aarch64: Don't return invalid GIMPLE assign statements

aarch64_general_gimple_fold_builtin doesn't check whether the LHS of a
function call is null before converting it to an assign statement. To avoid
returning an invalid GIMPLE statement in this case, we instead assign the
expression result to a new (unused) variable.

This change only affects code that:
1) Calls an intrinsic function that has no side effects;
2) Does not use or store the value returned by the intrinsic;
3) Uses parameters that prevent the front-end eliminating the call prior to
gimplification.

The ICE is unlikely to have occurred in the wild, as it relies on the presence
of a redundant intrinsic call.

gcc/ChangeLog:

	* config/aarch64/aarch64-builtins.cc
	(aarch64_general_gimple_fold_builtin): Add fixup for invalid GIMPLE.

gcc/testsuite/ChangeLog:

	* gcc.target/aarch64/advsimd-intrinsics/ignored_return_1.c: New test.

0 files changed, 0 insertions, 0 deletions