Rename the "__unused" definition for CentOS builds

to pass. The name clashes with several files from
CentOS /usr/include/bits directory.

Change-Id: I6121fab916021503c76195578c8733e1174f21e0

Author: pszymich

IGC/AdaptorOCL/SPIRV/SPIRVInternal.h

@@ -104,10 +104,10 @@ namespace spv {
 using namespace llvm;
 
 namespace kOCLTypeQualifierName {
-  __unused const static char *Const      = "const";
-  __unused const static char *Volatile   = "volatile";
-  __unused const static char *Restrict   = "restrict";
-  __unused const static char *Pipe       = "pipe";
+  __attr_unused const static char *Const      = "const";
+  __attr_unused const static char *Volatile   = "volatile";
+  __attr_unused const static char *Restrict   = "restrict";
+  __attr_unused const static char *Pipe       = "pipe";
 }
 
 template<> inline void

IGC/AdaptorOCL/SPIRV/SPIRVReader.cpp

@@ -104,7 +104,7 @@ isOpenCLKernel(SPIRVFunction *BF) {
    return BF->getModule()->isEntryPoint(ExecutionModelKernel, BF->getId());
 }
 
-__unused static void
+__attr_unused static void
 dumpLLVM(Module *M, const std::string &FName) {
   std::error_code EC;
   raw_fd_ostream FS(FName, EC, sys::fs::F_None);
@@ -3967,7 +3967,7 @@ SPIRVToLLVM::transCompilerOption() {
   return true;
 }
 
-__unused static void dumpSPIRVBC(const char* fname, const char* data, unsigned int size)
+__attr_unused static void dumpSPIRVBC(const char* fname, const char* data, unsigned int size)
 {
     FILE* fp;
     fp = fopen(fname, "wb");

IGC/Compiler/CISACodeGen/AdvCodeMotion.cpp

@@ -77,7 +77,7 @@ namespace {
         }
 
         bool hoistUniform(BasicBlock* Src, BasicBlock* Dst) const;
-        __unused bool hoistMost(bool InvPred, BasicBlock* IfBB,
+        __attr_unused bool hoistMost(bool InvPred, BasicBlock* IfBB,
             BasicBlock* TBB, BasicBlock* FBB, BasicBlock* JBB) const;
         bool hoistMost2(bool InvPred, BasicBlock* IfBB,
             BasicBlock* TBB, BasicBlock* FBB, BasicBlock* JBB) const;

IGC/Compiler/CISACodeGen/CISACodeGen.h

@@ -106,7 +106,7 @@ namespace IGC
 
 #define DECLARE_CISA_OPCODE(opCode, name, visaname) \
     visaname,
-    __unused static ISA_Opcode ConvertOpcode[] =
+    __attr_unused static ISA_Opcode ConvertOpcode[] =
     {
     #include "isaDef.def"
     };

IGC/GenISAIntrinsics/GenIntrinsics.cpp

@@ -59,7 +59,7 @@ ID getIntrinsicForGCCBuiltin(const char *Prefix, const char *BuiltinName);
 
 /// Intrinsic::isOverloaded(ID) - Returns true if the intrinsic can be
 /// overloaded.
-__unused static bool isOverloaded(ID id);
+__attr_unused static bool isOverloaded(ID id);
 
 /// IITDescriptor - This is a type descriptor which explains the type
 /// requirements of an intrinsic.  This is returned by

inc/common/UFO/portable_compiler.h

@@ -46,7 +46,7 @@ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
     #define __thread                        __declspec(thread)
     #define __builtin_popcount              __popcnt
 
-    #define __unused
+    #define __attr_unused
 
 #elif defined(__clang__)
 
@@ -78,8 +78,8 @@ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
     #endif
     #define __popcnt                __builtin_popcount
 
-    #ifndef __unused
-        #define __unused        __attribute__((unused))
+    #ifndef __attr_unused
+        #define __attr_unused        __attribute__((unused))
     #endif
 
 #elif __GNUC__
@@ -113,7 +113,7 @@ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
     #define __debugbreak()      do { asm volatile ("int3;"); } while (0)
     #define __popcnt                __builtin_popcount
 
-    #define __unused            __attribute__((unused))
+    #define __attr_unused            __attribute__((unused))
 
 #else