[PATCH, x86] Generate vector -1 with pcmpeq

[Evan Cheng <evan dot cheng at apple dot com>]

Hi,

This patch allows vector constant -1 be generated with a pcmpeq  
instruction instead of a load.

For example:

__m128i set1_32bit() {
        return _mm_set1_epi32(-1);
}

    .size    set1_16bit, .-set1_16bit
.globl set1_32bit
    .type    set1_32bit, @function
set1_32bit:
    pushl    %ebp
    movl    %esp, %ebp
    pcmpeqw    %xmm0, %xmm0
    popl    %ebp
    ret


2005-10-28  Evan Cheng  <evan.cheng@apple.com>

    * config/i386/i386-protos.h (ix86_const_vector_all_ones_operand)
    Declare
    * config/i386/i386.c (ix86_const_vector_all_ones_operand) New  
function.
    (standard_sse_constant_p) Return true for constant 0 or vector  
constant
    all one's.
    (standard_sse_constant_opcode) New function to return the opcode
    associated with standard_sse_constant_p.
    (ix86_expand_vector_move) Also check for vector constant all one's.
    * config/i386/predicates.md (vector_all_ones_operand) True if  
vector
    constant all one's.
    (vector_move_operand) True if vector_all_ones_operand is true.
    * config/i386/sse.md (*mov<mode>_internal) Use
    standard_sse_constant_opcode.
    (*movv4sf_internal) Use standard_sse_constant_opcode.
    (*movv2df_internal) Use standard_sse_constant_opcode.
    (*vec_setv4sf_0) Added condition ! 
ix86_const_vector_all_ones_operand.
    (sse2_loadlpd) Added condition !ix86_const_vector_all_ones_operand.
    (*vec_concatv2df) Added condition ! 
ix86_const_vector_all_ones_operand.
    (*vec_concatv2di) Added condition ! 
ix86_const_vector_all_ones_operand.

Attachment: patch.fsf.4283414.txt
Description: Text document

Evan