diff options
Diffstat (limited to 'sysdeps/i386/fpu/i386-math-asm.h')
| -rw-r--r-- | sysdeps/i386/fpu/i386-math-asm.h | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/sysdeps/i386/fpu/i386-math-asm.h b/sysdeps/i386/fpu/i386-math-asm.h index fd4313016c..c15029d2ee 100644 --- a/sysdeps/i386/fpu/i386-math-asm.h +++ b/sysdeps/i386/fpu/i386-math-asm.h @@ -36,4 +36,91 @@ addl $8, %esp; \ cfi_adjust_cfa_offset (-8); +/* Define constants for the minimum value of a floating-point + type. */ +#define DEFINE_FLT_MIN \ + .section .rodata.cst4,"aM",@progbits,4; \ + .p2align 2; \ + .type flt_min,@object; \ +flt_min: \ + .byte 0, 0, 0x80, 0; \ + .size flt_min, .-flt_min; +#define DEFINE_DBL_MIN \ + .section .rodata.cst8,"aM",@progbits,8; \ + .p2align 3; \ + .type dbl_min,@object; \ +dbl_min: \ + .byte 0, 0, 0, 0, 0, 0, 0x10, 0; \ + .size dbl_min, .-dbl_min; + +/* Remove excess range and precision by storing a value on the stack + and loading it back. The value is given to be nonnegative or NaN; + if it is subnormal, also force an underflow exception. The + relevant constant for the minimum of the type must have been + defined, the MO macro must have been defined for access to memory + operands, and, if PIC, the PIC register must have been loaded. */ +#define FLT_NARROW_EVAL_UFLOW_NONNEG_NAN \ + subl $4, %esp; \ + cfi_adjust_cfa_offset (4); \ + flds MO(flt_min); \ + fld %st(1); \ + fucompp; \ + fnstsw; \ + sahf; \ + jnc 6424f; \ + fld %st(0); \ + fmul %st(0); \ + fstps (%esp); \ +6424: fstps (%esp); \ + flds (%esp); \ + addl $4, %esp; \ + cfi_adjust_cfa_offset (-4); +#define DBL_NARROW_EVAL_UFLOW_NONNEG_NAN \ + subl $8, %esp; \ + cfi_adjust_cfa_offset (8); \ + fldl MO(dbl_min); \ + fld %st(1); \ + fucompp; \ + fnstsw; \ + sahf; \ + jnc 6453f; \ + fld %st(0); \ + fmul %st(0); \ + fstpl (%esp); \ +6453: fstpl (%esp); \ + fldl (%esp); \ + addl $8, %esp; \ + cfi_adjust_cfa_offset (-8); + +/* Likewise, but the argument is not a NaN (so fcom instructions, + which support memory operands, can be used). */ +#define FLT_NARROW_EVAL_UFLOW_NONNEG \ + subl $4, %esp; \ + cfi_adjust_cfa_offset (4); \ + fcoms MO(flt_min); \ + fnstsw; \ + sahf; \ + jnc 6424f; \ + fld %st(0); \ + fmul %st(0); \ + fstps (%esp); \ +6424: fstps (%esp); \ + flds (%esp); \ + addl $4, %esp; \ + cfi_adjust_cfa_offset (-4); +#define DBL_NARROW_EVAL_UFLOW_NONNEG \ + subl $8, %esp; \ + cfi_adjust_cfa_offset (8); \ + fcoml MO(dbl_min); \ + fnstsw; \ + sahf; \ + jnc 6453f; \ + fld %st(0); \ + fmul %st(0); \ + fstpl (%esp); \ +6453: fstpl (%esp); \ + fldl (%esp); \ + addl $8, %esp; \ + cfi_adjust_cfa_offset (-8); + #endif /* i386-math-asm.h. */ |