[clang] [Clang][AArch64] Change SME attributes for shared/new/preserved state. (PR #76971)

[via cfe-commits]

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@@ -1767,14 +1767,22 @@ static void AddAttributesFromFunctionProtoType(ASTContext &Ctx,
       FPT->isNothrow())
     FuncAttrs.addAttribute(llvm::Attribute::NoUnwind);
 
-  if (FPT->getAArch64SMEAttributes() & FunctionType::SME_PStateSMEnabledMask)
+  unsigned SMEBits = FPT->getAArch64SMEAttributes();
+  if (SMEBits & FunctionType::SME_PStateSMEnabledMask)
     FuncAttrs.addAttribute("aarch64_pstate_sm_enabled");
-  if (FPT->getAArch64SMEAttributes() & FunctionType::SME_PStateSMCompatibleMask)
+  if (SMEBits & FunctionType::SME_PStateSMCompatibleMask)
     FuncAttrs.addAttribute("aarch64_pstate_sm_compatible");
-  if (FPT->getAArch64SMEAttributes() & FunctionType::SME_PStateZASharedMask)
+
+  // ZA
+  if (FunctionType::getArmZAState(SMEBits) == FunctionType::ARM_Preserves)
+    FuncAttrs.addAttribute("aarch64_pstate_za_preserved");
+  if (FunctionType::getArmZAState(SMEBits) == FunctionType::ARM_Out ||
+      FunctionType::getArmZAState(SMEBits) == FunctionType::ARM_InOut)
+    FuncAttrs.addAttribute("aarch64_pstate_za_shared");
+  if (FunctionType::getArmZAState(SMEBits) == FunctionType::ARM_In) {
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rsandifo-arm wrote:

This is also the correct handling for `__arm_preserves("za")`.

https://github.com/llvm/llvm-project/pull/76971