https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98254
Bug ID: 98254
Summary: Failure to optimize simple pattern for
__builtin_convertvector
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: gabravier at gmail dot com
Target Milestone: ---
typedef int32_t __attribute__((vector_size(16))) v4i32;
typedef int16_t __attribute__((vector_size(8))) v4i16;
v4i32 f(short *a)
{
return (v4i32){a[0], a[1], a[2], a[3]};
}
This can be optimized to `return __builtin_convertvector(*(v4i16 *)a, v4i32);`
(or at least, something very close to that, if aliasing is to be taken into
account). LLVM does this transformation, but GCC does not.
