true;
- break;
- }
- }
- }
- return Changed;
-}
Added: llvm/trunk/lib/Target/WebAssembly/WebAssemblyLateEHPrepare.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/WebAssembly/WebAssemblyLateEHPrepare.cpp?rev=335438&view=auto
==============================================================================
--- llvm/trunk/lib/Target/WebAssembly/WebAssemblyLateEHPrepare.cpp (added)
+++ llvm/trunk/lib/Target/WebAssembly/WebAssemblyLateEHPrepare.cpp Sun Jun 24 18:07:11 2018
@@ -0,0 +1,383 @@
+//=== WebAssemblyLateEHPrepare.cpp - WebAssembly Exception Preparation -===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// \brief Does various transformations for exception handling.
+///
+//===----------------------------------------------------------------------===//
+
+#include "MCTargetDesc/WebAssemblyMCTargetDesc.h"
+#include "WebAssembly.h"
+#include "WebAssemblySubtarget.h"
+#include "WebAssemblyUtilities.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/WasmEHFuncInfo.h"
+#include "llvm/MC/MCAsmInfo.h"
+using namespace llvm;
+
+#define DEBUG_TYPE "wasm-exception-prepare"
+
+namespace {
+class WebAssemblyLateEHPrepare final : public MachineFunctionPass {
+ StringRef getPassName() const override {
+ return "WebAssembly Prepare Exception";
+ }
+
+ bool runOnMachineFunction(MachineFunction &MF) override;
+
+ bool replaceFuncletReturns(MachineFunction &MF);
+ bool hoistCatches(MachineFunction &MF);
+ bool addCatchAlls(MachineFunction &MF);
+ bool addRethrows(MachineFunction &MF);
+ bool ensureSingleBBTermPads(MachineFunction &MF);
+ bool mergeTerminatePads(MachineFunction &MF);
+ bool addCatchAllTerminatePads(MachineFunction &MF);
+
+public:
+ static char ID; // Pass identification, replacement for typeid
+ WebAssemblyLateEHPrepare() : MachineFunctionPass(ID) {}
+};
+} // end anonymous namespace
+
+char WebAssemblyLateEHPrepare::ID = 0;
+INITIALIZE_PASS(WebAssemblyLateEHPrepare, DEBUG_TYPE,
+ "WebAssembly Exception Preparation", false, false)
+
+FunctionPass *llvm::createWebAssemblyLateEHPrepare() {
+ return new WebAssemblyLateEHPrepare();
+}
+
+// Returns the nearest EH pad that dominates this instruction. This does not use
+// dominator analysis; it just does BFS on its predecessors until arriving at an
+// EH pad. This assumes valid EH scopes so the first EH pad it arrives in all
+// possible search paths should be the same.
+// Returns nullptr in case it does not find any EH pad in the search, or finds
+// multiple different EH pads.
+MachineBasicBlock *GetMatchingEHPad(MachineInstr *MI) {
+ MachineFunction *MF = MI->getParent()->getParent();
+ SmallVector<MachineBasicBlock *, 2> WL;
+ SmallPtrSet<MachineBasicBlock *, 2> Visited;
+ WL.push_back(MI->getParent());
+ MachineBasicBlock *EHPad = nullptr;
+ while (!WL.empty()) {
+ MachineBasicBlock *MBB = WL.pop_back_val();
+ if (Visited.count(MBB))
+ continue;
+ Visited.insert(MBB);
+ if (MBB->isEHPad()) {
+ if (EHPad && EHPad != MBB)
+ return nullptr;
+ EHPad = MBB;
+ continue;
+ }
+ if (MBB == &MF->front())
+ return nullptr;
+ WL.append(MBB->pred_begin(), MBB->pred_end());
+ }
+ return EHPad;
+}
+
+// Erases the given BB and all its children from the function. If other BBs have
+// this BB as a successor, the successor relationships will be deleted as well.
+static void EraseBBAndChildren(MachineBasicBlock *MBB) {
+ SmallVector<MachineBasicBlock *, 8> WL;
+ WL.push_back(MBB);
+ while (!WL.empty()) {
+ MachineBasicBlock *MBB = WL.pop_back_val();
+ for (auto *Pred : MBB->predecessors())
+ Pred->removeSuccessor(MBB);
+ for (auto *Succ : MBB->successors()) {
+ WL.push_back(Succ);
+ MBB->removeSuccessor(Succ);
+ }
+ MBB->eraseFromParent();
+ }
+}
+
+bool WebAssemblyLateEHPrepare::runOnMachineFunction(MachineFunction &MF) {
+ if (MF.getTarget().getMCAsmInfo()->getExceptionHandlingType() !=
+ ExceptionHandling::Wasm)
+ return false;
+
+ bool Changed = false;
+ Changed |= addRethrows(MF);
+ if (!MF.getFunction().hasPersonalityFn())
+ return Changed;
+ Changed |= replaceFuncletReturns(MF);
+ Changed |= hoistCatches(MF);
+ Changed |= addCatchAlls(MF);
+ Changed |= ensureSingleBBTermPads(MF);
+ Changed |= mergeTerminatePads(MF);
+ Changed |= addCatchAllTerminatePads(MF);
+ return Changed;
+}
+
+bool WebAssemblyLateEHPrepare::replaceFuncletReturns(MachineFunction &MF) {
+ bool Changed = false;
+ const auto &TII = *MF.getSubtarget<WebAssemblySubtarget>().getInstrInfo();
+ auto *EHInfo = MF.getWasmEHFuncInfo();
+
+ for (auto &MBB : MF) {
+ auto Pos = MBB.getFirstTerminator();
+ if (Pos == MBB.end())
+ continue;
+ MachineInstr *TI = &*Pos;
+
+ switch (TI->getOpcode()) {
+ case WebAssembly::CATCHRET: {
+ // Replace a catchret with a branch
+ MachineBasicBlock *TBB = TI->getOperand(0).getMBB();
+ if (!MBB.isLayoutSuccessor(TBB))
+ BuildMI(MBB, TI, TI->getDebugLoc(), TII.get(WebAssembly::BR))
+ .addMBB(TBB);
+ TI->eraseFromParent();
+ Changed = true;
+ break;
+ }
+ case WebAssembly::CLEANUPRET: {
+ // Replace a cleanupret with a rethrow
+ if (EHInfo->hasThrowUnwindDest(&MBB))
+ BuildMI(MBB, TI, TI->getDebugLoc(), TII.get(WebAssembly::RETHROW))
+ .addMBB(EHInfo->getThrowUnwindDest(&MBB));
+ else
+ BuildMI(MBB, TI, TI->getDebugLoc(),
+ TII.get(WebAssembly::RETHROW_TO_CALLER));
+
+ TI->eraseFromParent();
+ Changed = true;
+ break;
+ }
+ }
+ }
+ return Changed;
+}
+
+// Hoist catch instructions to the beginning of their matching EH pad BBs in
+// case,
+// (1) catch instruction is not the first instruction in EH pad.
+// ehpad:
+// some_other_instruction
+// ...
+// %exn = catch 0
+// (2) catch instruction is in a non-EH pad BB. For example,
+// ehpad:
+// br bb0
+// bb0:
+// %exn = catch 0
+bool WebAssemblyLateEHPrepare::hoistCatches(MachineFunction &MF) {
+ bool Changed = false;
+ SmallVector<MachineInstr *, 16> Catches;
+ for (auto &MBB : MF)
+ for (auto &MI : MBB)
+ if (WebAssembly::isCatch(MI))
+ Catches.push_back(&MI);
+
+ for (auto *Catch : Catches) {
+ MachineBasicBlock *EHPad = GetMatchingEHPad(Catch);
+ assert(EHPad && "No matching EH pad for catch");
+ if (EHPad->begin() == Catch)
+ continue;
+ Changed = true;
+ EHPad->insert(EHPad->begin(), Catch->removeFromParent());
+ }
+ return Changed;
+}
+
+// Add catch_all to beginning of cleanup pads.
+bool WebAssemblyLateEHPrepare::addCatchAlls(MachineFunction &MF) {
+ bool Changed = false;
+ const auto &TII = *MF.getSubtarget<WebAssemblySubtarget>().getInstrInfo();
+
+ for (auto &MBB : MF) {
+ if (!MBB.isEHPad())
+ continue;
+ // This runs after hoistCatches(), so we assume that if there is a catch,
+ // that should be the first instruction in an EH pad.
+ if (!WebAssembly::isCatch(*MBB.begin())) {
+ Changed = true;
+ BuildMI(MBB, MBB.begin(), MBB.begin()->getDebugLoc(),
+ TII.get(WebAssembly::CATCH_ALL));
+ }
+ }
+ return Changed;
+}
+
+// Add a 'rethrow' instruction after __cxa_rethrow() call
+bool WebAssemblyLateEHPrepare::addRethrows(MachineFunction &MF) {
+ bool Changed = false;
+ const auto &TII = *MF.getSubtarget<WebAssemblySubtarget>().getInstrInfo();
+ auto *EHInfo = MF.getWasmEHFuncInfo();
+
+ for (auto &MBB : MF)
+ for (auto &MI : MBB) {
+ // Check if it is a call to __cxa_rethrow()
+ if (!MI.isCall())
+ continue;
+ MachineOperand &CalleeOp = MI.getOperand(0);
+ if (!CalleeOp.isGlobal() ||
+ CalleeOp.getGlobal()->getName() != WebAssembly::CxaRethrowFn)
+ continue;
+
+ // Now we have __cxa_rethrow() call
+ Changed = true;
+ auto InsertPt = std::next(MachineBasicBlock::iterator(MI));
+ while (InsertPt != MBB.end() && InsertPt->isLabel()) // Skip EH_LABELs
+ ++InsertPt;
+ MachineInstr *Rethrow = nullptr;
+ if (EHInfo->hasThrowUnwindDest(&MBB))
+ Rethrow = BuildMI(MBB, InsertPt, MI.getDebugLoc(),
+ TII.get(WebAssembly::RETHROW))
+ .addMBB(EHInfo->getThrowUnwindDest(&MBB));
+ else
+ Rethrow = BuildMI(MBB, InsertPt, MI.getDebugLoc(),
+ TII.get(WebAssembly::RETHROW_TO_CALLER));
+
+ // Becasue __cxa_rethrow does not return, the instruction after the
+ // rethrow should be an unreachable or a branch to another BB that should
+ // eventually lead to an unreachable. Delete it because rethrow itself is
+ // a terminator, and also delete non-EH pad successors if any.
+ MBB.erase(std::next(MachineBasicBlock::iterator(Rethrow)), MBB.end());
+ for (auto *Succ : MBB.successors())
+ if (!Succ->isEHPad())
+ EraseBBAndChildren(Succ);
+ }
+ return Changed;
+}
+
+// Terminate pads are an single-BB EH pad in the form of
+// termpad:
+// %exn = catch 0
+// call @__clang_call_terminate(%exn)
+// unreachable
+// (There can be set_local and get_locals before the call if we didn't run
+// RegStackify)
+// But code transformations can change or add more control flow, so the call to
+// __clang_call_terminate() function may not be in the original EH pad anymore.
+// This ensures every terminate pad is a single BB in the form illustrated
+// above.
+bool WebAssemblyLateEHPrepare::ensureSingleBBTermPads(MachineFunction &MF) {
+ const auto &TII = *MF.getSubtarget<WebAssemblySubtarget>().getInstrInfo();
+
+ // Find calls to __clang_call_terminate()
+ SmallVector<MachineInstr *, 8> ClangCallTerminateCalls;
+ for (auto &MBB : MF)
+ for (auto &MI : MBB)
+ if (MI.isCall()) {
+ const MachineOperand &CalleeOp = MI.getOperand(0);
+ if (CalleeOp.isGlobal() && CalleeOp.getGlobal()->getName() ==
+ WebAssembly::ClangCallTerminateFn)
+ ClangCallTerminateCalls.push_back(&MI);
+ }
+
+ bool Changed = false;
+ for (auto *Call : ClangCallTerminateCalls) {
+ MachineBasicBlock *EHPad = GetMatchingEHPad(Call);
+ assert(EHPad && "No matching EH pad for catch");
+
+ // If it is already the form we want, skip it
+ if (Call->getParent() == EHPad &&
+ Call->getNextNode()->getOpcode() == WebAssembly::UNREACHABLE)
+ continue;
+
+ // In case the __clang_call_terminate() call is not in its matching EH pad,
+ // move the call to the end of EH pad and add an unreachable instruction
+ // after that. Delete all successors and their children if any, because here
+ // the program terminates.
+ Changed = true;
+ MachineInstr *Catch = &*EHPad->begin();
+ // This runs after hoistCatches(), so catch instruction should be at the top
+ assert(WebAssembly::isCatch(*Catch));
+ // Takes the result register of the catch instruction as argument. There may
+ // have been some other set_local/get_locals in between, but at this point
+ // we don't care.
+ Call->getOperand(1).setReg(Catch->getOperand(0).getReg());
+ auto InsertPos = std::next(MachineBasicBlock::iterator(Catch));
+ EHPad->insert(InsertPos, Call->removeFromParent());
+ BuildMI(*EHPad, InsertPos, Call->getDebugLoc(),
+ TII.get(WebAssembly::UNREACHABLE));
+ EHPad->erase(InsertPos, EHPad->end());
+ for (auto *Succ : EHPad->successors())
+ EraseBBAndChildren(Succ);
+ }
+ return Changed;
+}
+
+// In case there are multiple terminate pads, merge them into one for code size.
+// This runs after ensureSingleBBTermPads() and assumes every terminate pad is a
+// single BB.
+// In principle this violates EH scope relationship because it can merge
+// multiple inner EH scopes, each of which is in different outer EH scope. But
+// getEHScopeMembership() function will not be called after this, so it is fine.
+bool WebAssemblyLateEHPrepare::mergeTerminatePads(MachineFunction &MF) {
+ SmallVector<MachineBasicBlock *, 8> TermPads;
+ for (auto &MBB : MF)
+ if (WebAssembly::isCatchTerminatePad(MBB))
+ TermPads.push_back(&MBB);
+ if (TermPads.empty())
+ return false;
+
+ MachineBasicBlock *UniqueTermPad = TermPads.front();
+ for (auto *TermPad :
+ llvm::make_range(std::next(TermPads.begin()), TermPads.end())) {
+ SmallVector<MachineBasicBlock *, 2> Preds(TermPad->pred_begin(),
+ TermPad->pred_end());
+ for (auto *Pred : Preds)
+ Pred->replaceSuccessor(TermPad, UniqueTermPad);
+ TermPad->eraseFromParent();
+ }
+ return true;
+}
+
+// Terminate pads are cleanup pads, so they should start with a 'catch_all'
+// instruction. But in the Itanium model, when we have a C++ exception object,
+// we pass them to __clang_call_terminate function, which calls __cxa_end_catch
+// with the passed exception pointer and then std::terminate. This is the reason
+// that terminate pads are generated with not a catch_all but a catch
+// instruction in clang and earlier llvm passes. Here we append a terminate pad
+// with a catch_all after each existing terminate pad so we can also catch
+// foreign exceptions. For every terminate pad:
+// %exn = catch 0
+// call @__clang_call_terminate(%exn)
+// unreachable
+// We append this BB right after that:
+// catch_all
+// call @std::terminate()
+// unreachable
+bool WebAssemblyLateEHPrepare::addCatchAllTerminatePads(MachineFunction &MF) {
+ const auto &TII = *MF.getSubtarget<WebAssemblySubtarget>().getInstrInfo();
+ SmallVector<MachineBasicBlock *, 8> TermPads;
+ for (auto &MBB : MF)
+ if (WebAssembly::isCatchTerminatePad(MBB))
+ TermPads.push_back(&MBB);
+ if (TermPads.empty())
+ return false;
+
+ Function *StdTerminateFn =
+ MF.getFunction().getParent()->getFunction(WebAssembly::StdTerminateFn);
+ assert(StdTerminateFn && "There is no std::terminate() function");
+ for (auto *CatchTermPad : TermPads) {
+ DebugLoc DL = CatchTermPad->findDebugLoc(CatchTermPad->begin());
+ auto *CatchAllTermPad = MF.CreateMachineBasicBlock();
+ MF.insert(std::next(MachineFunction::iterator(CatchTermPad)),
+ CatchAllTermPad);
+ CatchAllTermPad->setIsEHPad();
+ BuildMI(CatchAllTermPad, DL, TII.get(WebAssembly::CATCH_ALL));
+ BuildMI(CatchAllTermPad, DL, TII.get(WebAssembly::CALL_VOID))
+ .addGlobalAddress(StdTerminateFn);
+ BuildMI(CatchAllTermPad, DL, TII.get(WebAssembly::UNREACHABLE));
+
+ // Actually this CatchAllTermPad (new terminate pad with a catch_all) is not
+ // a successor of an existing terminate pad. CatchAllTermPad should have all
+ // predecessors CatchTermPad has instead. This is a hack to force
+ // CatchAllTermPad be always sorted right after CatchTermPad; the correct
+ // predecessor-successor relationships will be restored in CFGStackify pass.
+ CatchTermPad->addSuccessor(CatchAllTermPad);
+ }
+ return true;
+}
Modified: llvm/trunk/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp?rev=335438&r1=335437&r2=335438&view=diff
==============================================================================
--- llvm/trunk/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp (original)
+++ llvm/trunk/lib/Target/WebAssembly/WebAssemblyTargetMachine.cpp Sun Jun 24 18:07:11 2018
@@ -65,7 +65,7 @@ extern "C" void LLVMInitializeWebAssembl
initializeWebAssemblyRegColoringPass(PR);
initializeWebAssemblyExplicitLocalsPass(PR);
initializeWebAssemblyFixIrreducibleControlFlowPass(PR);
- initializeWebAssemblyExceptionPreparePass(PR);
+ initializeWebAssemblyLateEHPreparePass(PR);
initializeWebAssemblyCFGSortPass(PR);
initializeWebAssemblyCFGStackifyPass(PR);
initializeWebAssemblyLowerBrUnlessPass(PR);
@@ -322,7 +322,7 @@ void WebAssemblyPassConfig::addPreEmitPa
addPass(createWebAssemblyExplicitLocals());
// Do various transformations for exception handling
- addPass(createWebAssemblyExceptionPrepare());
+ addPass(createWebAssemblyLateEHPrepare());
// Sort the blocks of the CFG into topological order, a prerequisite for
// BLOCK and LOOP markers.
Modified: llvm/trunk/test/CodeGen/WebAssembly/exception.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/WebAssembly/exception.ll?rev=335438&r1=335437&r2=335438&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/WebAssembly/exception.ll (original)
+++ llvm/trunk/test/CodeGen/WebAssembly/exception.ll Sun Jun 24 18:07:11 2018
@@ -17,7 +17,7 @@ define void @test_throw() {
ret void
}
-; CHECK-LABEL: test_catch:
+; CHECK-LABEL: test_catch_rethrow:
; CHECK: call foo at FUNCTION
; CHECK: i32.catch $push{{.+}}=, 0
; CHECK-DAG: i32.store __wasm_lpad_context
@@ -26,7 +26,8 @@ define void @test_throw() {
; CHECK: i32.call $push{{.+}}=, __cxa_begin_catch at FUNCTION
; CHECK: call __cxa_end_catch at FUNCTION
; CHECK: call __cxa_rethrow at FUNCTION
-define void @test_catch() personality i8* bitcast (i32 (...)* @__gxx_wasm_personality_v0 to i8*) {
+; CHECK-NEXT: rethrow
+define void @test_catch_rethrow() personality i8* bitcast (i32 (...)* @__gxx_wasm_personality_v0 to i8*) {
entry:
invoke void @foo()
to label %try.cont unwind label %catch.dispatch
@@ -57,9 +58,9 @@ try.cont:
; CHECK-LABEL: test_cleanup:
; CHECK: call foo at FUNCTION
-; CHECK: return
+; CHECK: catch_all
; CHECK: i32.call $push20=, _ZN7CleanupD1Ev at FUNCTION
-; CHECK: rethrow 0
+; CHECK: rethrow
define void @test_cleanup() personality i8* bitcast (i32 (...)* @__gxx_wasm_personality_v0 to i8*) {
entry:
%c = alloca %struct.Cleanup, align 1
@@ -76,8 +77,75 @@ ehcleanup:
cleanupret from %0 unwind to caller
}
+; - Tests multple terminate pads are merged into one
+; - Tests a catch_all terminate pad is created after a catch terminate pad
+
+; CHECK-LABEL: test_terminatepad
+; CHECK: i32.catch
+; CHECK: call __clang_call_terminate at FUNCTION
+; CHECK: unreachable
+; CHECK: catch_all
+; CHECK: call _ZSt9terminatev at FUNCTION
+; CHECK-NOT: call __clang_call_terminate at FUNCTION
+define hidden i32 @test_terminatepad() personality i8* bitcast (i32 (...)* @__gxx_wasm_personality_v0 to i8*) {
+entry:
+ %c = alloca %struct.Cleanup, align 1
+ %c1 = alloca %struct.Cleanup, align 1
+ invoke void @foo()
+ to label %invoke.cont unwind label %ehcleanup
+
+invoke.cont: ; preds = %entry
+ %call = invoke %struct.Cleanup* @_ZN7CleanupD1Ev(%struct.Cleanup* %c1)
+ to label %try.cont unwind label %catch.dispatch
+
+ehcleanup: ; preds = %entry
+ %0 = cleanuppad within none []
+ %call4 = invoke %struct.Cleanup* @_ZN7CleanupD1Ev(%struct.Cleanup* %c1) [ "funclet"(token %0) ]
+ to label %invoke.cont3 unwind label %terminate
+
+invoke.cont3: ; preds = %ehcleanup
+ cleanupret from %0 unwind label %catch.dispatch
+
+catch.dispatch: ; preds = %invoke.cont3, %invoke.cont
+ %1 = catchswitch within none [label %catch.start] unwind label %ehcleanup7
+
+catch.start: ; preds = %catch.dispatch
+ %2 = catchpad within %1 [i8* null]
+ %3 = call i8* @llvm.wasm.get.exception(token %2)
+ %4 = call i32 @llvm.wasm.get.ehselector(token %2)
+ %5 = call i8* @__cxa_begin_catch(i8* %3) [ "funclet"(token %2) ]
+ invoke void @__cxa_end_catch() [ "funclet"(token %2) ]
+ to label %invoke.cont5 unwind label %ehcleanup7
+
+invoke.cont5: ; preds = %catch.start
+ catchret from %2 to label %try.cont
+
+try.cont: ; preds = %invoke.cont5, %invoke.cont
+ %call6 = call %struct.Cleanup* @_ZN7CleanupD1Ev(%struct.Cleanup* %c)
+ ret i32 0
+
+ehcleanup7: ; preds = %catch.start, %catch.dispatch
+ %6 = cleanuppad within none []
+ %call9 = invoke %struct.Cleanup* @_ZN7CleanupD1Ev(%struct.Cleanup* %c) [ "funclet"(token %6) ]
+ to label %invoke.cont8 unwind label %terminate10
+
+invoke.cont8: ; preds = %ehcleanup7
+ cleanupret from %6 unwind to caller
+
+terminate: ; preds = %ehcleanup
+ %7 = cleanuppad within %0 []
+ %8 = call i8* @llvm.wasm.get.exception(token %7)
+ call void @__clang_call_terminate(i8* %8) [ "funclet"(token %7) ]
+ unreachable
+
+terminate10: ; preds = %ehcleanup7
+ %9 = cleanuppad within %6 []
+ %10 = call i8* @llvm.wasm.get.exception(token %9)
+ call void @__clang_call_terminate(i8* %10) [ "funclet"(token %9) ]
+ unreachable
+}
+
declare void @foo()
-declare void @func(i32)
declare i32 @__gxx_wasm_personality_v0(...)
declare i8* @llvm.wasm.get.exception(token)
declare i32 @llvm.wasm.get.ehselector(token)
@@ -86,4 +154,5 @@ declare i8* @__cxa_begin_catch(i8*)
declare void @__cxa_end_catch()
declare void @__cxa_rethrow()
declare void @__clang_call_terminate(i8*)
+declare void @_ZSt9terminatev()
declare %struct.Cleanup* @_ZN7CleanupD1Ev(%struct.Cleanup* returned)
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