[AMDGPU] Factored PAL metadata handling out into its own class

Summary:
This commit introduces a new AMDGPUPALMetadata class that:
* is inside the AMDGPU target;
* keeps an in-memory representation of PAL metadata;
* provides a method to read the frontend-supplied metadata from LLVM IR;
* provides methods for the asm printer to set metadata items;
* provides methods to write the metadata as a binary blob to put in a
  .note record or as an asm directive;
* provides a method to read the metadata as a binary blob from a .note
  record.

Because llvm-readobj cannot call directly into a target, I had to remove
llvm-readobj's ability to dump PAL metadata, pending a resolution to
https://reviews.llvm.org/D52821

Differential Revision: https://reviews.llvm.org/D57027

Change-Id: I756dc830894fcb6850324cdcfa87c0120eb2cf64
llvm-svn: 356582

1 files changed, 0 insertions, 14 deletions

diff --git a/llvm/lib/Support/AMDGPUMetadata.cpp b/llvm/lib/Support/AMDGPUMetadata.cpp
index 4d5ce34dff3..05717b2f827 100644
--- a/llvm/lib/Support/AMDGPUMetadata.cpp
+++ b/llvm/lib/Support/AMDGPUMetadata.cpp
@@ -218,19 +218,5 @@ std::error_code toString(Metadata HSAMetadata, std::string &String) {
 }
 
 } // end namespace HSAMD
-
-namespace PALMD {
-
-std::error_code toString(const Metadata &PALMetadata, std::string &String) {
-  raw_string_ostream Stream(String);
-  for (auto I = PALMetadata.begin(), E = PALMetadata.end(); I != E; ++I) {
-    Stream << Twine(I == PALMetadata.begin() ? " 0x" : ",0x");
-    Stream << Twine::utohexstr(*I);
-  }
-  Stream.flush();
-  return std::error_code();
-}
-
-} // end namespace PALMD
 } // end namespace AMDGPU
 } // end namespace llvm