Kito,
Thanks for the reality-check: the subreg-expressions are getting in the way.
I'll drop this from v2, as a permanent resolution for this will be a
bit more involved.
Philipp.
On Thu, 11 Nov 2021 at 17:42, Kito Cheng wrote:
>
> Hi Philipp:
>
> This testcase got wrong result with this patch
Hi Philipp:
This testcase got wrong result with this patch even w/o
si3_sext pattern:
#include
#define MAX(A, B) ((A) > (B) ? (A) : (B))
long long __attribute__((noinline, noipa))
foo6(long long a, long long b, int c)
{
int xa = a;
int xb = b;
return MAX(MAX(xa, xb), c);
}
int main() {
IIRC it's not work even without sign extend pattern since I did similar
experimental before (not for RISC-V, but same concept), I guess I need more
time to test that.
Philipp Tomsich 於 2021年11月12日 週五 00:18 寫道：
> Kito,
>
> Unless I am missing something, the problem is not the relaxation to
> GPR,
Kito,
Unless I am missing something, the problem is not the relaxation to
GPR, but rather the sign-extending pattern I had squashed into the
same patch.
If you disable "si3_sext", a sext.w will be have to be
emitted after the 'max' and before the return (or before the SImode
output is consumed as
Hi Philipp:
We can't pretend we have SImode min/max instruction without that semantic.
Give this testcase, x86 and rv64gc print out 8589934592 8589934591 = 0,
but with this patch and compile with rv64gc_zba_zbb -O3, the output
become 8589934592 8589934591 = 8589934592
-Testcase---
