[llvm] [VFABI] Improve VFABI unit tests (PR #73907)

[Graham Hunter via llvm-commits]

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@@ -40,61 +38,45 @@ class VFABIParserTest : public ::testing::Test {
   LLVMContext Ctx;
   SMDiagnostic Err;
   std::unique_ptr<Module> M;
-  FunctionType *FTy;
+  FunctionType *ScalarFTy = nullptr;
   FunctionCallee F;
 
 protected:
-  // Referencies to the parser output field.
+  // References to the parser output field.
   ElementCount &VF = Info.Shape.VF;
   VFISAKind &ISA = Info.ISA;
-  SmallVector<VFParameter, 8> &Parameters = Info.Shape.Parameters;
+  SmallVector<VFParameter, 8> &VecFuncParameters = Info.Shape.Parameters;
   std::string &ScalarName = Info.ScalarName;
   std::string &VectorName = Info.VectorName;
-  // Invoke the parser. We need to make sure that a function exist in
-  // the module because the parser fails if such function don't
-  // exists. Every time this method is invoked the state of the test
-  // is reset.
-  //
-  // \p MangledName -> the string the parser has to demangle.
-  //
-  // \p VectorName -> optional vector name that the method needs to
-  // use to create the function in the module if it differs from the
-  // standard mangled name.
-  //
-  // \p IRType -> FunctionType string to be used for the signature of
-  // the vector function.  The correct signature is needed by the
-  // parser only for scalable functions. For the sake of testing, the
-  // generic fixed-length case can use as signature `void()`.
-  //
+
+  /// Invoke the parser. We need to make sure that a function exist in the
+  /// module because the parser fails if such function don't exists. Every time
+  /// this method is invoked the state of the test is reset.
+  ///
+  /// \p MangledName string the parser has to demangle.
+  ///
+  /// \p ScalarFTyStr FunctionType string to be used to get the signature of
+  /// the Scalar function. Used by `tryDemangleForVFABI` to check for the number
+  // of arguments on Scalable vectors, and by `matchScalarParamNum` to perform
+  /// some additional checking in the tests in this file.
   bool invokeParser(const StringRef MangledName,
-                    const StringRef ScalarName = "",
-                    const StringRef IRType = "void()") {
-    StringRef Name = MangledName;
-    if (!ScalarName.empty())
-      Name = ScalarName;
-    // Reset the VFInfo and the Module to be able to invoke
-    // `invokeParser` multiple times in the same test.
-    reset(Name, IRType);
+                    const StringRef ScalarFTyStr = "void()") {
+    // Reset the VFInfo and the Module to be able to invoke `invokeParser`
+    // multiple times in the same test.
+    reset(ScalarFTyStr);
 
     // Fake the arguments to the CallInst.
-    SmallVector<Value *> Args;
-    for (Type *ParamTy : FTy->params()) {
-      Args.push_back(Constant::getNullValue(ParamTy->getScalarType()));
-    }
-    std::unique_ptr<CallInst> CI(CallInst::Create(F, Args));
-    const auto OptInfo = VFABI::tryDemangleForVFABI(MangledName, *(CI.get()));
+    const auto OptInfo = VFABI::tryDemangleForVFABI(MangledName, ScalarFTy);
     if (OptInfo) {
       Info = *OptInfo;
       return true;
     }
-
     return false;
   }
 
   // Checks that 1. the last Parameter in the Shape is of type
----------------
huntergr-arm wrote:

I think that's a single mask which uses one or more vector registers depending on the datatypes and VF; if it takes more than one register to express, then it would be considered to be multiple parameters from a calling convention point of view even though its a single mask.

https://github.com/llvm/llvm-project/pull/73907