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| author | Craig Topper <craig.topper@gmail.com> | 2012-09-13 05:45:42 +0000 |
|---|---|---|
| committer | Craig Topper <craig.topper@gmail.com> | 2012-09-13 05:45:42 +0000 |
| commit | 76b29b518dad5e719077a1066e242fa91f777a7c (patch) | |
| tree | 4d4219f3a5859b42b605958219d94dfd631f3e5f /lib/Target/X86/Disassembler | |
| parent | 7639f98c5fc903339bf50e574aee999d54340cdf (diff) | |
| download | external_llvm-76b29b518dad5e719077a1066e242fa91f777a7c.zip external_llvm-76b29b518dad5e719077a1066e242fa91f777a7c.tar.gz external_llvm-76b29b518dad5e719077a1066e242fa91f777a7c.tar.bz2 | |
Add a new compression type to ModRM table that detects when the memory modRM byte represent 8 instructions and the reg modRM byte represents up to 64 instructions. Reduces modRM table from 43k entreis to 25k entries. Based on a patch from Manman Ren.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163774 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Target/X86/Disassembler')
| -rw-r--r-- | lib/Target/X86/Disassembler/X86DisassemblerDecoder.c | 4 | ||||
| -rw-r--r-- | lib/Target/X86/Disassembler/X86DisassemblerDecoderCommon.h | 5 |
2 files changed, 9 insertions, 0 deletions
diff --git a/lib/Target/X86/Disassembler/X86DisassemblerDecoder.c b/lib/Target/X86/Disassembler/X86DisassemblerDecoder.c index af444d1..b24f517 100644 --- a/lib/Target/X86/Disassembler/X86DisassemblerDecoder.c +++ b/lib/Target/X86/Disassembler/X86DisassemblerDecoder.c @@ -138,6 +138,10 @@ static InstrUID decode(OpcodeType type, if (modFromModRM(modRM) == 0x3) return modRMTable[dec->instructionIDs+((modRM & 0x38) >> 3)+8]; return modRMTable[dec->instructionIDs+((modRM & 0x38) >> 3)]; + case MODRM_SPLITMISC: + if (modFromModRM(modRM) == 0x3) + return modRMTable[dec->instructionIDs+(modRM & 0x3f)+8]; + return modRMTable[dec->instructionIDs+((modRM & 0x38) >> 3)]; case MODRM_FULL: return modRMTable[dec->instructionIDs+modRM]; } diff --git a/lib/Target/X86/Disassembler/X86DisassemblerDecoderCommon.h b/lib/Target/X86/Disassembler/X86DisassemblerDecoderCommon.h index b0a0e1e..23dfe4b 100644 --- a/lib/Target/X86/Disassembler/X86DisassemblerDecoderCommon.h +++ b/lib/Target/X86/Disassembler/X86DisassemblerDecoderCommon.h @@ -160,6 +160,10 @@ typedef uint16_t InstrUID; * MODRM_SPLITRM - If the ModR/M byte is between 0x00 and 0xbf, the opcode * corresponds to one instruction; otherwise, it corresponds to * a different instruction. + * MODRM_SPLITMISC- If the ModR/M byte is between 0x00 and 0xbf, ModR/M byte + * divided by 8 is used to select instruction; otherwise, each + * value of the ModR/M byte could correspond to a different + * instruction. * MODRM_SPLITREG - ModR/M byte divided by 8 is used to select instruction. This corresponds to instructions that use reg field as opcode * MODRM_FULL - Potentially, each value of the ModR/M byte could correspond @@ -169,6 +173,7 @@ typedef uint16_t InstrUID; #define MODRMTYPES \ ENUM_ENTRY(MODRM_ONEENTRY) \ ENUM_ENTRY(MODRM_SPLITRM) \ + ENUM_ENTRY(MODRM_SPLITMISC) \ ENUM_ENTRY(MODRM_SPLITREG) \ ENUM_ENTRY(MODRM_FULL) |