[llvm] [AArch64][SME] Fix frame lowering not using a base pointer for SME functions. (PR #91643)

[Eli Friedman via llvm-commits]

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@@ -0,0 +1,28 @@
+# RUN: llc -mtriple=aarch64-none-linux-gnu -run-pass=prologepilog -mattr=+sme %s -o - | FileCheck %s --check-prefix=SME
+--- |
+    define void @hasBasepointer_sme_streaming() "aarch64_pstate_sm_enabled" { ret void }
+...
+---
+# This test verifies that the basepointer is available in presence of SME stack objects.
+# This is almost identical to the SVE version of this test but has to be a separate file
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efriedma-quic wrote:

Can you just mark the target attribute on the IR function, instead of using -mattr?  Not a big deal either way.

https://github.com/llvm/llvm-project/pull/91643