GPU: Add GPUCA_RTC_CONSTEXPR macro for constexpr only in RTC

Author: davidrohr

GPU/Common/GPUCommonDef.h

@@ -72,6 +72,10 @@
   #define GPUCA_RTC_SPECIAL_CODE(...)
 #endif
 
+#ifndef GPUCA_RTC_CONSTEXPR
+  #define GPUCA_RTC_CONSTEXPR
+#endif
+
 #ifndef GPUCA_DETERMINISTIC_CODE
   #ifdef GPUCA_DETERMINISTIC_MODE
     #define GPUCA_DETERMINISTIC_CODE(det, indet) det // In deterministic mode, take deterministic code path

GPU/GPUTracking/Base/cuda/GPUReconstructionCUDAGenRTC.cxx

@@ -38,6 +38,7 @@ int32_t GPUReconstructionCUDA::genRTC(std::string& filename, uint32_t& nCompile)
 {
   std::string rtcparam = std::string("#define GPUCA_RTC_CODE\n") +
                          std::string(GetProcessingSettings().rtc.optSpecialCode ? "#define GPUCA_RTC_SPECIAL_CODE(...) __VA_ARGS__\n" : "#define GPUCA_RTC_SPECIAL_CODE(...)\n") +
+                         std::string(GetProcessingSettings().rtc.optConstexpr ? "#define GPUCA_RTC_CONSTEXPR constexpr\n" : "#define GPUCA_RTC_CONSTEXPR\n") +
                          GPUParamRTC::generateRTCCode(param(), GetProcessingSettings().rtc.optConstexpr);
   if (filename == "") {
     filename = "/tmp/o2cagpu_rtc_";

GPU/GPUTracking/Base/cuda/GPUReconstructionCUDArtc.cu

@@ -18,6 +18,7 @@
 // Keep some preprocessor calls unprocessed
 #define GPUCA_RTC_SPECIAL_CODE(...) GPUCA_RTC_SPECIAL_CODE(__VA_ARGS__)
 #define GPUCA_DETERMINISTIC_CODE(...) GPUCA_DETERMINISTIC_CODE(__VA_ARGS__)
+#define GPUCA_RTC_CONSTEXPR GPUCA_RTC_CONSTEXPR
 
 // GPUReconstructionCUDAIncludesSystem.h prependended by CMakewithout preprocessor running
 #include "GPUReconstructionCUDADef.h"