On 5/1/24 12:44 PM, Patrick O'Neill wrote:
Hi Jeff,
It looks like this patch's gcc.target/riscv/round_64.c testcase doesn't
pass when run with newlib.
So I expected this would ultimately end up being a case where certain
builtins aren't enabled when we're using a newlib based C library and
that's exactly what happens here.
Essentially all the "function_c99_misc" routines are disabled for
simplifications. So we're presented with this in forwprop:
__attribute__((noclone, noinline))
float convert_float_to_float_round (float N)
{
double _1;
double _2;
float _4;
;; basic block 2, loop depth 0, maybe hot
;; prev block 0, next block 1, flags: (NEW, VISITED)
;; pred: ENTRY (FALLTHRU,EXECUTABLE)
_1 = (double) N_3(D);
_2 = round (_1);
_4 = (float) _2;
return _4;
;; succ: EXIT j.c:12:10
}
The test relies on the optimizer to realize that's just roundf and
convert it to:
__attribute__((noclone, noinline))
float convert_float_to_float_round (float N)
{
float _6;
;; basic block 2, loop depth 0, maybe hot
;; prev block 0, next block 1, flags: (NEW, VISITED)
;; pred: ENTRY (FALLTHRU,EXECUTABLE)
_6 = __builtin_roundf (N_3(D));
return _6;
;; succ: EXIT (EXECUTABLE) z.c:12:10
}
Failure to do that conversion will result in different code generation
in the end and thus all those scan-asm failures. Thankfully we have a
preexisting way to deal with this in the testsuite.
It also introduced:
FAIL: gcc.target/riscv/rvv/autovec/unop/math-nearbyint-run-2.c execution
test
on rv32gcv newlib/linux.
I'll have to look at this next, but it could well end up being the same
issue under the hood.
jeff
