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Diffstat (limited to 'arch/x86/math-emu/reg_mul.c')
-rw-r--r--arch/x86/math-emu/reg_mul.c163
1 files changed, 73 insertions, 90 deletions
diff --git a/arch/x86/math-emu/reg_mul.c b/arch/x86/math-emu/reg_mul.c
index 40f50b61bc67..36c37f71f713 100644
--- a/arch/x86/math-emu/reg_mul.c
+++ b/arch/x86/math-emu/reg_mul.c
@@ -20,7 +20,6 @@
#include "reg_constant.h"
#include "fpu_system.h"
-
/*
Multiply two registers to give a register result.
The sources are st(deststnr) and (b,tagb,signb).
@@ -29,104 +28,88 @@
/* This routine must be called with non-empty source registers */
int FPU_mul(FPU_REG const *b, u_char tagb, int deststnr, int control_w)
{
- FPU_REG *a = &st(deststnr);
- FPU_REG *dest = a;
- u_char taga = FPU_gettagi(deststnr);
- u_char saved_sign = getsign(dest);
- u_char sign = (getsign(a) ^ getsign(b));
- int tag;
-
+ FPU_REG *a = &st(deststnr);
+ FPU_REG *dest = a;
+ u_char taga = FPU_gettagi(deststnr);
+ u_char saved_sign = getsign(dest);
+ u_char sign = (getsign(a) ^ getsign(b));
+ int tag;
- if ( !(taga | tagb) )
- {
- /* Both regs Valid, this should be the most common case. */
+ if (!(taga | tagb)) {
+ /* Both regs Valid, this should be the most common case. */
- tag = FPU_u_mul(a, b, dest, control_w, sign, exponent(a) + exponent(b));
- if ( tag < 0 )
- {
- setsign(dest, saved_sign);
- return tag;
+ tag =
+ FPU_u_mul(a, b, dest, control_w, sign,
+ exponent(a) + exponent(b));
+ if (tag < 0) {
+ setsign(dest, saved_sign);
+ return tag;
+ }
+ FPU_settagi(deststnr, tag);
+ return tag;
}
- FPU_settagi(deststnr, tag);
- return tag;
- }
- if ( taga == TAG_Special )
- taga = FPU_Special(a);
- if ( tagb == TAG_Special )
- tagb = FPU_Special(b);
+ if (taga == TAG_Special)
+ taga = FPU_Special(a);
+ if (tagb == TAG_Special)
+ tagb = FPU_Special(b);
- if ( ((taga == TAG_Valid) && (tagb == TW_Denormal))
+ if (((taga == TAG_Valid) && (tagb == TW_Denormal))
|| ((taga == TW_Denormal) && (tagb == TAG_Valid))
- || ((taga == TW_Denormal) && (tagb == TW_Denormal)) )
- {
- FPU_REG x, y;
- if ( denormal_operand() < 0 )
- return FPU_Exception;
-
- FPU_to_exp16(a, &x);
- FPU_to_exp16(b, &y);
- tag = FPU_u_mul(&x, &y, dest, control_w, sign,
- exponent16(&x) + exponent16(&y));
- if ( tag < 0 )
- {
- setsign(dest, saved_sign);
- return tag;
- }
- FPU_settagi(deststnr, tag);
- return tag;
- }
- else if ( (taga <= TW_Denormal) && (tagb <= TW_Denormal) )
- {
- if ( ((tagb == TW_Denormal) || (taga == TW_Denormal))
- && (denormal_operand() < 0) )
- return FPU_Exception;
+ || ((taga == TW_Denormal) && (tagb == TW_Denormal))) {
+ FPU_REG x, y;
+ if (denormal_operand() < 0)
+ return FPU_Exception;
- /* Must have either both arguments == zero, or
- one valid and the other zero.
- The result is therefore zero. */
- FPU_copy_to_regi(&CONST_Z, TAG_Zero, deststnr);
- /* The 80486 book says that the answer is +0, but a real
- 80486 behaves this way.
- IEEE-754 apparently says it should be this way. */
- setsign(dest, sign);
- return TAG_Zero;
- }
- /* Must have infinities, NaNs, etc */
- else if ( (taga == TW_NaN) || (tagb == TW_NaN) )
- {
- return real_2op_NaN(b, tagb, deststnr, &st(0));
- }
- else if ( ((taga == TW_Infinity) && (tagb == TAG_Zero))
- || ((tagb == TW_Infinity) && (taga == TAG_Zero)) )
- {
- return arith_invalid(deststnr); /* Zero*Infinity is invalid */
- }
- else if ( ((taga == TW_Denormal) || (tagb == TW_Denormal))
- && (denormal_operand() < 0) )
- {
- return FPU_Exception;
- }
- else if (taga == TW_Infinity)
- {
- FPU_copy_to_regi(a, TAG_Special, deststnr);
- setsign(dest, sign);
- return TAG_Special;
- }
- else if (tagb == TW_Infinity)
- {
- FPU_copy_to_regi(b, TAG_Special, deststnr);
- setsign(dest, sign);
- return TAG_Special;
- }
+ FPU_to_exp16(a, &x);
+ FPU_to_exp16(b, &y);
+ tag = FPU_u_mul(&x, &y, dest, control_w, sign,
+ exponent16(&x) + exponent16(&y));
+ if (tag < 0) {
+ setsign(dest, saved_sign);
+ return tag;
+ }
+ FPU_settagi(deststnr, tag);
+ return tag;
+ } else if ((taga <= TW_Denormal) && (tagb <= TW_Denormal)) {
+ if (((tagb == TW_Denormal) || (taga == TW_Denormal))
+ && (denormal_operand() < 0))
+ return FPU_Exception;
+ /* Must have either both arguments == zero, or
+ one valid and the other zero.
+ The result is therefore zero. */
+ FPU_copy_to_regi(&CONST_Z, TAG_Zero, deststnr);
+ /* The 80486 book says that the answer is +0, but a real
+ 80486 behaves this way.
+ IEEE-754 apparently says it should be this way. */
+ setsign(dest, sign);
+ return TAG_Zero;
+ }
+ /* Must have infinities, NaNs, etc */
+ else if ((taga == TW_NaN) || (tagb == TW_NaN)) {
+ return real_2op_NaN(b, tagb, deststnr, &st(0));
+ } else if (((taga == TW_Infinity) && (tagb == TAG_Zero))
+ || ((tagb == TW_Infinity) && (taga == TAG_Zero))) {
+ return arith_invalid(deststnr); /* Zero*Infinity is invalid */
+ } else if (((taga == TW_Denormal) || (tagb == TW_Denormal))
+ && (denormal_operand() < 0)) {
+ return FPU_Exception;
+ } else if (taga == TW_Infinity) {
+ FPU_copy_to_regi(a, TAG_Special, deststnr);
+ setsign(dest, sign);
+ return TAG_Special;
+ } else if (tagb == TW_Infinity) {
+ FPU_copy_to_regi(b, TAG_Special, deststnr);
+ setsign(dest, sign);
+ return TAG_Special;
+ }
#ifdef PARANOID
- else
- {
- EXCEPTION(EX_INTERNAL|0x102);
- return FPU_Exception;
- }
-#endif /* PARANOID */
+ else {
+ EXCEPTION(EX_INTERNAL | 0x102);
+ return FPU_Exception;
+ }
+#endif /* PARANOID */
return 0;
}