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5f0303833d
Various 32-bit targets show failures in gcc.dg/analyzer/data-model-1.c
with tests of the form:
__analyzer_eval (q[-2].x == 107024); /* { dg-warning "TRUE" } */
__analyzer_eval (q[-2].y == 107025); /* { dg-warning "TRUE" } */
where they emit UNKNOWN instead.
The root cause is that gimple has a byte-based twos-complement offset
of -16 expressed like this:
_55 = q_92 + 4294967280; (32-bit)
or:
_55 = q_92 + 18446744073709551600; (64-bit)
Within region_model::convert_byte_offset_to_array_index that unsigned
offset was being divided by the element size to get an offset within
an array.
This happened to work on 64-bit target and host, but not elsewhere;
the offset needs to be converted to a signed type before the division
is meaningful.
This patch does so, fixing the failures.
gcc/analyzer/ChangeLog:
PR analyzer/93281
* region-model.cc
(region_model::convert_byte_offset_to_array_index): Convert to
ssizetype before dividing by byte_size. Use fold_binary rather
than fold_build2 to avoid needlessly constructing a tree for the
non-const case.
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