[llvm] [LLVM][SME] Only FADD/FSUB are enabled by either sme-f16f16 or sme-f8f16. (PR #145704)

[Paul Walker via llvm-commits]

https://github.com/paulwalker-arm created https://github.com/llvm/llvm-project/pull/145704

Whilst not technically NFC, there are no test failures so we are not relying on the broken behaviour.

>From 5295967a0779c11354d0f6c08dea78a343d33a4c Mon Sep 17 00:00:00 2001
From: Paul Walker <paul.walker at arm.com>
Date: Wed, 25 Jun 2025 13:56:59 +0000
Subject: [PATCH] [LLVM][SME] Only FADD/FSUB are enabled by either sme-f16f16
 or sme-f8f16.

---
 llvm/lib/Target/AArch64/AArch64SMEInstrInfo.td | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/llvm/lib/Target/AArch64/AArch64SMEInstrInfo.td b/llvm/lib/Target/AArch64/AArch64SMEInstrInfo.td
index 61abc3c3c479a..db27ca978980f 100644
--- a/llvm/lib/Target/AArch64/AArch64SMEInstrInfo.td
+++ b/llvm/lib/Target/AArch64/AArch64SMEInstrInfo.td
@@ -915,7 +915,9 @@ defm FADD_VG2_M2Z_H : sme2_multivec_accum_add_sub_vg2<"fadd", 0b0100, MatrixOp16
 defm FADD_VG4_M4Z_H : sme2_multivec_accum_add_sub_vg4<"fadd", 0b0100, MatrixOp16, ZZZZ_h_mul_r, nxv8f16,  int_aarch64_sme_add_za16_vg1x4>;
 defm FSUB_VG2_M2Z_H : sme2_multivec_accum_add_sub_vg2<"fsub", 0b0101, MatrixOp16, ZZ_h_mul_r, nxv8f16,  int_aarch64_sme_sub_za16_vg1x2>;
 defm FSUB_VG4_M4Z_H : sme2_multivec_accum_add_sub_vg4<"fsub", 0b0101, MatrixOp16, ZZZZ_h_mul_r, nxv8f16,  int_aarch64_sme_sub_za16_vg1x4>;
+}
 
+let Predicates = [HasSMEF16F16] in {
 defm FMLA_VG2_M2ZZI_H : sme2p1_multi_vec_array_vg2_index_16b<"fmla", 0b00, 0b100, ZZ_h_mul_r, ZPR4b16, nxv8f16, int_aarch64_sme_fmla_lane_vg1x2>;
 defm FMLA_VG4_M4ZZI_H : sme2p1_multi_vec_array_vg4_index_16b<"fmla", 0b000, ZZZZ_h_mul_r, ZPR4b16, nxv8f16, int_aarch64_sme_fmla_lane_vg1x4>;
 defm FMLA_VG2_M2ZZ_H :  sme2_dot_mla_add_sub_array_vg2_single<"fmla", 0b0011100, MatrixOp16, ZZ_h, ZPR4b16, nxv8f16, int_aarch64_sme_fmla_single_vg1x2>;