https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121028
--- Comment #4 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-15 branch has been updated by Spencer Abson <sab...@gcc.gnu.org>: https://gcc.gnu.org/g:b3da1801bef08c75f69f4376ffa05f1de2591ca8 commit r15-10175-gb3da1801bef08c75f69f4376ffa05f1de2591ca8 Author: Spencer Abson <spencer.ab...@arm.com> Date: Thu Jul 31 14:07:31 2025 +0000 aarch64: Prevent streaming-compatible code from assembler rejection [PR121028] Streaming-compatible functions can be compiled without SME enabled, but need to use "SMSTART SM" and "SMSTOP SM" to temporarily switch into the streaming state of a callee. These switches are conditional on the current mode being opposite to the target mode, so no SME instructions are executed if SME is not available. However, in GAS, "SMSTART SM" and "SMSTOP SM" always require +sme. A call from a streaming-compatible function, compiled without SME enabled, to a non -streaming function will be rejected as: Error: selected processor does not support `smstop sm'.. To work around this, we make use of the .inst directive to insert the literal encodings of "SMSTART SM" and "SMSTOP SM". gcc/ChangeLog: PR target/121028 * config/aarch64/aarch64-sme.md (aarch64_smstart_sm): Use the .inst directive if !TARGET_SME. (aarch64_smstop_sm): Likewise. gcc/testsuite/ChangeLog: PR target/121028 * gcc.target/aarch64/sme/call_sm_switch_1.c: Tell check-function -bodies not to ignore .inst directives, and replace the test for "smstart sm" with one for it's encoding. * gcc.target/aarch64/sme/call_sm_switch_11.c: Likewise. * gcc.target/aarch64/sme/pr121028.c: New test. (cherry picked from commit d52e9ef98bb30872482a46e7a2ec6a20c3ca4a4c)
