i386: Use existing temporary register in rounding functions

It is possible to avoid the call to force_reg and use existing
temporary register in ix86_expand_trunc, ix86_expand_round and
ix86_expand_rounddf_32 expanders.

2020-12-28  Uroš Bizjak  <ubizjak@gmail.com>

gcc/
	* config/i386/i386-expand.c (ix86_expand_trunc): Use
	existing temporary register to avoid a call to force_reg.
This commit is contained in:
Uros Bizjak 2020-12-28 16:52:45 +01:00
parent 12ae2bc708
commit 97d3ddcfc9

View File

@ -16513,13 +16513,15 @@ ix86_expand_trunc (rtx operand0, rtx operand1)
/* if (!isless (xa, TWO52)) goto label; */
label = ix86_expand_sse_compare_and_jump (UNLE, TWO52, xa, false);
/* x = (double)(long)x */
/* xa = (double)(long)x */
xi = gen_reg_rtx (mode == DFmode ? DImode : SImode);
expand_fix (xi, res, 0);
expand_float (res, xi, 0);
expand_float (xa, xi, 0);
if (HONOR_SIGNED_ZEROS (mode))
ix86_sse_copysign_to_positive (res, res, force_reg (mode, operand1), mask);
ix86_sse_copysign_to_positive (xa, xa, res, mask);
emit_move_insn (res, xa);
emit_label (label);
LABEL_NUSES (label) = 1;
@ -16629,7 +16631,7 @@ ix86_expand_round (rtx operand0, rtx operand1)
expand_float (xa, xi, 0);
/* res = copysign (xa, operand1) */
ix86_sse_copysign_to_positive (res, xa, force_reg (mode, operand1), mask);
ix86_sse_copysign_to_positive (res, xa, res, mask);
emit_label (label);
LABEL_NUSES (label) = 1;
@ -16700,7 +16702,7 @@ ix86_expand_rounddf_32 (rtx operand0, rtx operand1)
xa2 = expand_simple_binop (mode, PLUS, xa2, tmp, NULL_RTX, 0, OPTAB_DIRECT);
/* res = copysign (xa2, operand1) */
ix86_sse_copysign_to_positive (res, xa2, force_reg (mode, operand1), mask);
ix86_sse_copysign_to_positive (res, xa2, res, mask);
emit_label (label);
LABEL_NUSES (label) = 1;