haraldwolff/qemu-patch-raspberry4
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target-alpha: overflow condition for sublv and subqv

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The conditions to detect overflow in sub operations was wrong.

This patch is necessary to boot Tru64.

Signed-off-by: Tristan Gingold <gingold@adacore.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7073 c046a42c-6fe2-441c-8c8c-71466251a162
This commit is contained in:
aurel32 2009-04-10 21:27:15 +00:00
parent 68238a9e90
commit ecbb5ea104
3 changed files with 40 additions and 8 deletions
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16
target-alpha/op_helper.c
View file

@ -158,22 +158,22 @@ uint64_t helper_addlv (uint64_t op1, uint64_t op2)
uint64_t helper_subqv (uint64_t op1, uint64_t op2)
{
uint64_t tmp = op1;
op1 -= op2;
if (unlikely(((~tmp) ^ op1 ^ (-1ULL)) & ((~tmp) ^ op2) & (1ULL << 63))) {
uint64_t res;
res = op1 - op2;
if (unlikely((op1 ^ op2) & (res ^ op1) & (1ULL << 63))) {
helper_excp(EXCP_ARITH, EXCP_ARITH_OVERFLOW);
}
return op1;
return res;
}
uint64_t helper_sublv (uint64_t op1, uint64_t op2)
{
uint64_t tmp = op1;
op1 = (uint32_t)(op1 - op2);
if (unlikely(((~tmp) ^ op1 ^ (-1UL)) & ((~tmp) ^ op2) & (1UL << 31))) {
uint32_t res;
res = op1 - op2;
if (unlikely((op1 ^ op2) & (res ^ op1) & (1UL << 31))) {
helper_excp(EXCP_ARITH, EXCP_ARITH_OVERFLOW);
}
return op1;
return res;
}
uint64_t helper_mullv (uint64_t op1, uint64_t op2)

3
tests/alpha/Makefile
View file

@ -23,6 +23,9 @@ test-cmov.o: test-cond.c
test-cmov: test-cmov.o crt.o
$(LINK)
test-ovf: test-ovf.o crt.o
$(LINK)
check: $(TESTS)
for f in $(TESTS); do $(SIM) $$f || exit 1; done

29
tests/alpha/test-ovf.c Normal file
View file

@ -0,0 +1,29 @@
static long test_subqv (long a, long b)
{
long res;
asm ("subq/v %1,%2,%0"
: "=r" (res) : "r" (a), "r" (b));
return res;
}
static struct {
long (*func)(long, long);
long a;
long b;
long r;
} vectors[] =
{
{test_subqv, 0, 0x7d54000, 0xfffffffff82ac000L}
};
int main (void)
{
int i;
for (i = 0; i < sizeof (vectors)/sizeof(vectors[0]); i++)
if ((*vectors[i].func)(vectors[i].a, vectors[i].b) != vectors[i].r) {
write(1, "Failed\n", 7);
}
write(1, "OK\n", 3);
return 0;
}