Index: llvm/trunk/lib/Target/WebAssembly/WebAssemblyCFGSort.cpp =================================================================== --- llvm/trunk/lib/Target/WebAssembly/WebAssemblyCFGSort.cpp +++ llvm/trunk/lib/Target/WebAssembly/WebAssemblyCFGSort.cpp @@ -34,6 +34,14 @@ #define DEBUG_TYPE "wasm-cfg-sort" +// Option to disable EH pad first sorting. Only for testing unwind destination +// mismatches in CFGStackify. +static cl::opt WasmDisableEHPadSort( + "wasm-disable-ehpad-sort", cl::ReallyHidden, + cl::desc( + "WebAssembly: Disable EH pad-first sort order. Testing purpose only."), + cl::init(false)); + namespace { // Wrapper for loops and exceptions @@ -187,10 +195,12 @@ struct CompareBlockNumbers { bool operator()(const MachineBasicBlock *A, const MachineBasicBlock *B) const { - if (A->isEHPad() && !B->isEHPad()) - return false; - if (!A->isEHPad() && B->isEHPad()) - return true; + if (!WasmDisableEHPadSort) { + if (A->isEHPad() && !B->isEHPad()) + return false; + if (!A->isEHPad() && B->isEHPad()) + return true; + } return A->getNumber() > B->getNumber(); } @@ -199,11 +209,12 @@ struct CompareBlockNumbersBackwards { bool operator()(const MachineBasicBlock *A, const MachineBasicBlock *B) const { - // We give a higher priority to an EH pad - if (A->isEHPad() && !B->isEHPad()) - return false; - if (!A->isEHPad() && B->isEHPad()) - return true; + if (!WasmDisableEHPadSort) { + if (A->isEHPad() && !B->isEHPad()) + return false; + if (!A->isEHPad() && B->isEHPad()) + return true; + } return A->getNumber() < B->getNumber(); } Index: llvm/trunk/lib/Target/WebAssembly/WebAssemblyInstrInfo.cpp =================================================================== --- llvm/trunk/lib/Target/WebAssembly/WebAssemblyInstrInfo.cpp +++ llvm/trunk/lib/Target/WebAssembly/WebAssemblyInstrInfo.cpp @@ -101,6 +101,13 @@ MachineBasicBlock *&FBB, SmallVectorImpl &Cond, bool /*AllowModify*/) const { + const auto &MFI = *MBB.getParent()->getInfo(); + // WebAssembly has control flow that doesn't have explicit branches or direct + // fallthrough (e.g. try/catch), which can't be modeled by analyzeBranch. It + // is created after CFGStackify. + if (MFI.isCFGStackified()) + return true; + bool HaveCond = false; for (MachineInstr &MI : MBB.terminators()) { switch (MI.getOpcode()) { @@ -110,9 +117,6 @@ case WebAssembly::BR_IF: if (HaveCond) return true; - // If we're running after CFGStackify, we can't optimize further. - if (!MI.getOperand(0).isMBB()) - return true; Cond.push_back(MachineOperand::CreateImm(true)); Cond.push_back(MI.getOperand(1)); TBB = MI.getOperand(0).getMBB(); @@ -121,18 +125,12 @@ case WebAssembly::BR_UNLESS: if (HaveCond) return true; - // If we're running after CFGStackify, we can't optimize further. - if (!MI.getOperand(0).isMBB()) - return true; Cond.push_back(MachineOperand::CreateImm(false)); Cond.push_back(MI.getOperand(1)); TBB = MI.getOperand(0).getMBB(); HaveCond = true; break; case WebAssembly::BR: - // If we're running after CFGStackify, we can't optimize further. - if (!MI.getOperand(0).isMBB()) - return true; if (!HaveCond) TBB = MI.getOperand(0).getMBB(); else @@ -141,9 +139,6 @@ case WebAssembly::BR_ON_EXN: if (HaveCond) return true; - // If we're running after CFGStackify, we can't optimize further. - if (!MI.getOperand(0).isMBB()) - return true; Cond.push_back(MachineOperand::CreateImm(true)); Cond.push_back(MI.getOperand(2)); TBB = MI.getOperand(0).getMBB(); Index: llvm/trunk/test/CodeGen/WebAssembly/cfg-stackify-eh.ll =================================================================== --- llvm/trunk/test/CodeGen/WebAssembly/cfg-stackify-eh.ll +++ llvm/trunk/test/CodeGen/WebAssembly/cfg-stackify-eh.ll @@ -1,5 +1,6 @@ ; RUN: llc < %s -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -wasm-keep-registers -disable-block-placement -verify-machineinstrs -fast-isel=false -machine-sink-split-probability-threshold=0 -cgp-freq-ratio-to-skip-merge=1000 -exception-model=wasm -mattr=+exception-handling | FileCheck %s ; RUN: llc < %s -O0 -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -wasm-keep-registers -verify-machineinstrs -exception-model=wasm -mattr=+exception-handling | FileCheck %s --check-prefix=NOOPT +; RUN: llc < %s -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -wasm-keep-registers -disable-block-placement -verify-machineinstrs -fast-isel=false -machine-sink-split-probability-threshold=0 -cgp-freq-ratio-to-skip-merge=1000 -exception-model=wasm -mattr=+exception-handling -wasm-disable-ehpad-sort target datalayout = "e-m:e-p:32:32-i64:64-n32:64-S128" target triple = "wasm32-unknown-unknown"