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| author | Jan Beulich <jbeulich@suse.com> | 2024-06-21 14:40:44 +0200 |
|---|---|---|
| committer | Jan Beulich <jbeulich@suse.com> | 2024-06-21 14:40:44 +0200 |
| commit | f4a966a91d23ae78000d577665502edff7274fd9 (patch) | |
| tree | 39003f6ed23e61899ec60657a8af6492d1f363d7 /gas/config/tc-i386.c | |
| parent | fa2c4239f1ab70b198f6d404f727d0d744221595 (diff) | |
| download | binutils-f4a966a91d23ae78000d577665502edff7274fd9.zip binutils-f4a966a91d23ae78000d577665502edff7274fd9.tar.gz binutils-f4a966a91d23ae78000d577665502edff7274fd9.tar.bz2 | |
x86: optimize {,V}PEXTR{D,Q} with immediate of 0
Such are equivalent to simple moves, which are up to 3 bytes shorter to
encode (and perhaps also cheaper to execute).
Diffstat (limited to 'gas/config/tc-i386.c')
| -rw-r--r-- | gas/config/tc-i386.c | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/gas/config/tc-i386.c b/gas/config/tc-i386.c index ae1ef56..ab52692 100644 --- a/gas/config/tc-i386.c +++ b/gas/config/tc-i386.c @@ -5287,6 +5287,44 @@ optimize_encoding (void) swap_2_operands (1, 2); } + else if (i.tm.base_opcode == 0x16 + && i.tm.opcode_space == SPACE_0F3A + && i.op[0].imms->X_op == O_constant + && i.op[0].imms->X_add_number == 0) + { + /* Optimize: -O: + pextrd $0, %xmmN, ... -> movd %xmmN, ... + pextrq $0, %xmmN, ... -> movq %xmmN, ... + vpextrd $0, %xmmN, ... -> vmovd %xmmN, ... + vpextrq $0, %xmmN, ... -> vmovq %xmmN, ... + */ + i.tm.opcode_space = SPACE_0F; + if (!i.mem_operands + || i.tm.opcode_modifier.evex + || (i.tm.opcode_modifier.vexw != VEXW1 + && i.tm.opcode_modifier.size != SIZE64)) + i.tm.base_opcode = 0x7e; + else + { + i.tm.base_opcode = 0xd6; + i.tm.opcode_modifier.size = 0; + i.tm.opcode_modifier.vexw + = i.tm.opcode_modifier.sse2avx ? VEXW0 : VEXWIG; + } + + i.op[0].regs = i.op[1].regs; + i.types[0] = i.types[1]; + i.flags[0] = i.flags[1]; + i.tm.operand_types[0] = i.tm.operand_types[1]; + + i.op[1].regs = i.op[2].regs; + i.types[1] = i.types[2]; + i.flags[1] = i.flags[2]; + i.tm.operand_types[1] = i.tm.operand_types[2]; + + i.operands = 2; + i.imm_operands = 0; + } } static void |