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typedef unsigned long long uint64_t;
void abort (void);
#define BASE 0x1234567812345678ull
#define DEF_BBIT_TAKEN(BRANCH_IF, BIT) \
int bbit_is_taken_##BRANCH_IF##_##BIT (volatile uint64_t *p) \
{ \
int ret; \
asm (".set push \n\t" \
".set noreorder \n\t" \
"bbit" #BRANCH_IF " %1, " #BIT ", 1f \n\t" \
"nop \n\t" \
"li %0, 0 \n\t" \
"b 2f \n\t" \
"nop \n\t" \
"1: \n\t" \
"li %0, 1 \n\t" \
"2: \n\t" \
".set pop" \
: "=r"(ret) : "r"(*p)); \
return ret; \
} \
volatile uint64_t taken_##BRANCH_IF##_##BIT = \
BASE & (~(1ull << BIT)) | ((uint64_t) BRANCH_IF << BIT); \
volatile uint64_t not_taken_##BRANCH_IF##_##BIT = \
BASE & (~(1ull << BIT)) | (((uint64_t) !BRANCH_IF) << BIT);
DEF_BBIT_TAKEN (0, 10);
DEF_BBIT_TAKEN (0, 36);
DEF_BBIT_TAKEN (1, 20);
DEF_BBIT_TAKEN (1, 49);
#define EXPECT(X) if (!(X)) abort ();
main ()
{
EXPECT (bbit_is_taken_0_10 (&taken_0_10));
EXPECT (!bbit_is_taken_0_10 (¬_taken_0_10));
EXPECT (bbit_is_taken_0_36 (&taken_0_36));
EXPECT (!bbit_is_taken_0_36 (¬_taken_0_36));
EXPECT (bbit_is_taken_1_20 (&taken_1_20));
EXPECT (!bbit_is_taken_1_20 (¬_taken_1_20));
EXPECT (bbit_is_taken_1_49 (&taken_1_49));
EXPECT (!bbit_is_taken_1_49 (¬_taken_1_49));
}
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