[LLVMdev] Purpose of -debug-compile in NVPTX backend

[Kai]

Hi!

My general understanding of the debug symbol support is that:

- the backend defines in the XXXMCAsmInfo class if debug information is 
supported (e.g. SupportsDebugInformation = true / false)
- if I don't want to output debug information then I can use the 
(hidden) command line option -disable-debug-info-print (defined in 
DwarfDebug.cpp).

However, in NVPTXMCAsmInfo.cpp I found:

- a new command line option:

bool CompileForDebugging;
static cl::opt<bool, true>
Debug("debug-compile", cl::desc("Compile for debugging"), cl::Hidden,
       cl::location(CompileForDebugging),
       cl::init(false));

- and the assignment

   SupportsDebugInformation = CompileForDebugging;

Isn't this redundant code? If yes then the attached patch should be 
committed. If not then I like to know whats going on here....

Regards
Kai
-------------- next part --------------
diff --git a/lib/Target/NVPTX/MCTargetDesc/NVPTXMCAsmInfo.cpp b/lib/Target/NVPTX/MCTargetDesc/NVPTXMCAsmInfo.cpp
index 1d41665..5e128fe 100644
--- a/lib/Target/NVPTX/MCTargetDesc/NVPTXMCAsmInfo.cpp
+++ b/lib/Target/NVPTX/MCTargetDesc/NVPTXMCAsmInfo.cpp
@@ -17,15 +17,6 @@
 
 using namespace llvm;
 
-bool CompileForDebugging;
-
-// -debug-compile - Command line option to inform opt and llc passes to
-// compile for debugging
-static cl::opt<bool, true>
-Debug("debug-compile", cl::desc("Compile for debugging"), cl::Hidden,
-      cl::location(CompileForDebugging),
-      cl::init(false));
-
 void NVPTXMCAsmInfo::anchor() { }
 
 NVPTXMCAsmInfo::NVPTXMCAsmInfo(const Target &T, const StringRef &TT) {
@@ -46,7 +37,7 @@ NVPTXMCAsmInfo::NVPTXMCAsmInfo(const Target &T, const StringRef &TT) {
   InlineAsmStart = " inline asm";
   InlineAsmEnd = " inline asm";
 
-  SupportsDebugInformation = CompileForDebugging;
+  SupportsDebugInformation = true;
   HasDotTypeDotSizeDirective = false;
 
   Data8bitsDirective = " .b8 ";