CoreDisTools: Remove Prefix Decode Verification.

dotnet / llilc

This repo contains LLILC, an LLVM based compiler for .NET Core. It includes a set of cross-platform .NET code generation tools that enables compilation of MSIL byte code to LLVM supported platforms.

MIT License

1.52k stars 153 forks source link

CoreDisTools: Remove Prefix Decode Verification. #1055

Closed swaroop-sridhar closed 8 years ago

swaroop-sridhar commented 8 years ago

Remove VerifyPrefixDeocde() in the Core-Disassembler, because: 1) It doesn't serve any purpose -- CorDisasm::disasmInstruction() uses machine opcodes (and not LLVM opcodes) to decide when to continue disassembly past a prefix instruction 2) LLVM decodes different sets of prefixes as independent instructions on X86 and AMD64 -- so this leads to unnecessary overhead in maintaining the X86Prefix::IsLLVMInstruction state.

swaroop-sridhar commented 8 years ago

@AndyAyersMS please review

swaroop-sridhar commented 8 years ago

CC: @LLITCHEV

AndyAyersMS commented 8 years ago

LGTM