[llvm] [AArch64] Consider runtime mode when deciding to use SVE for fixed-length vectors. (PR #96081)

[Paul Walker via llvm-commits]

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@@ -1,9 +1,8 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
 ; RUN: llc -mattr=+sve -force-streaming-compatible  < %s | FileCheck %s --check-prefixes=CHECK,SVE
 ; RUN: llc -mattr=+sve2 -force-streaming-compatible  < %s | FileCheck %s --check-prefixes=CHECK,SVE2
-; RUN: llc -mattr=+sme -force-streaming-compatible  < %s | FileCheck %s --check-prefixes=CHECK,SVE2
-; FIXME: We shouldn't ever be emitting any SVE instructions when +sme is set but the function is not in streaming mode.
-; RUN: llc -mattr=+sme < %s | FileCheck %s --check-prefixes=NEON-NOSVE
+; RUN: llc -mattr=+sme -force-streaming  < %s | FileCheck %s --check-prefixes=CHECK,SVE2
+; RUN: llc -mattr=+sme -force-streaming-compatible < %s | FileCheck %s --check-prefixes=NONEON-NOSVE
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paulwalker-arm wrote:

"protecting against a condition that was written wrongly in the first place" is the view I took, hence recommending its removal.  Alternative, if you want to be paranoid then all the streaming-mode-fixed-length tests should have the extra RUN line for the same rational.

https://github.com/llvm/llvm-project/pull/96081