diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/i386/math-emu/fpu_tags.c |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/i386/math-emu/fpu_tags.c')
-rw-r--r-- | arch/i386/math-emu/fpu_tags.c | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/arch/i386/math-emu/fpu_tags.c b/arch/i386/math-emu/fpu_tags.c new file mode 100644 index 00000000000..cb436fe20e4 --- /dev/null +++ b/arch/i386/math-emu/fpu_tags.c @@ -0,0 +1,127 @@ +/*---------------------------------------------------------------------------+ + | fpu_tags.c | + | | + | Set FPU register tags. | + | | + | Copyright (C) 1997 | + | W. Metzenthen, 22 Parker St, Ormond, Vic 3163, Australia | + | E-mail billm@jacobi.maths.monash.edu.au | + | | + | | + +---------------------------------------------------------------------------*/ + +#include "fpu_emu.h" +#include "fpu_system.h" +#include "exception.h" + + +void FPU_pop(void) +{ + fpu_tag_word |= 3 << ((top & 7)*2); + top++; +} + + +int FPU_gettag0(void) +{ + return (fpu_tag_word >> ((top & 7)*2)) & 3; +} + + +int FPU_gettagi(int stnr) +{ + return (fpu_tag_word >> (((top+stnr) & 7)*2)) & 3; +} + + +int FPU_gettag(int regnr) +{ + return (fpu_tag_word >> ((regnr & 7)*2)) & 3; +} + + +void FPU_settag0(int tag) +{ + int regnr = top; + regnr &= 7; + fpu_tag_word &= ~(3 << (regnr*2)); + fpu_tag_word |= (tag & 3) << (regnr*2); +} + + +void FPU_settagi(int stnr, int tag) +{ + int regnr = stnr+top; + regnr &= 7; + fpu_tag_word &= ~(3 << (regnr*2)); + fpu_tag_word |= (tag & 3) << (regnr*2); +} + + +void FPU_settag(int regnr, int tag) +{ + regnr &= 7; + fpu_tag_word &= ~(3 << (regnr*2)); + fpu_tag_word |= (tag & 3) << (regnr*2); +} + + +int FPU_Special(FPU_REG const *ptr) +{ + int exp = exponent(ptr); + + if ( exp == EXP_BIAS+EXP_UNDER ) + return TW_Denormal; + else if ( exp != EXP_BIAS+EXP_OVER ) + return TW_NaN; + else if ( (ptr->sigh == 0x80000000) && (ptr->sigl == 0) ) + return TW_Infinity; + return TW_NaN; +} + + +int isNaN(FPU_REG const *ptr) +{ + return ( (exponent(ptr) == EXP_BIAS+EXP_OVER) + && !((ptr->sigh == 0x80000000) && (ptr->sigl == 0)) ); +} + + +int FPU_empty_i(int stnr) +{ + int regnr = (top+stnr) & 7; + + return ((fpu_tag_word >> (regnr*2)) & 3) == TAG_Empty; +} + + +int FPU_stackoverflow(FPU_REG **st_new_ptr) +{ + *st_new_ptr = &st(-1); + + return ((fpu_tag_word >> (((top - 1) & 7)*2)) & 3) != TAG_Empty; +} + + +void FPU_copy_to_regi(FPU_REG const *r, u_char tag, int stnr) +{ + reg_copy(r, &st(stnr)); + FPU_settagi(stnr, tag); +} + +void FPU_copy_to_reg1(FPU_REG const *r, u_char tag) +{ + reg_copy(r, &st(1)); + FPU_settagi(1, tag); +} + +void FPU_copy_to_reg0(FPU_REG const *r, u_char tag) +{ + int regnr = top; + regnr &= 7; + + reg_copy(r, &st(0)); + + fpu_tag_word &= ~(3 << (regnr*2)); + fpu_tag_word |= (tag & 3) << (regnr*2); +} |