[Comgr] Turn DEVICE_LIBS_ID into an unsigned char

`char` may be signed or unsigned depending on the platfrom.
Using `unsigned char` guarantees consistency across all the platforms,
plus it doesn't need conversion from the digest() python method).

Author: jmmartinez

amd/comgr/cmake/device-libs-id.py

@@ -15,6 +15,5 @@
     for x in args.headers:
         hash.update(open(x, 'rb').read())
     digest_uchar = hash.digest()
-    digest_char = [e if e < 128 else e-256 for e in digest_uchar]
-    digest_elts = ", ".join(map(str, digest_char))
-    print(f"static const char {args.varname}[] = {{{digest_elts}, 0}};", file=open(args.output, 'w'))
+    digest_elts = ", ".join(map(str, digest_uchar))
+    print(f"static const unsigned char {args.varname}[] = {{{digest_elts}, 0}};", file=open(args.output, 'w'))

amd/comgr/src/comgr-cache-command.cpp

@@ -87,7 +87,7 @@ CachedCommandAdaptor::getIdentifier() const {
   H.update(env::shouldEmitVerboseLogs());
   addString(H, getClangFullVersion());
   addString(H, getComgrHashIdentifier());
-  addString(H, getDeviceLibrariesIdentifier());
+  H.update(getDeviceLibrariesIdentifier());
 
   if (Error E = addInputIdentifier(H))
     return E;

amd/comgr/src/comgr-device-libs.cpp

@@ -66,7 +66,7 @@ amd_comgr_status_t addObject(DataSet *DataSet, amd_comgr_data_kind_t Kind,
 #include "opencl2.0-c.inc"
 } // namespace
 
-StringRef getDeviceLibrariesIdentifier() { return DEVICE_LIBS_ID; }
+ArrayRef<unsigned char> getDeviceLibrariesIdentifier() { return DEVICE_LIBS_ID; }
 
 amd_comgr_status_t addPrecompiledHeaders(DataAction *ActionInfo,
                                          DataSet *ResultSet) {

amd/comgr/src/comgr-device-libs.h

@@ -49,7 +49,7 @@ struct DataSet;
 amd_comgr_status_t addPrecompiledHeaders(DataAction *ActionInfo,
                                          DataSet *ResultSet);
 
-llvm::StringRef getDeviceLibrariesIdentifier();
+llvm::ArrayRef<unsigned char> getDeviceLibrariesIdentifier();
 
 llvm::ArrayRef<std::tuple<llvm::StringRef, llvm::StringRef>>
 getDeviceLibraries();