diff options
| author | vvvv <[email protected]> | 2024-02-06 20:01:22 +0300 |
|---|---|---|
| committer | vvvv <[email protected]> | 2024-02-06 20:22:16 +0300 |
| commit | 0203b7a9a40828bb2bd4c32029b79ff0ea3d1f8f (patch) | |
| tree | e630d0d5bd0bd29fc8c2d2842ed2cfde781b993a /contrib/libs/llvm16/lib/Target/WebAssembly/Utils/WebAssemblyUtilities.cpp | |
| parent | ba27db76d99d12a4f1c06960b5449423218614c4 (diff) | |
llvm16 targets
Diffstat (limited to 'contrib/libs/llvm16/lib/Target/WebAssembly/Utils/WebAssemblyUtilities.cpp')
| -rw-r--r-- | contrib/libs/llvm16/lib/Target/WebAssembly/Utils/WebAssemblyUtilities.cpp | 203 |
1 files changed, 203 insertions, 0 deletions
diff --git a/contrib/libs/llvm16/lib/Target/WebAssembly/Utils/WebAssemblyUtilities.cpp b/contrib/libs/llvm16/lib/Target/WebAssembly/Utils/WebAssemblyUtilities.cpp new file mode 100644 index 00000000000..a1e0db69239 --- /dev/null +++ b/contrib/libs/llvm16/lib/Target/WebAssembly/Utils/WebAssemblyUtilities.cpp @@ -0,0 +1,203 @@ +//===-- WebAssemblyUtilities.cpp - WebAssembly Utility Functions ----------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +/// +/// \file +/// This file implements several utility functions for WebAssembly. +/// +//===----------------------------------------------------------------------===// + +#include "WebAssemblyUtilities.h" +#include "WebAssemblyMachineFunctionInfo.h" +#include "llvm/CodeGen/MachineInstr.h" +#include "llvm/CodeGen/MachineLoopInfo.h" +#include "llvm/MC/MCContext.h" +using namespace llvm; + +// Exception handling & setjmp-longjmp handling related options. These are +// defined here to be shared between WebAssembly and its subdirectories. + +// Emscripten's asm.js-style exception handling +cl::opt<bool> WebAssembly::WasmEnableEmEH( + "enable-emscripten-cxx-exceptions", + cl::desc("WebAssembly Emscripten-style exception handling"), + cl::init(false)); +// Emscripten's asm.js-style setjmp/longjmp handling +cl::opt<bool> WebAssembly::WasmEnableEmSjLj( + "enable-emscripten-sjlj", + cl::desc("WebAssembly Emscripten-style setjmp/longjmp handling"), + cl::init(false)); +// Exception handling using wasm EH instructions +cl::opt<bool> + WebAssembly::WasmEnableEH("wasm-enable-eh", + cl::desc("WebAssembly exception handling"), + cl::init(false)); +// setjmp/longjmp handling using wasm EH instrutions +cl::opt<bool> + WebAssembly::WasmEnableSjLj("wasm-enable-sjlj", + cl::desc("WebAssembly setjmp/longjmp handling"), + cl::init(false)); + +// Function names in libc++abi and libunwind +const char *const WebAssembly::CxaBeginCatchFn = "__cxa_begin_catch"; +const char *const WebAssembly::CxaRethrowFn = "__cxa_rethrow"; +const char *const WebAssembly::StdTerminateFn = "_ZSt9terminatev"; +const char *const WebAssembly::PersonalityWrapperFn = + "_Unwind_Wasm_CallPersonality"; + +/// Test whether MI is a child of some other node in an expression tree. +bool WebAssembly::isChild(const MachineInstr &MI, + const WebAssemblyFunctionInfo &MFI) { + if (MI.getNumOperands() == 0) + return false; + const MachineOperand &MO = MI.getOperand(0); + if (!MO.isReg() || MO.isImplicit() || !MO.isDef()) + return false; + Register Reg = MO.getReg(); + return Reg.isVirtual() && MFI.isVRegStackified(Reg); +} + +bool WebAssembly::mayThrow(const MachineInstr &MI) { + switch (MI.getOpcode()) { + case WebAssembly::THROW: + case WebAssembly::THROW_S: + case WebAssembly::RETHROW: + case WebAssembly::RETHROW_S: + return true; + } + if (isCallIndirect(MI.getOpcode())) + return true; + if (!MI.isCall()) + return false; + + const MachineOperand &MO = getCalleeOp(MI); + assert(MO.isGlobal() || MO.isSymbol()); + + if (MO.isSymbol()) { + // Some intrinsics are lowered to calls to external symbols, which are then + // lowered to calls to library functions. Most of libcalls don't throw, but + // we only list some of them here now. + // TODO Consider adding 'nounwind' info in TargetLowering::CallLoweringInfo + // instead for more accurate info. + const char *Name = MO.getSymbolName(); + if (strcmp(Name, "memcpy") == 0 || strcmp(Name, "memmove") == 0 || + strcmp(Name, "memset") == 0) + return false; + return true; + } + + const auto *F = dyn_cast<Function>(MO.getGlobal()); + if (!F) + return true; + if (F->doesNotThrow()) + return false; + // These functions never throw + if (F->getName() == CxaBeginCatchFn || F->getName() == PersonalityWrapperFn || + F->getName() == StdTerminateFn) + return false; + + // TODO Can we exclude call instructions that are marked as 'nounwind' in the + // original LLVm IR? (Even when the callee may throw) + return true; +} + +const MachineOperand &WebAssembly::getCalleeOp(const MachineInstr &MI) { + switch (MI.getOpcode()) { + case WebAssembly::CALL: + case WebAssembly::CALL_S: + case WebAssembly::RET_CALL: + case WebAssembly::RET_CALL_S: + return MI.getOperand(MI.getNumExplicitDefs()); + case WebAssembly::CALL_INDIRECT: + case WebAssembly::CALL_INDIRECT_S: + case WebAssembly::RET_CALL_INDIRECT: + case WebAssembly::RET_CALL_INDIRECT_S: + return MI.getOperand(MI.getNumExplicitOperands() - 1); + default: + llvm_unreachable("Not a call instruction"); + } +} + +MCSymbolWasm *WebAssembly::getOrCreateFunctionTableSymbol( + MCContext &Ctx, const WebAssemblySubtarget *Subtarget) { + StringRef Name = "__indirect_function_table"; + MCSymbolWasm *Sym = cast_or_null<MCSymbolWasm>(Ctx.lookupSymbol(Name)); + if (Sym) { + if (!Sym->isFunctionTable()) + Ctx.reportError(SMLoc(), "symbol is not a wasm funcref table"); + } else { + Sym = cast<MCSymbolWasm>(Ctx.getOrCreateSymbol(Name)); + Sym->setFunctionTable(); + // The default function table is synthesized by the linker. + Sym->setUndefined(); + } + // MVP object files can't have symtab entries for tables. + if (!(Subtarget && Subtarget->hasReferenceTypes())) + Sym->setOmitFromLinkingSection(); + return Sym; +} + +MCSymbolWasm *WebAssembly::getOrCreateFuncrefCallTableSymbol( + MCContext &Ctx, const WebAssemblySubtarget *Subtarget) { + StringRef Name = "__funcref_call_table"; + MCSymbolWasm *Sym = cast_or_null<MCSymbolWasm>(Ctx.lookupSymbol(Name)); + if (Sym) { + if (!Sym->isFunctionTable()) + Ctx.reportError(SMLoc(), "symbol is not a wasm funcref table"); + } else { + Sym = cast<MCSymbolWasm>(Ctx.getOrCreateSymbol(Name)); + + // Setting Weak ensure only one table is left after linking when multiple + // modules define the table. + Sym->setWeak(true); + + wasm::WasmLimits Limits = {0, 1, 1}; + wasm::WasmTableType TableType = {wasm::WASM_TYPE_FUNCREF, Limits}; + Sym->setType(wasm::WASM_SYMBOL_TYPE_TABLE); + Sym->setTableType(TableType); + } + // MVP object files can't have symtab entries for tables. + if (!(Subtarget && Subtarget->hasReferenceTypes())) + Sym->setOmitFromLinkingSection(); + return Sym; +} + +// Find a catch instruction from an EH pad. +MachineInstr *WebAssembly::findCatch(MachineBasicBlock *EHPad) { + assert(EHPad->isEHPad()); + auto Pos = EHPad->begin(); + // Skip any label or debug instructions. Also skip 'end' marker instructions + // that may exist after marker placement in CFGStackify. + while (Pos != EHPad->end() && + (Pos->isLabel() || Pos->isDebugInstr() || isMarker(Pos->getOpcode()))) + Pos++; + if (Pos != EHPad->end() && WebAssembly::isCatch(Pos->getOpcode())) + return &*Pos; + return nullptr; +} + +unsigned WebAssembly::getCopyOpcodeForRegClass(const TargetRegisterClass *RC) { + assert(RC != nullptr); + switch (RC->getID()) { + case WebAssembly::I32RegClassID: + return WebAssembly::COPY_I32; + case WebAssembly::I64RegClassID: + return WebAssembly::COPY_I64; + case WebAssembly::F32RegClassID: + return WebAssembly::COPY_F32; + case WebAssembly::F64RegClassID: + return WebAssembly::COPY_F64; + case WebAssembly::V128RegClassID: + return WebAssembly::COPY_V128; + case WebAssembly::FUNCREFRegClassID: + return WebAssembly::COPY_FUNCREF; + case WebAssembly::EXTERNREFRegClassID: + return WebAssembly::COPY_EXTERNREF; + default: + llvm_unreachable("Unexpected register class"); + } +} |
