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/* { dg-options "-O2" } */
/* { dg-do run } */
/* nvptx backend used to emit lo/ls/hs/hi suffixes on unsigned comparison
insns instead of the more common lt/le/ge/gt, but ptxas and PTX JIT
miscompile 'ls' and 'hi' under some circumstances, such as when the first
source operand expands to a constant memory load, as demonstrated below.
Reported as NVIDIA bug ID 1725195 (tracker is not public). */
/* Define this to observe PTX translation breakage. */
//#define EMIT_BROKEN_ASM 1
/* Or define this to get expected codegen. */
//#define EMIT_WORKING_ASM 1
static __attribute__((noinline,noclone)) int ls(unsigned a)
{
unsigned v;
/* %nctaid.x is always 1 in gcc testing. */
asm ("mov.u32 %0, %%nctaid.x;" : "=r"(v));
#if defined(EMIT_BROKEN_ASM)
asm ("set.u32.ls.u32 %0, %1, %0;" : "+r"(a) : "r"(v));
#elif defined(EMIT_WORKING_ASM)
asm ("set.u32.le.u32 %0, %1, %0;" : "+r"(a) : "r"(v));
#else
a = v <= a ? -1 : 0;
#endif
return a;
}
static __attribute__((noinline,noclone)) int hi(unsigned a)
{
unsigned v;
asm ("mov.u32 %0, %%nctaid.x;" : "=r"(v));
#if defined(EMIT_BROKEN_ASM)
asm ("set.u32.hi.u32 %0, %1, %0;" : "+r"(a) : "r"(v));
#elif defined(EMIT_WORKING_ASM)
asm ("set.u32.gt.u32 %0, %1, %0;" : "+r"(a) : "r"(v));
#else
a = v > a ? -1 : 0;
#endif
return a;
}
int main()
{
int i;
for (i=0; i<3; i++)
if (ls(i) != -(1 <= i) || hi(i) != -(1 > i))
__builtin_abort();
return 0;
}
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