[llvm] Extend MemoryEffects to Support Target-Specific Memory Locations (PR #148650)

[Paul Walker via llvm-commits]

================
@@ -0,0 +1,48 @@
+// RUN: llvm-tblgen -gen-intrinsic-impl -I %p/../../include -DTEST_INTRINSICS_SUPPRESS_DEFS %s | FileCheck %s
+
+include "llvm/IR/Intrinsics.td"
+
+def int_aarch64_set_target_mem0   : DefaultAttrsIntrinsic<[], [llvm_i64_ty], [IntrInaccessibleWriteMemOnly<TargetMem0>]>;
+
+def int_aarch64_get_target_mem1   : DefaultAttrsIntrinsic<[], [llvm_i64_ty], [IntrInaccessibleReadMemOnly<TargetMem1>]>;
+
+def int_aarch64_get_target_mem0_set_target_mem1   : DefaultAttrsIntrinsic<[], [llvm_i64_ty], [IntrInaccessibleReadMemOnly<TargetMem0>, IntrInaccessibleWriteMemOnly<TargetMem1>]>;
+
+// CHECK:    static constexpr unsigned IntrinsicNameOffsetTable[] = {
+// CHECK-NEXT:  1, // not_intrinsic
+// CHECK-NEXT:  15, // llvm.aarch64.get.target.mem0.set.target.mem1
+// CHECK-NEXT:  60, // llvm.aarch64.get.target.mem1
+// CHECK-NEXT:  89, // llvm.aarch64.set.target.mem0
+
+// CHECK:   static AttributeSet getIntrinsicFnAttributeSet(LLVMContext &C, unsigned ID) {
+// CHECK-NEXT:  switch (ID) {
+// CHECK-NEXT:    default: llvm_unreachable("Invalid attribute set number");
+// CHECK-NEXT:  case 0:
+// CHECK-NEXT:    return AttributeSet::get(C, {
+// CHECK-NEXT:      Attribute::get(C, Attribute::NoUnwind),
+// CHECK-NEXT:      Attribute::get(C, Attribute::NoCallback),
+// CHECK-NEXT:      Attribute::get(C, Attribute::NoSync),
+// CHECK-NEXT:      Attribute::get(C, Attribute::NoFree),
+// CHECK-NEXT:      Attribute::get(C, Attribute::WillReturn),
+// CHECK-NEXT:      // ArgMem: NoModRef, InaccessibleMem: NoModRef, ErrnoMem: NoModRef, Other: NoModRef, TargetMem0: Ref, TargetMem1: Mod
----------------
paulwalker-arm wrote:

FYI: This tripped me up where I thought the output was wrong because it's in reverse order to the order in which the intrinsics are defined.  If you agree there's value then here's a small patch that emits the intrinsic name after the case statement, which makes it clear which intrinsic the code applies to.
```
--- a/llvm/utils/TableGen/Basic/IntrinsicEmitter.cpp
+++ b/llvm/utils/TableGen/Basic/IntrinsicEmitter.cpp
@@ -574,10 +574,10 @@ static AttributeSet getIntrinsicFnAttributeSet(LLVMContext &C, unsigned ID) {
     if (!UniqFnAttributes.try_emplace(&Int, ID).second)
       continue;
     OS << formatv(R"(
-  case {}:
+  case {}: // {}
     return AttributeSet::get(C, {{
 )",
-                  ID);
+                  ID, Int.Name);
     auto addAttribute = [&OS](StringRef Attr) {
       OS << formatv("      Attribute::get(C, Attribute::{}),\n", Attr);
     };
```

https://github.com/llvm/llvm-project/pull/148650