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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/i386/math-emu/fpu_tags.c
Linux-2.6.12-rc2v2.6.12-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.c127
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 000000000000..cb436fe20e4c
--- /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);
+}