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Diffstat (limited to 'arch/x86/math-emu/reg_compare.c')
-rw-r--r--arch/x86/math-emu/reg_compare.c567
1 files changed, 268 insertions, 299 deletions
diff --git a/arch/x86/math-emu/reg_compare.c b/arch/x86/math-emu/reg_compare.c
index f37c5b5a35ad..ecce55fc2e2e 100644
--- a/arch/x86/math-emu/reg_compare.c
+++ b/arch/x86/math-emu/reg_compare.c
@@ -20,362 +20,331 @@
#include "control_w.h"
#include "status_w.h"
-
static int compare(FPU_REG const *b, int tagb)
{
- int diff, exp0, expb;
- u_char st0_tag;
- FPU_REG *st0_ptr;
- FPU_REG x, y;
- u_char st0_sign, signb = getsign(b);
-
- st0_ptr = &st(0);
- st0_tag = FPU_gettag0();
- st0_sign = getsign(st0_ptr);
-
- if ( tagb == TAG_Special )
- tagb = FPU_Special(b);
- if ( st0_tag == TAG_Special )
- st0_tag = FPU_Special(st0_ptr);
-
- if ( ((st0_tag != TAG_Valid) && (st0_tag != TW_Denormal))
- || ((tagb != TAG_Valid) && (tagb != TW_Denormal)) )
- {
- if ( st0_tag == TAG_Zero )
- {
- if ( tagb == TAG_Zero ) return COMP_A_eq_B;
- if ( tagb == TAG_Valid )
- return ((signb == SIGN_POS) ? COMP_A_lt_B : COMP_A_gt_B);
- if ( tagb == TW_Denormal )
- return ((signb == SIGN_POS) ? COMP_A_lt_B : COMP_A_gt_B)
- | COMP_Denormal;
- }
- else if ( tagb == TAG_Zero )
- {
- if ( st0_tag == TAG_Valid )
- return ((st0_sign == SIGN_POS) ? COMP_A_gt_B : COMP_A_lt_B);
- if ( st0_tag == TW_Denormal )
- return ((st0_sign == SIGN_POS) ? COMP_A_gt_B : COMP_A_lt_B)
- | COMP_Denormal;
+ int diff, exp0, expb;
+ u_char st0_tag;
+ FPU_REG *st0_ptr;
+ FPU_REG x, y;
+ u_char st0_sign, signb = getsign(b);
+
+ st0_ptr = &st(0);
+ st0_tag = FPU_gettag0();
+ st0_sign = getsign(st0_ptr);
+
+ if (tagb == TAG_Special)
+ tagb = FPU_Special(b);
+ if (st0_tag == TAG_Special)
+ st0_tag = FPU_Special(st0_ptr);
+
+ if (((st0_tag != TAG_Valid) && (st0_tag != TW_Denormal))
+ || ((tagb != TAG_Valid) && (tagb != TW_Denormal))) {
+ if (st0_tag == TAG_Zero) {
+ if (tagb == TAG_Zero)
+ return COMP_A_eq_B;
+ if (tagb == TAG_Valid)
+ return ((signb ==
+ SIGN_POS) ? COMP_A_lt_B : COMP_A_gt_B);
+ if (tagb == TW_Denormal)
+ return ((signb ==
+ SIGN_POS) ? COMP_A_lt_B : COMP_A_gt_B)
+ | COMP_Denormal;
+ } else if (tagb == TAG_Zero) {
+ if (st0_tag == TAG_Valid)
+ return ((st0_sign ==
+ SIGN_POS) ? COMP_A_gt_B : COMP_A_lt_B);
+ if (st0_tag == TW_Denormal)
+ return ((st0_sign ==
+ SIGN_POS) ? COMP_A_gt_B : COMP_A_lt_B)
+ | COMP_Denormal;
+ }
+
+ if (st0_tag == TW_Infinity) {
+ if ((tagb == TAG_Valid) || (tagb == TAG_Zero))
+ return ((st0_sign ==
+ SIGN_POS) ? COMP_A_gt_B : COMP_A_lt_B);
+ else if (tagb == TW_Denormal)
+ return ((st0_sign ==
+ SIGN_POS) ? COMP_A_gt_B : COMP_A_lt_B)
+ | COMP_Denormal;
+ else if (tagb == TW_Infinity) {
+ /* The 80486 book says that infinities can be equal! */
+ return (st0_sign == signb) ? COMP_A_eq_B :
+ ((st0_sign ==
+ SIGN_POS) ? COMP_A_gt_B : COMP_A_lt_B);
+ }
+ /* Fall through to the NaN code */
+ } else if (tagb == TW_Infinity) {
+ if ((st0_tag == TAG_Valid) || (st0_tag == TAG_Zero))
+ return ((signb ==
+ SIGN_POS) ? COMP_A_lt_B : COMP_A_gt_B);
+ if (st0_tag == TW_Denormal)
+ return ((signb ==
+ SIGN_POS) ? COMP_A_lt_B : COMP_A_gt_B)
+ | COMP_Denormal;
+ /* Fall through to the NaN code */
+ }
+
+ /* The only possibility now should be that one of the arguments
+ is a NaN */
+ if ((st0_tag == TW_NaN) || (tagb == TW_NaN)) {
+ int signalling = 0, unsupported = 0;
+ if (st0_tag == TW_NaN) {
+ signalling =
+ (st0_ptr->sigh & 0xc0000000) == 0x80000000;
+ unsupported = !((exponent(st0_ptr) == EXP_OVER)
+ && (st0_ptr->
+ sigh & 0x80000000));
+ }
+ if (tagb == TW_NaN) {
+ signalling |=
+ (b->sigh & 0xc0000000) == 0x80000000;
+ unsupported |= !((exponent(b) == EXP_OVER)
+ && (b->sigh & 0x80000000));
+ }
+ if (signalling || unsupported)
+ return COMP_No_Comp | COMP_SNaN | COMP_NaN;
+ else
+ /* Neither is a signaling NaN */
+ return COMP_No_Comp | COMP_NaN;
+ }
+
+ EXCEPTION(EX_Invalid);
}
- if ( st0_tag == TW_Infinity )
- {
- if ( (tagb == TAG_Valid) || (tagb == TAG_Zero) )
- return ((st0_sign == SIGN_POS) ? COMP_A_gt_B : COMP_A_lt_B);
- else if ( tagb == TW_Denormal )
- return ((st0_sign == SIGN_POS) ? COMP_A_gt_B : COMP_A_lt_B)
- | COMP_Denormal;
- else if ( tagb == TW_Infinity )
- {
- /* The 80486 book says that infinities can be equal! */
- return (st0_sign == signb) ? COMP_A_eq_B :
- ((st0_sign == SIGN_POS) ? COMP_A_gt_B : COMP_A_lt_B);
- }
- /* Fall through to the NaN code */
- }
- else if ( tagb == TW_Infinity )
- {
- if ( (st0_tag == TAG_Valid) || (st0_tag == TAG_Zero) )
- return ((signb == SIGN_POS) ? COMP_A_lt_B : COMP_A_gt_B);
- if ( st0_tag == TW_Denormal )
- return ((signb == SIGN_POS) ? COMP_A_lt_B : COMP_A_gt_B)
- | COMP_Denormal;
- /* Fall through to the NaN code */
+ if (st0_sign != signb) {
+ return ((st0_sign == SIGN_POS) ? COMP_A_gt_B : COMP_A_lt_B)
+ | (((st0_tag == TW_Denormal) || (tagb == TW_Denormal)) ?
+ COMP_Denormal : 0);
}
- /* The only possibility now should be that one of the arguments
- is a NaN */
- if ( (st0_tag == TW_NaN) || (tagb == TW_NaN) )
- {
- int signalling = 0, unsupported = 0;
- if ( st0_tag == TW_NaN )
- {
- signalling = (st0_ptr->sigh & 0xc0000000) == 0x80000000;
- unsupported = !((exponent(st0_ptr) == EXP_OVER)
- && (st0_ptr->sigh & 0x80000000));
- }
- if ( tagb == TW_NaN )
- {
- signalling |= (b->sigh & 0xc0000000) == 0x80000000;
- unsupported |= !((exponent(b) == EXP_OVER)
- && (b->sigh & 0x80000000));
- }
- if ( signalling || unsupported )
- return COMP_No_Comp | COMP_SNaN | COMP_NaN;
- else
- /* Neither is a signaling NaN */
- return COMP_No_Comp | COMP_NaN;
+ if ((st0_tag == TW_Denormal) || (tagb == TW_Denormal)) {
+ FPU_to_exp16(st0_ptr, &x);
+ FPU_to_exp16(b, &y);
+ st0_ptr = &x;
+ b = &y;
+ exp0 = exponent16(st0_ptr);
+ expb = exponent16(b);
+ } else {
+ exp0 = exponent(st0_ptr);
+ expb = exponent(b);
}
-
- EXCEPTION(EX_Invalid);
- }
-
- if (st0_sign != signb)
- {
- return ((st0_sign == SIGN_POS) ? COMP_A_gt_B : COMP_A_lt_B)
- | ( ((st0_tag == TW_Denormal) || (tagb == TW_Denormal)) ?
- COMP_Denormal : 0);
- }
-
- if ( (st0_tag == TW_Denormal) || (tagb == TW_Denormal) )
- {
- FPU_to_exp16(st0_ptr, &x);
- FPU_to_exp16(b, &y);
- st0_ptr = &x;
- b = &y;
- exp0 = exponent16(st0_ptr);
- expb = exponent16(b);
- }
- else
- {
- exp0 = exponent(st0_ptr);
- expb = exponent(b);
- }
#ifdef PARANOID
- if (!(st0_ptr->sigh & 0x80000000)) EXCEPTION(EX_Invalid);
- if (!(b->sigh & 0x80000000)) EXCEPTION(EX_Invalid);
+ if (!(st0_ptr->sigh & 0x80000000))
+ EXCEPTION(EX_Invalid);
+ if (!(b->sigh & 0x80000000))
+ EXCEPTION(EX_Invalid);
#endif /* PARANOID */
- diff = exp0 - expb;
- if ( diff == 0 )
- {
- diff = st0_ptr->sigh - b->sigh; /* Works only if ms bits are
- identical */
- if ( diff == 0 )
- {
- diff = st0_ptr->sigl > b->sigl;
- if ( diff == 0 )
- diff = -(st0_ptr->sigl < b->sigl);
+ diff = exp0 - expb;
+ if (diff == 0) {
+ diff = st0_ptr->sigh - b->sigh; /* Works only if ms bits are
+ identical */
+ if (diff == 0) {
+ diff = st0_ptr->sigl > b->sigl;
+ if (diff == 0)
+ diff = -(st0_ptr->sigl < b->sigl);
+ }
}
- }
-
- if ( diff > 0 )
- {
- return ((st0_sign == SIGN_POS) ? COMP_A_gt_B : COMP_A_lt_B)
- | ( ((st0_tag == TW_Denormal) || (tagb == TW_Denormal)) ?
- COMP_Denormal : 0);
- }
- if ( diff < 0 )
- {
- return ((st0_sign == SIGN_POS) ? COMP_A_lt_B : COMP_A_gt_B)
- | ( ((st0_tag == TW_Denormal) || (tagb == TW_Denormal)) ?
- COMP_Denormal : 0);
- }
-
- return COMP_A_eq_B
- | ( ((st0_tag == TW_Denormal) || (tagb == TW_Denormal)) ?
- COMP_Denormal : 0);
-}
+ if (diff > 0) {
+ return ((st0_sign == SIGN_POS) ? COMP_A_gt_B : COMP_A_lt_B)
+ | (((st0_tag == TW_Denormal) || (tagb == TW_Denormal)) ?
+ COMP_Denormal : 0);
+ }
+ if (diff < 0) {
+ return ((st0_sign == SIGN_POS) ? COMP_A_lt_B : COMP_A_gt_B)
+ | (((st0_tag == TW_Denormal) || (tagb == TW_Denormal)) ?
+ COMP_Denormal : 0);
+ }
+ return COMP_A_eq_B
+ | (((st0_tag == TW_Denormal) || (tagb == TW_Denormal)) ?
+ COMP_Denormal : 0);
+
+}
/* This function requires that st(0) is not empty */
int FPU_compare_st_data(FPU_REG const *loaded_data, u_char loaded_tag)
{
- int f = 0, c;
-
- c = compare(loaded_data, loaded_tag);
-
- if (c & COMP_NaN)
- {
- EXCEPTION(EX_Invalid);
- f = SW_C3 | SW_C2 | SW_C0;
- }
- else
- switch (c & 7)
- {
- case COMP_A_lt_B:
- f = SW_C0;
- break;
- case COMP_A_eq_B:
- f = SW_C3;
- break;
- case COMP_A_gt_B:
- f = 0;
- break;
- case COMP_No_Comp:
- f = SW_C3 | SW_C2 | SW_C0;
- break;
+ int f = 0, c;
+
+ c = compare(loaded_data, loaded_tag);
+
+ if (c & COMP_NaN) {
+ EXCEPTION(EX_Invalid);
+ f = SW_C3 | SW_C2 | SW_C0;
+ } else
+ switch (c & 7) {
+ case COMP_A_lt_B:
+ f = SW_C0;
+ break;
+ case COMP_A_eq_B:
+ f = SW_C3;
+ break;
+ case COMP_A_gt_B:
+ f = 0;
+ break;
+ case COMP_No_Comp:
+ f = SW_C3 | SW_C2 | SW_C0;
+ break;
#ifdef PARANOID
- default:
- EXCEPTION(EX_INTERNAL|0x121);
- f = SW_C3 | SW_C2 | SW_C0;
- break;
+ default:
+ EXCEPTION(EX_INTERNAL | 0x121);
+ f = SW_C3 | SW_C2 | SW_C0;
+ break;
#endif /* PARANOID */
- }
- setcc(f);
- if (c & COMP_Denormal)
- {
- return denormal_operand() < 0;
- }
- return 0;
+ }
+ setcc(f);
+ if (c & COMP_Denormal) {
+ return denormal_operand() < 0;
+ }
+ return 0;
}
-
static int compare_st_st(int nr)
{
- int f = 0, c;
- FPU_REG *st_ptr;
-
- if ( !NOT_EMPTY(0) || !NOT_EMPTY(nr) )
- {
- setcc(SW_C3 | SW_C2 | SW_C0);
- /* Stack fault */
- EXCEPTION(EX_StackUnder);
- return !(control_word & CW_Invalid);
- }
-
- st_ptr = &st(nr);
- c = compare(st_ptr, FPU_gettagi(nr));
- if (c & COMP_NaN)
- {
- setcc(SW_C3 | SW_C2 | SW_C0);
- EXCEPTION(EX_Invalid);
- return !(control_word & CW_Invalid);
- }
- else
- switch (c & 7)
- {
- case COMP_A_lt_B:
- f = SW_C0;
- break;
- case COMP_A_eq_B:
- f = SW_C3;
- break;
- case COMP_A_gt_B:
- f = 0;
- break;
- case COMP_No_Comp:
- f = SW_C3 | SW_C2 | SW_C0;
- break;
+ int f = 0, c;
+ FPU_REG *st_ptr;
+
+ if (!NOT_EMPTY(0) || !NOT_EMPTY(nr)) {
+ setcc(SW_C3 | SW_C2 | SW_C0);
+ /* Stack fault */
+ EXCEPTION(EX_StackUnder);
+ return !(control_word & CW_Invalid);
+ }
+
+ st_ptr = &st(nr);
+ c = compare(st_ptr, FPU_gettagi(nr));
+ if (c & COMP_NaN) {
+ setcc(SW_C3 | SW_C2 | SW_C0);
+ EXCEPTION(EX_Invalid);
+ return !(control_word & CW_Invalid);
+ } else
+ switch (c & 7) {
+ case COMP_A_lt_B:
+ f = SW_C0;
+ break;
+ case COMP_A_eq_B:
+ f = SW_C3;
+ break;
+ case COMP_A_gt_B:
+ f = 0;
+ break;
+ case COMP_No_Comp:
+ f = SW_C3 | SW_C2 | SW_C0;
+ break;
#ifdef PARANOID
- default:
- EXCEPTION(EX_INTERNAL|0x122);
- f = SW_C3 | SW_C2 | SW_C0;
- break;
+ default:
+ EXCEPTION(EX_INTERNAL | 0x122);
+ f = SW_C3 | SW_C2 | SW_C0;
+ break;
#endif /* PARANOID */
- }
- setcc(f);
- if (c & COMP_Denormal)
- {
- return denormal_operand() < 0;
- }
- return 0;
+ }
+ setcc(f);
+ if (c & COMP_Denormal) {
+ return denormal_operand() < 0;
+ }
+ return 0;
}
-
static int compare_u_st_st(int nr)
{
- int f = 0, c;
- FPU_REG *st_ptr;
-
- if ( !NOT_EMPTY(0) || !NOT_EMPTY(nr) )
- {
- setcc(SW_C3 | SW_C2 | SW_C0);
- /* Stack fault */
- EXCEPTION(EX_StackUnder);
- return !(control_word & CW_Invalid);
- }
-
- st_ptr = &st(nr);
- c = compare(st_ptr, FPU_gettagi(nr));
- if (c & COMP_NaN)
- {
- setcc(SW_C3 | SW_C2 | SW_C0);
- if (c & COMP_SNaN) /* This is the only difference between
- un-ordered and ordinary comparisons */
- {
- EXCEPTION(EX_Invalid);
- return !(control_word & CW_Invalid);
+ int f = 0, c;
+ FPU_REG *st_ptr;
+
+ if (!NOT_EMPTY(0) || !NOT_EMPTY(nr)) {
+ setcc(SW_C3 | SW_C2 | SW_C0);
+ /* Stack fault */
+ EXCEPTION(EX_StackUnder);
+ return !(control_word & CW_Invalid);
}
- return 0;
- }
- else
- switch (c & 7)
- {
- case COMP_A_lt_B:
- f = SW_C0;
- break;
- case COMP_A_eq_B:
- f = SW_C3;
- break;
- case COMP_A_gt_B:
- f = 0;
- break;
- case COMP_No_Comp:
- f = SW_C3 | SW_C2 | SW_C0;
- break;
+
+ st_ptr = &st(nr);
+ c = compare(st_ptr, FPU_gettagi(nr));
+ if (c & COMP_NaN) {
+ setcc(SW_C3 | SW_C2 | SW_C0);
+ if (c & COMP_SNaN) { /* This is the only difference between
+ un-ordered and ordinary comparisons */
+ EXCEPTION(EX_Invalid);
+ return !(control_word & CW_Invalid);
+ }
+ return 0;
+ } else
+ switch (c & 7) {
+ case COMP_A_lt_B:
+ f = SW_C0;
+ break;
+ case COMP_A_eq_B:
+ f = SW_C3;
+ break;
+ case COMP_A_gt_B:
+ f = 0;
+ break;
+ case COMP_No_Comp:
+ f = SW_C3 | SW_C2 | SW_C0;
+ break;
#ifdef PARANOID
- default:
- EXCEPTION(EX_INTERNAL|0x123);
- f = SW_C3 | SW_C2 | SW_C0;
- break;
-#endif /* PARANOID */
- }
- setcc(f);
- if (c & COMP_Denormal)
- {
- return denormal_operand() < 0;
- }
- return 0;
+ default:
+ EXCEPTION(EX_INTERNAL | 0x123);
+ f = SW_C3 | SW_C2 | SW_C0;
+ break;
+#endif /* PARANOID */
+ }
+ setcc(f);
+ if (c & COMP_Denormal) {
+ return denormal_operand() < 0;
+ }
+ return 0;
}
/*---------------------------------------------------------------------------*/
void fcom_st(void)
{
- /* fcom st(i) */
- compare_st_st(FPU_rm);
+ /* fcom st(i) */
+ compare_st_st(FPU_rm);
}
-
void fcompst(void)
{
- /* fcomp st(i) */
- if ( !compare_st_st(FPU_rm) )
- FPU_pop();
+ /* fcomp st(i) */
+ if (!compare_st_st(FPU_rm))
+ FPU_pop();
}
-
void fcompp(void)
{
- /* fcompp */
- if (FPU_rm != 1)
- {
- FPU_illegal();
- return;
- }
- if ( !compare_st_st(1) )
- poppop();
+ /* fcompp */
+ if (FPU_rm != 1) {
+ FPU_illegal();
+ return;
+ }
+ if (!compare_st_st(1))
+ poppop();
}
-
void fucom_(void)
{
- /* fucom st(i) */
- compare_u_st_st(FPU_rm);
+ /* fucom st(i) */
+ compare_u_st_st(FPU_rm);
}
-
void fucomp(void)
{
- /* fucomp st(i) */
- if ( !compare_u_st_st(FPU_rm) )
- FPU_pop();
+ /* fucomp st(i) */
+ if (!compare_u_st_st(FPU_rm))
+ FPU_pop();
}
-
void fucompp(void)
{
- /* fucompp */
- if (FPU_rm == 1)
- {
- if ( !compare_u_st_st(1) )
- poppop();
- }
- else
- FPU_illegal();
+ /* fucompp */
+ if (FPU_rm == 1) {
+ if (!compare_u_st_st(1))
+ poppop();
+ } else
+ FPU_illegal();
}
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-22 04:03:46 +0300