llvm-project/llvm/lib/Transforms
Adrian Prantl 565cc18d8f Reapply: Teach SROA how to update debug info for fragmented variables.
This reapplies r225379.

ChangeLog:
- The assertion that this commit previously ran into about the inability
  to handle indirect variables has since been removed and the backend
  can handle this now.
- Testcases were upgrade to the new MDLocation format.
- Instead of keeping a DebugDeclares map, we now use
  llvm::FindAllocaDbgDeclare().

Original commit message follows.

Debug info: Teach SROA how to update debug info for fragmented variables.
This allows us to generate debug info for extremely advanced code such as

 typedef struct { long int a; int b;} S;

 int foo(S s) {
   return s.b;
 }

which at -O1 on x86_64 is codegen'd into

 define i32 @foo(i64 %s.coerce0, i32 %s.coerce1) #0 {
   ret i32 %s.coerce1, !dbg !24
 }

with this patch we emit the following debug info for this

 TAG_formal_parameter [3]
   AT_location( 0x00000000
                0x0000000000000000 - 0x0000000000000006: rdi, piece 0x00000008, rsi, piece 0x00000004
                0x0000000000000006 - 0x0000000000000008: rdi, piece 0x00000008, rax, piece 0x00000004 )
                AT_name( "s" )
                AT_decl_file( "/Volumes/Data/llvm/_build.ninja.release/test.c" )

Thanks to chandlerc, dblaikie, and echristo for their feedback on all
previous iterations of this patch!

llvm-svn: 226598
2015-01-20 19:42:22 +00:00
..
Hello [CMake] Add LLVM_LINK_COMPONENTS to loadable modules, LLVMHello and BugpointPasses, on Win32. 2014-07-13 13:36:48 +00:00
IPO [PM] Lift the analyses into the interface for 2015-01-19 03:03:39 +00:00
InstCombine [PM] Clean up a bunch of the doxygen / API docs on the InstCombiner pass 2015-01-20 19:27:58 +00:00
Instrumentation [msan] Optimize -msan-check-constant-shadow. 2015-01-20 15:21:35 +00:00
ObjCARC IR: Split Metadata from Value 2014-12-09 18:38:53 +00:00
Scalar Reapply: Teach SROA how to update debug info for fragmented variables. 2015-01-20 19:42:22 +00:00
Utils IR: Move MDNode clone() methods from ValueMapper to MDNode, NFC 2015-01-20 02:56:57 +00:00
Vectorize Fix Operandreorder logic in SLPVectorizer to generate longer vectorizable chain. 2015-01-20 06:11:00 +00:00
CMakeLists.txt Extracted ObjCARC.cpp into its own library libLLVMObjCARCOpts in preparation for refactoring the ARC Optimizer. 2013-01-28 01:35:51 +00:00
LLVMBuild.txt Extracted ObjCARC.cpp into its own library libLLVMObjCARCOpts in preparation for refactoring the ARC Optimizer. 2013-01-28 01:35:51 +00:00
Makefile Extracted ObjCARC.cpp into its own library libLLVMObjCARCOpts in preparation for refactoring the ARC Optimizer. 2013-01-28 01:35:51 +00:00