diff options
Diffstat (limited to 'gcc/config/i386/i386.c')
| -rw-r--r-- | gcc/config/i386/i386.c | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c index d2e19a0c293..cd416286015 100644 --- a/gcc/config/i386/i386.c +++ b/gcc/config/i386/i386.c @@ -4575,6 +4575,8 @@ init_ext_80387_constants (void) int standard_80387_constant_p (rtx x) { + REAL_VALUE_TYPE r; + if (GET_CODE (x) != CONST_DOUBLE || !FLOAT_MODE_P (GET_MODE (x))) return -1; @@ -4583,23 +4585,30 @@ standard_80387_constant_p (rtx x) if (x == CONST1_RTX (GET_MODE (x))) return 2; + REAL_VALUE_FROM_CONST_DOUBLE (r, x); + /* For XFmode constants, try to find a special 80387 instruction when optimizing for size or on those CPUs that benefit from them. */ if (GET_MODE (x) == XFmode && (optimize_size || x86_ext_80387_constants & TUNEMASK)) { - REAL_VALUE_TYPE r; int i; if (! ext_80387_constants_init) init_ext_80387_constants (); - REAL_VALUE_FROM_CONST_DOUBLE (r, x); for (i = 0; i < 5; i++) if (real_identical (&r, &ext_80387_constants_table[i])) return i + 3; } + /* Load of the constant -0.0 or -1.0 will be split as + fldz;fchs or fld1;fchs sequence. */ + if (real_isnegzero (&r)) + return 8; + if (real_identical (&r, &dconstm1)) + return 9; + return 0; } @@ -4625,6 +4634,9 @@ standard_80387_constant_opcode (rtx x) return "fldl2t"; case 7: return "fldpi"; + case 8: + case 9: + return "#"; default: gcc_unreachable (); } |