[DEBUG_INFO][NVPTX] Generate correct data about variable address class.

Summary:
Added ability to generate correct debug info data about the variable
address class. Currently, for all the locals and globals the default
values are used, ADDR_local_space(6) for locals and ADDR_global_space(5)
for globals. The values are taken from the table in
  https://docs.nvidia.com/cuda/archive/10.0/ptx-writers-guide-to-interoperability/index.html#cuda-specific-dwarf.
  We need to emit correct data for address classes of, at least, shared
  and constant globals. Currently, all these variables are treated by
  the cuda-gdb debugger as the variables in the global address space
  and, thus, it require manual data type casting.

Reviewers: echristo, probinson

Subscribers: jholewinski, aprantl, cfe-commits

Differential Revision: https://reviews.llvm.org/D57162

llvm-svn: 353204

1 files changed, 24 insertions, 0 deletions

diff --git a/clang/lib/Basic/Targets/NVPTX.h b/clang/lib/Basic/Targets/NVPTX.h
index 879402dc039..2cdd37ca1b0 100644
--- a/clang/lib/Basic/Targets/NVPTX.h
+++ b/clang/lib/Basic/Targets/NVPTX.h
@@ -35,6 +35,16 @@ static const unsigned NVPTXAddrSpaceMap[] = {
     3, // cuda_shared
 };
 
+/// The DWARF address class. Taken from
+/// https://docs.nvidia.com/cuda/archive/10.0/ptx-writers-guide-to-interoperability/index.html#cuda-specific-dwarf
+static const int NVPTXDWARFAddrSpaceMap[] = {
+    -1, // Default, opencl_private or opencl_generic - not defined
+    5,  // opencl_global
+    -1,
+    8,  // opencl_local or cuda_shared
+    4,  // opencl_constant or cuda_constant
+};
+
 class LLVM_LIBRARY_VISIBILITY NVPTXTargetInfo : public TargetInfo {
   static const char *const GCCRegNames[];
   static const Builtin::Info BuiltinInfo[];
@@ -124,6 +134,20 @@ public:
     Opts.support("cl_khr_local_int32_extended_atomics");
   }
 
+  /// \returns If a target requires an address within a target specific address
+  /// space \p AddressSpace to be converted in order to be used, then return the
+  /// corresponding target specific DWARF address space.
+  ///
+  /// \returns Otherwise return None and no conversion will be emitted in the
+  /// DWARF.
+  Optional<unsigned>
+  getDWARFAddressSpace(unsigned AddressSpace) const override {
+    if (AddressSpace >= llvm::array_lengthof(NVPTXDWARFAddrSpaceMap) ||
+        NVPTXDWARFAddrSpaceMap[AddressSpace] < 0)
+      return llvm::None;
+    return NVPTXDWARFAddrSpaceMap[AddressSpace];
+  }
+
   CallingConvCheckResult checkCallingConvention(CallingConv CC) const override {
     // CUDA compilations support all of the host's calling conventions.
     //