From: Uros Bizjak Date: Tue, 29 Dec 2020 07:43:38 +0000 (+0100) Subject: i386: Rounding functions TLC X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=d2754fbb65dd3b81487769317bae4e9a8cee01c9;p=gcc.git i386: Rounding functions TLC Use copy_to_reg where appropriate, use int_mode_for_mode and fix comment indentation. 2020-12-29 Uroš Bizjak gcc/ * config/i386/i386-expand.c (ix86_gen_TWO52): Use REAL_MODE_FORMAT to determine number of mantissa bits. Use real_2expN instead of real_ldexp. (ix86_expand_rint): Use copy_to_reg. (ix86_expand_floorceildf_32): Ditto. (ix86_expand_truncdf_32): Ditto. (ix86_expand_rounddf_32): Ditto. (ix86_expand_floorceil): Use copy_to_reg and int_mode_for_mode. (ix86_expand_trunc): Ditto. (ix86_expand_round): Ditto. --- diff --git a/gcc/config/i386/i386-expand.c b/gcc/config/i386/i386-expand.c index 5c48cded954..6e08fd32726 100644 --- a/gcc/config/i386/i386-expand.c +++ b/gcc/config/i386/i386-expand.c @@ -16214,8 +16214,8 @@ void ix86_expand_lround (rtx op0, rtx op1) { /* C code for the stuff we're doing below: - tmp = op1 + copysign (nextafter (0.5, 0.0), op1) - return (long)tmp; + tmp = op1 + copysign (nextafter (0.5, 0.0), op1) + return (long)tmp; */ machine_mode mode = GET_MODE (op1); const struct real_format *fmt; @@ -16246,8 +16246,8 @@ ix86_expand_lfloorceil (rtx op0, rtx op1, bool do_floor) { /* C code for the stuff we're doing below (for do_floor): xi = (long)op1; - xi -= (double)xi > op1 ? 1 : 0; - return xi; + xi -= (double)xi > op1 ? 1 : 0; + return xi; */ machine_mode fmode = GET_MODE (op1); machine_mode imode = GET_MODE (op0); @@ -16281,10 +16281,12 @@ ix86_expand_lfloorceil (rtx op0, rtx op1, bool do_floor) static rtx ix86_gen_TWO52 (machine_mode mode) { + const struct real_format *fmt; REAL_VALUE_TYPE TWO52r; rtx TWO52; - real_ldexp (&TWO52r, &dconst1, mode == DFmode ? 52 : 23); + fmt = REAL_MODE_FORMAT (mode); + real_2expN (&TWO52r, fmt->p - 1, mode); TWO52 = const_double_from_real_value (TWO52r, mode); TWO52 = force_reg (mode, TWO52); @@ -16298,29 +16300,31 @@ ix86_expand_rint (rtx operand0, rtx operand1) { /* C code for the stuff we're doing below: xa = fabs (operand1); - if (!isless (xa, 2**52)) + if (!isless (xa, 2**52)) return operand1; - two52 = 2**52; - if (flag_rounding_math) + two52 = 2**52; + if (flag_rounding_math) { two52 = copysign (two52, operand1); xa = operand1; } - xa = xa + two52 - two52; - return copysign (xa, operand1); + xa = xa + two52 - two52; + return copysign (xa, operand1); */ machine_mode mode = GET_MODE (operand0); rtx res, xa, TWO52, mask; rtx_code_label *label; - res = gen_reg_rtx (mode); - emit_move_insn (res, operand1); + TWO52 = ix86_gen_TWO52 (mode); + + /* Temporary for holding the result, initialized to the input + operand to ease control flow. */ + res = copy_to_reg (operand1); /* xa = abs (operand1) */ xa = ix86_expand_sse_fabs (res, &mask); /* if (!isless (xa, TWO52)) goto label; */ - TWO52 = ix86_gen_TWO52 (mode); label = ix86_expand_sse_compare_and_jump (UNLE, TWO52, xa, false); if (flag_rounding_math) @@ -16351,8 +16355,8 @@ ix86_expand_floorceil (rtx operand0, rtx operand1, bool do_floor) { /* C code for the stuff we expand below. double xa = fabs (x), x2; - if (!isless (xa, TWO52)) - return x; + if (!isless (xa, TWO52)) + return x; x2 = (double)(long)x; Compensate. Floor: @@ -16374,8 +16378,7 @@ ix86_expand_floorceil (rtx operand0, rtx operand1, bool do_floor) /* Temporary for holding the result, initialized to the input operand to ease control flow. */ - res = gen_reg_rtx (mode); - emit_move_insn (res, operand1); + res = copy_to_reg (operand1); /* xa = abs (operand1) */ xa = ix86_expand_sse_fabs (res, &mask); @@ -16384,7 +16387,7 @@ ix86_expand_floorceil (rtx operand0, rtx operand1, bool do_floor) label = ix86_expand_sse_compare_and_jump (UNLE, TWO52, xa, false); /* xa = (double)(long)x */ - xi = gen_reg_rtx (mode == DFmode ? DImode : SImode); + xi = gen_reg_rtx (int_mode_for_mode (mode).require ()); expand_fix (xi, res, 0); expand_float (xa, xi, 0); @@ -16419,18 +16422,18 @@ void ix86_expand_floorceildf_32 (rtx operand0, rtx operand1, bool do_floor) { /* C code for the stuff we expand below. - double xa = fabs (x), x2; - if (!isless (xa, TWO52)) - return x; - xa = xa + TWO52 - TWO52; - x2 = copysign (xa, x); + double xa = fabs (x), x2; + if (!isless (xa, TWO52)) + return x; + xa = xa + TWO52 - TWO52; + x2 = copysign (xa, x); Compensate. Floor: - if (x2 > x) - x2 -= 1; + if (x2 > x) + x2 -= 1; Compensate. Ceil: - if (x2 < x) - x2 += 1; + if (x2 < x) + x2 += 1; if (HONOR_SIGNED_ZEROS (mode)) x2 = copysign (x2, x); @@ -16444,8 +16447,7 @@ ix86_expand_floorceildf_32 (rtx operand0, rtx operand1, bool do_floor) /* Temporary for holding the result, initialized to the input operand to ease control flow. */ - res = gen_reg_rtx (mode); - emit_move_insn (res, operand1); + res = copy_to_reg (operand1); /* xa = abs (operand1) */ xa = ix86_expand_sse_fabs (res, &mask); @@ -16490,10 +16492,10 @@ void ix86_expand_trunc (rtx operand0, rtx operand1) { /* C code for SSE variant we expand below. - double xa = fabs (x), x2; - if (!isless (xa, TWO52)) - return x; - x2 = (double)(long)x; + double xa = fabs (x), x2; + if (!isless (xa, TWO52)) + return x; + x2 = (double)(long)x; if (HONOR_SIGNED_ZEROS (mode)) return copysign (x2, x); return x2; @@ -16506,8 +16508,7 @@ ix86_expand_trunc (rtx operand0, rtx operand1) /* Temporary for holding the result, initialized to the input operand to ease control flow. */ - res = gen_reg_rtx (mode); - emit_move_insn (res, operand1); + res = copy_to_reg (operand1); /* xa = abs (operand1) */ xa = ix86_expand_sse_fabs (res, &mask); @@ -16516,7 +16517,7 @@ ix86_expand_trunc (rtx operand0, rtx operand1) label = ix86_expand_sse_compare_and_jump (UNLE, TWO52, xa, false); /* xa = (double)(long)x */ - xi = gen_reg_rtx (mode == DFmode ? DImode : SImode); + xi = gen_reg_rtx (int_mode_for_mode (mode).require ()); expand_fix (xi, res, 0); expand_float (xa, xi, 0); @@ -16542,23 +16543,22 @@ ix86_expand_truncdf_32 (rtx operand0, rtx operand1) rtx_code_label *label; /* C code for SSE variant we expand below. - double xa = fabs (x), x2; - if (!isless (xa, TWO52)) - return x; - xa2 = xa + TWO52 - TWO52; + double xa = fabs (x), x2; + if (!isless (xa, TWO52)) + return x; + xa2 = xa + TWO52 - TWO52; Compensate: - if (xa2 > xa) - xa2 -= 1.0; - x2 = copysign (xa2, x); - return x2; + if (xa2 > xa) + xa2 -= 1.0; + x2 = copysign (xa2, x); + return x2; */ TWO52 = ix86_gen_TWO52 (mode); /* Temporary for holding the result, initialized to the input operand to ease control flow. */ - res = gen_reg_rtx (mode); - emit_move_insn (res, operand1); + res =copy_to_reg (operand1); /* xa = abs (operand1) */ xa = ix86_expand_sse_fabs (res, &mask); @@ -16597,11 +16597,11 @@ void ix86_expand_round (rtx operand0, rtx operand1) { /* C code for the stuff we're doing below: - double xa = fabs (x); - if (!isless (xa, TWO52)) - return x; - xa = (double)(long)(xa + nextafter (0.5, 0.0)); - return copysign (xa, x); + double xa = fabs (x); + if (!isless (xa, TWO52)) + return x; + xa = (double)(long)(xa + nextafter (0.5, 0.0)); + return copysign (xa, x); */ machine_mode mode = GET_MODE (operand0); rtx res, TWO52, xa, xi, half, mask; @@ -16611,8 +16611,7 @@ ix86_expand_round (rtx operand0, rtx operand1) /* Temporary for holding the result, initialized to the input operand to ease control flow. */ - res = gen_reg_rtx (mode); - emit_move_insn (res, operand1); + res = copy_to_reg (operand1); TWO52 = ix86_gen_TWO52 (mode); xa = ix86_expand_sse_fabs (res, &mask); @@ -16628,7 +16627,7 @@ ix86_expand_round (rtx operand0, rtx operand1) xa = expand_simple_binop (mode, PLUS, xa, half, NULL_RTX, 0, OPTAB_DIRECT); /* xa = (double)(int64_t)xa */ - xi = gen_reg_rtx (mode == DFmode ? DImode : SImode); + xi = gen_reg_rtx (int_mode_for_mode (mode).require ()); expand_fix (xi, xa, 0); expand_float (xa, xi, 0); @@ -16648,20 +16647,20 @@ void ix86_expand_rounddf_32 (rtx operand0, rtx operand1) { /* C code for the stuff we expand below. - double xa = fabs (x), xa2, x2; - if (!isless (xa, TWO52)) - return x; + double xa = fabs (x), xa2, x2; + if (!isless (xa, TWO52)) + return x; Using the absolute value and copying back sign makes -0.0 -> -0.0 correct. - xa2 = xa + TWO52 - TWO52; + xa2 = xa + TWO52 - TWO52; Compensate. dxa = xa2 - xa; - if (dxa <= -0.5) - xa2 += 1; - else if (dxa > 0.5) - xa2 -= 1; - x2 = copysign (xa2, x); - return x2; + if (dxa <= -0.5) + xa2 += 1; + else if (dxa > 0.5) + xa2 -= 1; + x2 = copysign (xa2, x); + return x2; */ machine_mode mode = GET_MODE (operand0); rtx xa, xa2, dxa, TWO52, tmp, half, mhalf, one, res, mask; @@ -16671,8 +16670,7 @@ ix86_expand_rounddf_32 (rtx operand0, rtx operand1) /* Temporary for holding the result, initialized to the input operand to ease control flow. */ - res = gen_reg_rtx (mode); - emit_move_insn (res, operand1); + res = copy_to_reg (operand1); /* xa = abs (operand1) */ xa = ix86_expand_sse_fabs (res, &mask);