getMangledTypeStr: clarify how it mangles types, and add tests

"Write a set of tests that show how name mangling is done for overloaded intrinsics."  These happen to use gc.relocates to exercise the codepath in question, but is not a GC specific test.

Patch by: [email protected]
Differential Revision: http://reviews.llvm.org/D6915

llvm-svn: 226056

Author: preames

llvm/lib/IR/Function.cpp

@@ -455,6 +455,10 @@ unsigned Function::lookupIntrinsicID() const {
 /// which can't be confused with it's prefix.  This ensures we don't have
 /// collisions between two unrelated function types. Otherwise, you might
 /// parse ffXX as f(fXX) or f(fX)X.  (X is a placeholder for any other type.)
+/// Manglings of integers, floats, and vectors ('i', 'f', and 'v' prefix in most
+/// cases) fall back to the MVT codepath, where they could be mangled to
+/// 'x86mmx', for example; matching on derived types is not sufficient to mangle
+/// everything.
 static std::string getMangledTypeStr(Type* Ty) {
   std::string Result;
   if (PointerType* PTyp = dyn_cast<PointerType>(Ty)) {

llvm/test/CodeGen/Generic/overloaded-intrinsic-name.ll

@@ -0,0 +1,47 @@
+; RUN: opt -verify -S < %s
+
+; Tests the name mangling performed by the codepath following
+; getMangledTypeStr(). Only tests that code with the various manglings
+; run fine: doesn't actually test the mangling with the type of the
+; arguments. Meant to serve as an example-document on how the user
+; should do name manglings.
+
+; Exercise the most general case, llvm_anyptr_type, using gc.relocate
+; and gc.statepoint. Note that it has nothing to do with gc.*
+; functions specifically: any function that accepts llvm_anyptr_type
+; will serve the purpose.
+
+; function and integer
+define i32* @test_iAny(i32* %v) {
+       %tok = call i32 (i1 ()*, i32, i32, ...)* @llvm.experimental.gc.statepoint.p0f_i1f(i1 ()* @return_i1, i32 0, i32 0, i32 0, i32* %v)
+       %v-new = call i32* @llvm.experimental.gc.relocate.p0i32(i32 %tok, i32 4, i32 4)
+       ret i32* %v-new
+}
+
+; float
+define float* @test_fAny(float* %v) {
+       %tok = call i32 (i1 ()*, i32, i32, ...)* @llvm.experimental.gc.statepoint.p0f_i1f(i1 ()* @return_i1, i32 0, i32 0, i32 0, float* %v)
+       %v-new = call float* @llvm.experimental.gc.relocate.p0f32(i32 %tok, i32 4, i32 4)
+       ret float* %v-new
+}
+
+; array of integers
+define [3 x i32]* @test_aAny([3 x i32]* %v) {
+       %tok = call i32 (i1 ()*, i32, i32, ...)* @llvm.experimental.gc.statepoint.p0f_i1f(i1 ()* @return_i1, i32 0, i32 0, i32 0, [3 x i32]* %v)
+       %v-new = call [3 x i32]* @llvm.experimental.gc.relocate.p0a3i32(i32 %tok, i32 4, i32 4)
+       ret [3 x i32]* %v-new
+}
+
+; vector of integers
+define <3 x i32>* @test_vAny(<3 x i32>* %v) {
+       %tok = call i32 (i1 ()*, i32, i32, ...)* @llvm.experimental.gc.statepoint.p0f_i1f(i1 ()* @return_i1, i32 0, i32 0, i32 0, <3 x i32>* %v)
+       %v-new = call <3 x i32>* @llvm.experimental.gc.relocate.p0v3i32(i32 %tok, i32 4, i32 4)
+       ret <3 x i32>* %v-new
+}
+
+declare zeroext i1 @return_i1()
+declare i32 @llvm.experimental.gc.statepoint.p0f_i1f(i1 ()*, i32, i32, ...)
+declare i32* @llvm.experimental.gc.relocate.p0i32(i32, i32, i32)
+declare float* @llvm.experimental.gc.relocate.p0f32(i32, i32, i32)
+declare [3 x i32]* @llvm.experimental.gc.relocate.p0a3i32(i32, i32, i32)
+declare <3 x i32>* @llvm.experimental.gc.relocate.p0v3i32(i32, i32, i32)