[compiler-rt] [llvm] [clang] [AArch64][SME] Add support for sme-fa64 (PR #70809)

[Matthew Devereau via cfe-commits]

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@@ -248,8 +250,9 @@ inline constexpr ExtensionInfo Extensions[] = {
     {"simd", AArch64::AEK_SIMD, "+neon", "-neon", FEAT_SIMD, "+fp-armv8,+neon", 100},
     {"sm4", AArch64::AEK_SM4, "+sm4", "-sm4", FEAT_SM4, "+sm4,+fp-armv8,+neon", 60},
     {"sme-f16f16", AArch64::AEK_SMEF16F16, "+sme-f16f16", "-sme-f16f16", FEAT_INIT, "", 0},
-    {"sme-f64f64", AArch64::AEK_SMEF64F64, "+sme-f64f64", "-sme-f64f64", FEAT_SME_F64, "+sme,+sme-f64f64,+bf16", 560},
-    {"sme-i16i64", AArch64::AEK_SMEI16I64, "+sme-i16i64", "-sme-i16i64", FEAT_SME_I64, "+sme,+sme-i16i64,+bf16", 570},
+    {"sme-f64f64", AArch64::AEK_SMEF64F64, "+sme-f64f64", "-sme-f64f64", FEAT_SME_F64,  "+sme,+sme-f64f64,+bf16", 560},
+    {"sme-i16i64", AArch64::AEK_SMEI16I64, "+sme-i16i64", "-sme-i16i64", FEAT_SME_I64,  "+sme,+sme-i16i64,+bf16", 570},
+    {"sme-fa64",   AArch64::AEK_SMEFA64,   "+sme-fa64",   "-sme-fa64",   FEAT_SME_FA64, "+sve2",                  580},
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MDevereau wrote:

Apparently its the Function Multi Versioning priority? I'm not sure how it works but it seems to be tested by `attr-target-version.c` which does not appear to be testing the other SME flags such as F16F16

https://github.com/llvm/llvm-project/pull/70809