[llvm] Use Module level target-abi to assign target features for codegenerated functions. (PR #100833)

[Eric Christopher via llvm-commits]

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@@ -387,6 +388,25 @@ Function *Function::Create(FunctionType *Ty, LinkageTypes Linkage,
   return Create(Ty, Linkage, M.getDataLayout().getProgramAddressSpace(), N, &M);
 }
 
+StringRef Function::getDefaultTargetFeatures(const StringRef TargetABI) {
+  Triple T(getParent()->getTargetTriple());
+  StringRef attr = "";
+  if (T.isRISCV64()) {
+    if (TargetABI.equals_insensitive("lp64d"))
+      attr = "+d";
+    else if (TargetABI.equals_insensitive("lp64f"))
+      attr = "+f";
+    else if (TargetABI.equals_insensitive("lp64q"))
+      attr = "+q";
+  } else if (T.isRISCV32() && TargetABI.contains("ilp32f")) {
+    attr = "+f";
+  } else if (T.isARM() || T.isThumb()) {
+    attr = "+thumb-mode";
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echristo wrote:

Yeah, if the stub function has particular properties on a per target basis that aren't inherited from the calling function the pass should call into the backend for them if possible and merge with the calling function appropriately (ala some of the inlining checks). For the generic case they should probably just inherit (unless I'm missing something specific to the pass here @pcc?)

https://github.com/llvm/llvm-project/pull/100833