Displaying 2 results from an estimated 2 matches for "previousdef".
2020 Apr 16
2
Need help figuring out a isNopCopy() assert
I'm trying to fix a bug in the PowerPC SPE backend that prevents a
bunch of FreeBSD ports from building, including gtk20. The attached
file, generated from the following C source, triggers the "Def ==
PreviousDef" assertion in isNopCopy():
typedef float a;
typedef struct {
a b, c;
} complex;
d(complex *e, complex *h) {
double f = h->c, g = h->b;
i(g);
e->c = g * j(f);
}
This was a reduction from texlive's c_cos.c.
The applicable assertion failure is:
Assertion failed: (Def == P...
2017 Sep 18
1
Resend: assertion in MachineCopyPropagation::isNopCopy
Hi, anyone know anything about copy propagation? Matthias, I see this
was your code originally? Was there some assumptions you made?
I'm hitting an assertion in MachineCopyPropagation::isNopCopy:
if (Src == PreviousSrc) {
assert(Def == PreviousDef);
return true;
}
This code compares two COPY instruction to see whether they are
effectively "the same". The assert assumes that, if the sources are the
same register then the destinations must be as well.
My instructions look like this, however:
%V2<def> = COPY %V6
%V6...