[llvm] Enhance TLI detection of __size_returning_new lib funcs. (PR #102391)

[Snehasish Kumar via llvm-commits]

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@@ -1049,6 +1049,50 @@ static bool matchType(FuncArgTypeID ArgTy, const Type *Ty, unsigned IntBits,
   llvm_unreachable("Invalid type");
 }
 
+static bool isValidProtoForSizeReturningNew(const FunctionType &FTy, LibFunc F,
+                                            const Module &M,
+                                            int SizeTSizeBits) {
+  switch (F) {
+  case LibFunc_size_returning_new: {
+    if (FTy.getNumParams() != 1 ||
+        !FTy.getParamType(0)->isIntegerTy(SizeTSizeBits)) {
+      return false;
+    }
+  } break;
+  case LibFunc_size_returning_new_hot_cold: {
+    if (FTy.getNumParams() != 2 ||
+        !FTy.getParamType(0)->isIntegerTy(SizeTSizeBits) ||
+        !FTy.getParamType(1)->isIntegerTy(8)) {
+      return false;
+    }
+  } break;
+  case LibFunc_size_returning_new_aligned: {
+    if (FTy.getNumParams() != 2 ||
+        !FTy.getParamType(0)->isIntegerTy(SizeTSizeBits) ||
+        !FTy.getParamType(1)->isIntegerTy(SizeTSizeBits)) {
+      return false;
+    }
+  } break;
+  case LibFunc_size_returning_new_aligned_hot_cold:
+    if (FTy.getNumParams() != 3 ||
+        !FTy.getParamType(0)->isIntegerTy(SizeTSizeBits) ||
+        !FTy.getParamType(1)->isIntegerTy(SizeTSizeBits) ||
+        !FTy.getParamType(2)->isIntegerTy(8)) {
+      return false;
+    }
+    break;
+  default:
+    return false;
+  }
+
+  auto &Context = M.getContext();
+  llvm::Type *I8Ty = Type::getInt8Ty(Context);
+  llvm::PointerType *I8PtrTy = PointerType::get(I8Ty, 0);
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snehasish wrote:

Done.

https://github.com/llvm/llvm-project/pull/102391