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target-tricore: properly fix dvinit_b/h_13

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The TriCore documentation was wrong on how to calculate ovf bits for those two
instructions, which I confirmed with real hardware (TC1796 chip). An ovf
actually happens, if the result (without remainder) does not fit into 8/16 bits.

Signed-off-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
This commit is contained in:
Bastian Koppelmann 2015-03-23 18:24:42 +01:00
parent 00e1754ff1
commit f69c24e458
1 changed files with 10 additions and 30 deletions
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40
target-tricore/op_helper.c
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@ -1942,29 +1942,19 @@ uint64_t helper_unpack(target_ulong arg1)
uint64_t helper_dvinit_b_13(CPUTriCoreState *env, uint32_t r1, uint32_t r2)
{
uint64_t ret;
int32_t abs_sig_dividend, abs_base_dividend, abs_divisor;
int32_t quotient_sign;
int32_t abs_sig_dividend, abs_divisor;
ret = sextract32(r1, 0, 32);
ret = ret << 24;
quotient_sign = 0;
if (!((r1 & 0x80000000) == (r2 & 0x80000000))) {
ret |= 0xffffff;
quotient_sign = 1;
}
abs_sig_dividend = abs((int32_t)r1) >> 7;
abs_base_dividend = abs((int32_t)r1) & 0x7f;
abs_sig_dividend = abs((int32_t)r1) >> 8;
abs_divisor = abs((int32_t)r2);
/* calc overflow */
env->PSW_USB_V = 0;
if ((quotient_sign) && (abs_divisor)) {
env->PSW_USB_V = (((abs_sig_dividend == abs_divisor) &&
(abs_base_dividend >= abs_divisor)) ||
(abs_sig_dividend > abs_divisor));
} else {
env->PSW_USB_V = (abs_sig_dividend >= abs_divisor);
}
/* calc overflow
ofv if (a/b >= 255) <=> (a/255 >= b) */
env->PSW_USB_V = (abs_sig_dividend >= abs_divisor) << 31;
env->PSW_USB_V = env->PSW_USB_V << 31;
env->PSW_USB_SV |= env->PSW_USB_V;
env->PSW_USB_AV = 0;
@ -1992,29 +1982,19 @@ uint64_t helper_dvinit_b_131(CPUTriCoreState *env, uint32_t r1, uint32_t r2)
uint64_t helper_dvinit_h_13(CPUTriCoreState *env, uint32_t r1, uint32_t r2)
{
uint64_t ret;
int32_t abs_sig_dividend, abs_base_dividend, abs_divisor;
int32_t quotient_sign;
int32_t abs_sig_dividend, abs_divisor;
ret = sextract32(r1, 0, 32);
ret = ret << 16;
quotient_sign = 0;
if (!((r1 & 0x80000000) == (r2 & 0x80000000))) {
ret |= 0xffff;
quotient_sign = 1;
}
abs_sig_dividend = abs((int32_t)r1) >> 7;
abs_base_dividend = abs((int32_t)r1) & 0x7f;
abs_sig_dividend = abs((int32_t)r1) >> 16;
abs_divisor = abs((int32_t)r2);
/* calc overflow */
env->PSW_USB_V = 0;
if ((quotient_sign) && (abs_divisor)) {
env->PSW_USB_V = (((abs_sig_dividend == abs_divisor) &&
(abs_base_dividend >= abs_divisor)) ||
(abs_sig_dividend > abs_divisor));
} else {
env->PSW_USB_V = (abs_sig_dividend >= abs_divisor);
}
/* calc overflow
ofv if (a/b >= 0xffff) <=> (a/0xffff >= b) */
env->PSW_USB_V = (abs_sig_dividend >= abs_divisor) << 31;
env->PSW_USB_V = env->PSW_USB_V << 31;
env->PSW_USB_SV |= env->PSW_USB_V;
env->PSW_USB_AV = 0;