[llvm] [clang] [Clang][SME] Detect always_inline used with mismatched streaming attributes (PR #77936)

[Sam Tebbs via cfe-commits]

================
@@ -812,6 +819,24 @@ Address AArch64ABIInfo::EmitMSVAArg(CodeGenFunction &CGF, Address VAListAddr,
                           /*allowHigherAlign*/ false);
 }
 
+void AArch64TargetCodeGenInfo::checkFunctionCallABI(
+    CodeGenModule &CGM, SourceLocation CallLoc, const FunctionDecl *Caller,
+    const FunctionDecl *Callee, const CallArgList &Args) const {
+  if (!Callee->hasAttr<AlwaysInlineAttr>())
+    return;
+
+  auto CalleeStreamingMode = Sema::getArmStreamingFnType(Callee);
+  auto CallerStreamingMode = Sema::getArmStreamingFnType(Caller);
+
+  // The caller can inline the callee if their streaming modes match or the
+  // callee is streaming compatible
+  if (CalleeStreamingMode != CallerStreamingMode &&
----------------
SamTebbs33 wrote:

It is indeed valid to inline a streaming function into a locally streaming function since at the inline point streaming is guaranteed to be on. We don't need the streaming mode save and restore that would come from a locally streaming function's prologue and epilogue.

https://github.com/llvm/llvm-project/pull/77936