1 //===-- WebAssemblyUtilities - WebAssembly Utility Functions ---*- C++ -*-====//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 ///
9 /// \file
10 /// This file contains the declaration of the WebAssembly-specific
11 /// utility functions.
12 ///
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_LIB_TARGET_WEBASSEMBLY_UTILS_WEBASSEMBLYUTILITIES_H
16 #define LLVM_LIB_TARGET_WEBASSEMBLY_UTILS_WEBASSEMBLYUTILITIES_H
17 
18 #include "llvm/Support/CommandLine.h"
19 
20 namespace llvm {
21 
22 class MachineBasicBlock;
23 class MachineInstr;
24 class MachineOperand;
25 class MCContext;
26 class MCSymbolWasm;
27 class TargetRegisterClass;
28 class WebAssemblyFunctionInfo;
29 class WebAssemblySubtarget;
30 
31 namespace WebAssembly {
32 
33 bool isChild(const MachineInstr &MI, const WebAssemblyFunctionInfo &MFI);
34 bool mayThrow(const MachineInstr &MI);
35 
36 // Exception handling / setjmp-longjmp handling command-line options
37 extern cl::opt<bool> WasmEnableEmEH;   // asm.js-style EH
38 extern cl::opt<bool> WasmEnableEmSjLj; // asm.js-style SjLJ
39 extern cl::opt<bool> WasmEnableEH;     // EH using Wasm EH instructions
40 extern cl::opt<bool> WasmEnableSjLj;   // SjLj using Wasm EH instructions
41 
42 // Exception-related function names
43 extern const char *const ClangCallTerminateFn;
44 extern const char *const CxaBeginCatchFn;
45 extern const char *const CxaRethrowFn;
46 extern const char *const StdTerminateFn;
47 extern const char *const PersonalityWrapperFn;
48 
49 /// Returns the operand number of a callee, assuming the argument is a call
50 /// instruction.
51 const MachineOperand &getCalleeOp(const MachineInstr &MI);
52 
53 /// Returns the __indirect_function_table, for use in call_indirect and in
54 /// function bitcasts.
55 MCSymbolWasm *
56 getOrCreateFunctionTableSymbol(MCContext &Ctx,
57                                const WebAssemblySubtarget *Subtarget);
58 
59 /// Returns the __funcref_call_table, for use in funcref calls when lowered to
60 /// table.set + call_indirect.
61 MCSymbolWasm *
62 getOrCreateFuncrefCallTableSymbol(MCContext &Ctx,
63                                   const WebAssemblySubtarget *Subtarget);
64 
65 /// Find a catch instruction from an EH pad. Returns null if no catch
66 /// instruction found or the catch is in an invalid location.
67 MachineInstr *findCatch(MachineBasicBlock *EHPad);
68 
69 /// Returns the appropriate copy opcode for the given register class.
70 unsigned getCopyOpcodeForRegClass(const TargetRegisterClass *RC);
71 
72 } // end namespace WebAssembly
73 
74 } // end namespace llvm
75 
76 #endif
77