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Diffstat (limited to 'arch/x86/math-emu/reg_divide.c')
-rw-r--r--arch/x86/math-emu/reg_divide.c301
1 files changed, 138 insertions, 163 deletions
diff --git a/arch/x86/math-emu/reg_divide.c b/arch/x86/math-emu/reg_divide.c
index 5cee7ff920d..6827012db34 100644
--- a/arch/x86/math-emu/reg_divide.c
+++ b/arch/x86/math-emu/reg_divide.c
@@ -26,182 +26,157 @@
*/
int FPU_div(int flags, int rm, int control_w)
{
- FPU_REG x, y;
- FPU_REG const *a, *b, *st0_ptr, *st_ptr;
- FPU_REG *dest;
- u_char taga, tagb, signa, signb, sign, saved_sign;
- int tag, deststnr;
-
- if ( flags & DEST_RM )
- deststnr = rm;
- else
- deststnr = 0;
-
- if ( flags & REV )
- {
- b = &st(0);
- st0_ptr = b;
- tagb = FPU_gettag0();
- if ( flags & LOADED )
- {
- a = (FPU_REG *)rm;
- taga = flags & 0x0f;
+ FPU_REG x, y;
+ FPU_REG const *a, *b, *st0_ptr, *st_ptr;
+ FPU_REG *dest;
+ u_char taga, tagb, signa, signb, sign, saved_sign;
+ int tag, deststnr;
+
+ if (flags & DEST_RM)
+ deststnr = rm;
+ else
+ deststnr = 0;
+
+ if (flags & REV) {
+ b = &st(0);
+ st0_ptr = b;
+ tagb = FPU_gettag0();
+ if (flags & LOADED) {
+ a = (FPU_REG *) rm;
+ taga = flags & 0x0f;
+ } else {
+ a = &st(rm);
+ st_ptr = a;
+ taga = FPU_gettagi(rm);
+ }
+ } else {
+ a = &st(0);
+ st0_ptr = a;
+ taga = FPU_gettag0();
+ if (flags & LOADED) {
+ b = (FPU_REG *) rm;
+ tagb = flags & 0x0f;
+ } else {
+ b = &st(rm);
+ st_ptr = b;
+ tagb = FPU_gettagi(rm);
+ }
}
- else
- {
- a = &st(rm);
- st_ptr = a;
- taga = FPU_gettagi(rm);
- }
- }
- else
- {
- a = &st(0);
- st0_ptr = a;
- taga = FPU_gettag0();
- if ( flags & LOADED )
- {
- b = (FPU_REG *)rm;
- tagb = flags & 0x0f;
- }
- else
- {
- b = &st(rm);
- st_ptr = b;
- tagb = FPU_gettagi(rm);
- }
- }
- signa = getsign(a);
- signb = getsign(b);
+ signa = getsign(a);
+ signb = getsign(b);
- sign = signa ^ signb;
+ sign = signa ^ signb;
- dest = &st(deststnr);
- saved_sign = getsign(dest);
+ dest = &st(deststnr);
+ saved_sign = getsign(dest);
- if ( !(taga | tagb) )
- {
- /* Both regs Valid, this should be the most common case. */
- reg_copy(a, &x);
- reg_copy(b, &y);
- setpositive(&x);
- setpositive(&y);
- tag = FPU_u_div(&x, &y, dest, control_w, sign);
+ if (!(taga | tagb)) {
+ /* Both regs Valid, this should be the most common case. */
+ reg_copy(a, &x);
+ reg_copy(b, &y);
+ setpositive(&x);
+ setpositive(&y);
+ tag = FPU_u_div(&x, &y, dest, control_w, sign);
- if ( tag < 0 )
- return tag;
+ if (tag < 0)
+ 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)) )
- {
- if ( denormal_operand() < 0 )
- return FPU_Exception;
-
- FPU_to_exp16(a, &x);
- FPU_to_exp16(b, &y);
- tag = FPU_u_div(&x, &y, dest, control_w, sign);
- if ( tag < 0 )
- return tag;
-
- FPU_settagi(deststnr, tag);
- return tag;
- }
- else if ( (taga <= TW_Denormal) && (tagb <= TW_Denormal) )
- {
- if ( tagb != TAG_Zero )
- {
- /* Want to find Zero/Valid */
- if ( tagb == TW_Denormal )
- {
- if ( denormal_operand() < 0 )
- return FPU_Exception;
- }
-
- /* The result is zero. */
- FPU_copy_to_regi(&CONST_Z, TAG_Zero, deststnr);
- setsign(dest, sign);
- return TAG_Zero;
+ || ((taga == TW_Denormal) && (tagb == TW_Denormal))) {
+ if (denormal_operand() < 0)
+ return FPU_Exception;
+
+ FPU_to_exp16(a, &x);
+ FPU_to_exp16(b, &y);
+ tag = FPU_u_div(&x, &y, dest, control_w, sign);
+ if (tag < 0)
+ return tag;
+
+ FPU_settagi(deststnr, tag);
+ return tag;
+ } else if ((taga <= TW_Denormal) && (tagb <= TW_Denormal)) {
+ if (tagb != TAG_Zero) {
+ /* Want to find Zero/Valid */
+ if (tagb == TW_Denormal) {
+ if (denormal_operand() < 0)
+ return FPU_Exception;
+ }
+
+ /* The result is zero. */
+ FPU_copy_to_regi(&CONST_Z, TAG_Zero, deststnr);
+ setsign(dest, sign);
+ return TAG_Zero;
+ }
+ /* We have an exception condition, either 0/0 or Valid/Zero. */
+ if (taga == TAG_Zero) {
+ /* 0/0 */
+ return arith_invalid(deststnr);
+ }
+ /* Valid/Zero */
+ return FPU_divide_by_zero(deststnr, sign);
}
- /* We have an exception condition, either 0/0 or Valid/Zero. */
- if ( taga == TAG_Zero )
- {
- /* 0/0 */
- return arith_invalid(deststnr);
+ /* Must have infinities, NaNs, etc */
+ else if ((taga == TW_NaN) || (tagb == TW_NaN)) {
+ if (flags & LOADED)
+ return real_2op_NaN((FPU_REG *) rm, flags & 0x0f, 0,
+ st0_ptr);
+
+ if (flags & DEST_RM) {
+ int tag;
+ tag = FPU_gettag0();
+ if (tag == TAG_Special)
+ tag = FPU_Special(st0_ptr);
+ return real_2op_NaN(st0_ptr, tag, rm,
+ (flags & REV) ? st0_ptr : &st(rm));
+ } else {
+ int tag;
+ tag = FPU_gettagi(rm);
+ if (tag == TAG_Special)
+ tag = FPU_Special(&st(rm));
+ return real_2op_NaN(&st(rm), tag, 0,
+ (flags & REV) ? st0_ptr : &st(rm));
+ }
+ } else if (taga == TW_Infinity) {
+ if (tagb == TW_Infinity) {
+ /* infinity/infinity */
+ return arith_invalid(deststnr);
+ } else {
+ /* tagb must be Valid or Zero */
+ if ((tagb == TW_Denormal) && (denormal_operand() < 0))
+ return FPU_Exception;
+
+ /* Infinity divided by Zero or Valid does
+ not raise and exception, but returns Infinity */
+ FPU_copy_to_regi(a, TAG_Special, deststnr);
+ setsign(dest, sign);
+ return taga;
+ }
+ } else if (tagb == TW_Infinity) {
+ if ((taga == TW_Denormal) && (denormal_operand() < 0))
+ return FPU_Exception;
+
+ /* The result is zero. */
+ FPU_copy_to_regi(&CONST_Z, TAG_Zero, deststnr);
+ setsign(dest, sign);
+ return TAG_Zero;
}
- /* Valid/Zero */
- return FPU_divide_by_zero(deststnr, sign);
- }
- /* Must have infinities, NaNs, etc */
- else if ( (taga == TW_NaN) || (tagb == TW_NaN) )
- {
- if ( flags & LOADED )
- return real_2op_NaN((FPU_REG *)rm, flags & 0x0f, 0, st0_ptr);
-
- if ( flags & DEST_RM )
- {
- int tag;
- tag = FPU_gettag0();
- if ( tag == TAG_Special )
- tag = FPU_Special(st0_ptr);
- return real_2op_NaN(st0_ptr, tag, rm, (flags & REV) ? st0_ptr : &st(rm));
- }
- else
- {
- int tag;
- tag = FPU_gettagi(rm);
- if ( tag == TAG_Special )
- tag = FPU_Special(&st(rm));
- return real_2op_NaN(&st(rm), tag, 0, (flags & REV) ? st0_ptr : &st(rm));
- }
- }
- else if (taga == TW_Infinity)
- {
- if (tagb == TW_Infinity)
- {
- /* infinity/infinity */
- return arith_invalid(deststnr);
- }
- else
- {
- /* tagb must be Valid or Zero */
- if ( (tagb == TW_Denormal) && (denormal_operand() < 0) )
- return FPU_Exception;
-
- /* Infinity divided by Zero or Valid does
- not raise and exception, but returns Infinity */
- FPU_copy_to_regi(a, TAG_Special, deststnr);
- setsign(dest, sign);
- return taga;
- }
- }
- else if (tagb == TW_Infinity)
- {
- if ( (taga == TW_Denormal) && (denormal_operand() < 0) )
- return FPU_Exception;
-
- /* The result is zero. */
- FPU_copy_to_regi(&CONST_Z, TAG_Zero, deststnr);
- setsign(dest, sign);
- return TAG_Zero;
- }
#ifdef PARANOID
- else
- {
- EXCEPTION(EX_INTERNAL|0x102);
- return FPU_Exception;
- }
-#endif /* PARANOID */
+ else {
+ EXCEPTION(EX_INTERNAL | 0x102);
+ return FPU_Exception;
+ }
+#endif /* PARANOID */
return 0;
}