Add SVE opaque built-in types

This patch adds the SVE built-in types defined by the Procedure Call
Standard for the Arm Architecture:

   https://developer.arm.com/docs/100986/0000

It handles the types in all relevant places that deal with built-in types.
At the moment, some of these places bail out with an error, including:

   (1) trying to generate LLVM IR for the types
   (2) trying to generate debug info for the types
   (3) trying to mangle the types using the Microsoft C++ ABI
   (4) trying to @encode the types in Objective C

(1) and (2) are fixed by follow-on patches but (unlike this patch)
they deal mostly with target-specific LLVM details, so seemed like
a logically separate change.  There is currently no spec for (3) and
(4), so reporting an error seems like the correct behaviour for now.

The intention is that the types will become sizeless types:

   http://lists.llvm.org/pipermail/cfe-dev/2019-June/062523.html

The main purpose of the sizeless type extension is to diagnose
impossible or dangerous uses of the types, such as any that would
require sizeof to have a meaningful defined value.

Until then, the patch sets the alignments of the types to the values
specified in the link above.  It also sets the sizes of the types to
zero, which is chosen to be consistently wrong and shouldn't affect
correctly-written code (i.e. code that would compile even with the
sizeless type extension).

The patch adds the common subset of functionality needed to test the
sizeless type extension on the one hand and to provide SVE intrinsic
functions on the other.  After this patch, the two pieces of work are
essentially independent.

The patch is based on one by Graham Hunter:

   https://reviews.llvm.org/D59245

Differential Revision: https://reviews.llvm.org/D62960

llvm-svn: 368413

3 files changed, 35 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index f6ee7ee26d4..422fbc1e290 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -697,6 +697,22 @@ llvm::DIType *CGDebugInfo::CreateType(const BuiltinType *BT) {
   case BuiltinType::Id: \
     return getOrCreateStructPtrType("opencl_" #ExtType, Id##Ty);
 #include "clang/Basic/OpenCLExtensionTypes.def"
+  // TODO: real support for SVE types requires more infrastructure
+  // to be added first.  The types have a variable length and are
+  // represented in debug info as types whose length depends on a
+  // target-specific pseudo register.
+#define SVE_TYPE(Name, Id, SingletonId) \
+  case BuiltinType::Id:
+#include "clang/Basic/AArch64SVEACLETypes.def"
+  {
+    unsigned DiagID = CGM.getDiags().getCustomDiagID(
+        DiagnosticsEngine::Error,
+        "cannot yet generate debug info for SVE type '%0'");
+    auto Name = BT->getName(CGM.getContext().getPrintingPolicy());
+    CGM.getDiags().Report(DiagID) << Name;
+    // Return something safe.
+    return CreateType(cast<const BuiltinType>(CGM.getContext().IntTy));
+  }
 
   case BuiltinType::UChar:
   case BuiltinType::Char_U:
diff --git a/clang/lib/CodeGen/CodeGenTypes.cpp b/clang/lib/CodeGen/CodeGenTypes.cpp
index 79b29b3d916..1e42c92d53c 100644
--- a/clang/lib/CodeGen/CodeGenTypes.cpp
+++ b/clang/lib/CodeGen/CodeGenTypes.cpp
@@ -512,6 +512,22 @@ llvm::Type *CodeGenTypes::ConvertType(QualType T) {
       ResultType = CGM.getOpenCLRuntime().convertOpenCLSpecificType(Ty);
       break;
 
+    // TODO: real CodeGen support for SVE types requires more infrastructure
+    // to be added first.  Report an error until then.
+#define SVE_TYPE(Name, Id, SingletonId) case BuiltinType::Id:
+#include "clang/Basic/AArch64SVEACLETypes.def"
+    {
+      unsigned DiagID = CGM.getDiags().getCustomDiagID(
+          DiagnosticsEngine::Error,
+          "cannot yet generate code for SVE type '%0'");
+      auto *BT = cast<BuiltinType>(Ty);
+      auto Name = BT->getName(CGM.getContext().getPrintingPolicy());
+      CGM.getDiags().Report(DiagID) << Name;
+      // Return something safe.
+      ResultType = llvm::IntegerType::get(getLLVMContext(), 32);
+      break;
+    }
+
     case BuiltinType::Dependent:
 #define BUILTIN_TYPE(Id, SingletonId)
 #define PLACEHOLDER_TYPE(Id, SingletonId) \
diff --git a/clang/lib/CodeGen/ItaniumCXXABI.cpp b/clang/lib/CodeGen/ItaniumCXXABI.cpp
index 826d98151d9..29ec2d4b81c 100644
--- a/clang/lib/CodeGen/ItaniumCXXABI.cpp
+++ b/clang/lib/CodeGen/ItaniumCXXABI.cpp
@@ -2860,6 +2860,9 @@ static bool TypeInfoIsInStandardLibrary(const BuiltinType *Ty) {
     case BuiltinType::OCLClkEvent:
     case BuiltinType::OCLQueue:
     case BuiltinType::OCLReserveID:
+#define SVE_TYPE(Name, Id, SingletonId) \
+    case BuiltinType::Id:
+#include "clang/Basic/AArch64SVEACLETypes.def"
     case BuiltinType::ShortAccum:
     case BuiltinType::Accum:
     case BuiltinType::LongAccum: