Andrew Pinski wrote:
While trying to build the GCC 5 with GCC 5, I ran into an ICE when
building libcpp at -O0. The problem is the C++ front-end was not
folding sizeof(a)/sizeof(a[0]) when passed to a function at -O0. The
C++ front-end keeps around sizeof until the gimplifier and there is no
way to fold the expressions that involve them. So to work around the
issue we need to change __builtin_aarch64_im_lane_boundsi to accept an
extra argument and change the first two arguments to size_t type so we
don't get an extra cast there and do the division inside the compiler
itself.
Also we don't want to cause an ICE on any source code so I changed the
assert to be a sorry if either of the two arguments are not integer
constants.
TBH I think it _is_ appropriate to ICE rather than sorry, or even error, if the
size of the vector or vector elements are non-constant or zero. All the calls to
this __builtin are in gcc-specific headers, and if those are wrong, then the
error is in(ternal to) the compiler. (Of course if the lane index is
non-constant that is a programmer error.) We don't wish to support the
programmer writing direct calls to the builtin him/herself!
--Alan
OK? Bootstrapped and tested on aarch64-linux-gnu with no regressions
and I was able to bootstrap without a modified libcpp.
Thanks,
Andrew Pinski
ChangeLog:
* config/aarch64/aarch64-builtins.c (aarch64_init_simd_builtins):
Change the first argument type to size_type_node and add another
size_type_node.
(aarch64_simd_expand_builtin): Handle the new argument to
AARCH64_SIMD_BUILTIN_LANE_CHECK and don't ICE but rather
print sorry out when the first two arguments are not
integer constants.
* config/aarch64/arm_neon.h (__AARCH64_LANE_CHECK):
Pass the sizeof's directly to __builtin_aarch64_im_lane_boundsi.
testsuite/ChangeLog:
* c-c++-common/torture/aarch64-vect-lane-1.c: New testcase.
