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260 Commits

Author SHA1 Message Date
Kevin Enderby e7739d484f The second part of support for generating dwarf for assembly source files. This 
generates the dwarf Compile Unit DIE and a dwarf subprogram DIE for each
non-temporary label.

The next part will be to get the clang driver to enable this when assembling
a .s file.  rdar://9275556

llvm-svn: 146262
 2011-12-09 18:09:40 +00:00
Bill Wendling efdd2f8fef Re-enable compact unwind. It seems to work now. <rdar://problem/10441838> 
llvm-svn: 145977
 2011-12-06 22:18:12 +00:00
Bob Wilson 8d1c7dbdff Disable generation of compact unwind encodings. <rdar://problem/10441578> 
This still seems to be causing some failures.  It needs more testing before
it gets enabled again.

llvm-svn: 144543
 2011-11-14 18:21:07 +00:00
Bob Wilson c391f7ff64 Remove FIXME comment that should have been removed with r144351. 
llvm-svn: 144392
 2011-11-11 17:34:14 +00:00
Bill Wendling 70976ad9c2 Reenable compact unwinding now that <rdar://problem/10430076> is fixed. 
llvm-svn: 144351
 2011-11-11 01:03:50 +00:00
Bill Wendling f311655e3f Disable compact unwind generation until I can solve the codegen problems. 
llvm-svn: 144346
 2011-11-11 00:28:42 +00:00
Benjamin Kramer 6312682b46 Simplify code. No functionality change. 
llvm-svn: 144186
 2011-11-09 13:19:15 +00:00
Bill Wendling 39674fc008 Emit the compact unwind *if* we have a compact unwind encoding. 
*headdesk*

llvm-svn: 144138
 2011-11-08 22:23:43 +00:00
Benjamin Kramer 69d57cf9c4 Simplify some uses of utohexstr. 
As a side effect hex is printed lowercase instead of uppercase now.

llvm-svn: 144013
 2011-11-07 21:00:59 +00:00
Bill Wendling 9803abb788 As a first step, emit both the compact unwind and CIE/FDEs for a function. 
llvm-svn: 139152
 2011-09-06 18:37:11 +00:00
Evan Cheng eee864520c Some autoconf tests use module level inline asm to test compiler's handling of 
.cfi_startproc. e.g. libffi:

 $ cat confopt.c 
asm (".cfi_startproc\n\t.cfi_endproc");

int main () { return 0; }

Teach MC / dwarf emission to handle these cfi directives which essentially
create an empty frame.

rdar://10017184

llvm-svn: 138504
 2011-08-24 22:31:37 +00:00
Bill Wendling 4d9aa512f8 Emit the __compact_unwind section first. If there are any frames which weren't 
emitted, emit them next as CIE/FDEs.

llvm-svn: 135807
 2011-07-22 21:18:59 +00:00
Evan Cheng bbf3b0de8b Goodbye TargetAsmInfo. This eliminate last bit of CodeGen and Target in llvm-mc. 
There is still a bit more refactoring left to do in Targets. But we are now very
close to fixing all the layering issues in MC.

llvm-svn: 135611
 2011-07-20 19:50:42 +00:00
Evan Cheng 76792992d6 Add MCObjectFileInfo and sink the MCSections initialization code from 
TargetLoweringObjectFileImpl down to MCObjectFileInfo.

TargetAsmInfo is done to one last method. It's *almost* gone!

llvm-svn: 135569
 2011-07-20 05:58:47 +00:00
Bill Wendling ada366c691 Micro-opt: Only emit compact unwind if there is a compact unwind encoding to emit. 
llvm-svn: 135452
 2011-07-19 00:09:25 +00:00
Bill Wendling 49bc680bdf Use the CompactUnwindEncoding from the Frame, if it's defined. 
llvm-svn: 135451
 2011-07-19 00:06:12 +00:00
Evan Cheng 67c033e6b8 Move getInitialFrameState from TargetFrameInfo to MCAsmInfo (suggestions for 
better location welcome).

llvm-svn: 135438
 2011-07-18 22:29:13 +00:00
Evan Cheng d60fa58ba1 Sink getDwarfRegNum, getLLVMRegNum, getSEHRegNum from TargetRegisterInfo down 
to MCRegisterInfo. Also initialize the mapping at construction time.

This patch eliminate TargetRegisterInfo from TargetAsmInfo. It's another step
towards fixing the layering violation.

llvm-svn: 135424
 2011-07-18 20:57:22 +00:00
Evan Cheng a83b37a9db Move some parts of TargetAsmInfo down to MCAsmInfo. This is not the greatest 
solution but it is a small step towards removing the horror that is
TargetAsmInfo.

llvm-svn: 135237
 2011-07-15 02:09:41 +00:00
Bill Wendling 9b8605f787 Remove setting the bit for personality function. It should be set by the linker. 
llvm-svn: 135236
 2011-07-15 01:42:32 +00:00
Bill Wendling c998f71d14 Encode that we have a personality function. 
llvm-svn: 135227
 2011-07-15 00:07:31 +00:00
Bill Wendling dafd598f05 * If we have an LSDA, we need to mark it in the encoding. 
* The personality function should be encoded as an absolute pointer to the function.

llvm-svn: 135215
 2011-07-14 23:34:45 +00:00
Evan Cheng c7ac690ba2 Unfortunately several files in MC are badly violating layering rule by using 
TargetAsmInfo, which in turn pulls in TargetRegisterInfo, etc. :-( There are
other cases of violations, but this is probably the worst.

This patch is but one small step towards fixing this. 500 more steps to go. :-(

llvm-svn: 135131
 2011-07-14 05:43:07 +00:00
Bill Wendling ee6e776be2 Don't emit the FDE end label if the last thing emitted was a compact unwind and 
not the FDE

llvm-svn: 135020
 2011-07-13 00:49:09 +00:00
Bill Wendling b6adf46f62 Add a target hook to encode the compact unwind information. 
llvm-svn: 134577
 2011-07-07 00:54:13 +00:00
Bill Wendling 7ed5625082 Clean up the #includes. 
llvm-svn: 134557
 2011-07-06 22:52:32 +00:00
Bill Wendling c737ac1816 Remove tabs. 
llvm-svn: 134212
 2011-06-30 23:59:38 +00:00
Bill Wendling 40cc749788 Improve comment: Show the register the DWARF label is added to. 
llvm-svn: 134209
 2011-06-30 23:47:40 +00:00
Bill Wendling 2fd8d775df Add one more comment to the FDE verbose asm output. 
llvm-svn: 134200
 2011-06-30 22:35:49 +00:00
Bill Wendling f166ab447e Add comments to the FDE. 
llvm-svn: 134196
 2011-06-30 22:02:20 +00:00
Bill Wendling e7fe47e53b Add more comments to the ASM output for the CIE's "moves". 
llvm-svn: 134194
 2011-06-30 21:45:12 +00:00
Bill Wendling 567a1aee85 Add comments to the ASM output to help understand the compact unwind and CIE tables. 
llvm-svn: 134191
 2011-06-30 21:25:51 +00:00
Bill Wendling 7517466970 * Use the proper size to output the range size. 
* Rough in the compact encoding part.

llvm-svn: 134119
 2011-06-30 00:30:52 +00:00
Bill Wendling 4cdb206e76 Stupid error: If the LSDA and Personality functions aren't there, emit 0 instead 
of the encoding.

llvm-svn: 134117
 2011-06-29 23:53:16 +00:00
Bill Wendling 8fa4ada5cf We don't want to use relocations inside the compact unwind section. Just use the 
symbols instead.

llvm-svn: 134115
 2011-06-29 23:49:12 +00:00
Bill Wendling 25fbb92320 Use a reference. Don't make a useless copy of the vector. 
llvm-svn: 133707
 2011-06-23 07:55:41 +00:00
Bill Wendling a4b9d1f97b Formatting changes. No functionality change. 
llvm-svn: 133706
 2011-06-23 07:44:54 +00:00
Bill Wendling 9af2fa9d1b Use the presence of the __compact_unwind section to indicate that a target 
supports compact unwind info instead of having a separate flag indicating this.

llvm-svn: 133685
 2011-06-23 05:13:28 +00:00
Bill Wendling e8fc92ad46 Some skeleton code to emit the compact unwind. If the information is unable to 
be emitted in a compact way, we then default to emitting a CIE and FDE.

llvm-svn: 133676
 2011-06-23 01:06:23 +00:00
Benjamin Kramer f7cb7ef996 Directly print to a raw_ostream instead of printing to a buffer first. 
llvm-svn: 133352
 2011-06-18 14:42:47 +00:00
Jim Grosbach 8aded86edb No reason not to allow defining the CFA as a reg w/ offset zero. 
llvm-svn: 131760
 2011-05-20 21:50:09 +00:00
Rafael Espindola de32fa163f Avoid a gcc warning. 
llvm-svn: 131161
 2011-05-10 22:28:35 +00:00
Rafael Espindola 99f6735532 On MachO, unlike ELF, there should be no relocation to produce the CIE pointer. 
llvm-svn: 131149
 2011-05-10 20:59:42 +00:00
Rafael Espindola d0d2354258 The EH symbols are only needed in eh_frame, not debug_frame. 
llvm-svn: 131146
 2011-05-10 19:51:53 +00:00
Rafael Espindola 27390b4a0e In a debug_frame the cfi offset is to the start of the debug_frame section! 
llvm-svn: 131129
 2011-05-10 15:20:23 +00:00
Rafael Espindola 1ecb12fc57 Add support for producing .deubg_frame sections. 
llvm-svn: 131121
 2011-05-10 03:54:12 +00:00
Rafael Espindola b6444c0401 Small cleanups. 
llvm-svn: 131120
 2011-05-10 03:26:21 +00:00
Rafael Espindola 0e130d1d37 Remove unused argument. 
llvm-svn: 131118
 2011-05-10 03:01:39 +00:00
NAKAMURA Takumi 392445823d Eliminate an unused line to fix a warning. 
llvm-svn: 131078
 2011-05-08 23:19:04 +00:00
Rafael Espindola ab39c63538 Don't force relaxation of AdvanceLoc instructions on OS X. gdb is happy with 
the smaller encoding and this cuts 270336 bytes from a release version of
clang and 1246272 bytes from a debug build.

llvm-svn: 131067
 2011-05-08 14:35:21 +00:00
Rafael Espindola bcabcdcedd Switch Darwin to the generic CIE/FDE printer. 
llvm-svn: 131031
 2011-05-06 22:29:04 +00:00
Daniel Dunbar f6daf94ab2 MCDwarf: Don't save Twine to local variable, this is almost never safe to do 
(and should thus never be done).
 - Should fix a crash on win32.

llvm-svn: 130793
 2011-05-03 21:33:37 +00:00
Rafael Espindola 750cb61553 GCC uses a different encoding of pointers in the FDE when using 
-fno-dwarf2-cfi-asm. Implement the same behavior.

llvm-svn: 130637
 2011-05-01 04:49:54 +00:00
Rafael Espindola fd05785324 Simplify the handling of pcrel relocations on ELF. Now we do the right thing 
for all symbol differences and can drop the old EmitPCRelSymbolValue
method.

This also make getExprForFDESymbol on ELF equal to the one on MachO, and it
can be made non-virtual.

llvm-svn: 130634
 2011-05-01 03:50:49 +00:00
Rafael Espindola 6a85f9b42e Avoid some uses of .uleb128. This is a small speedup and more importantly 
lets this code be used when producing assembly code for old assemblers without
uleb support.

llvm-svn: 130544
 2011-04-29 21:50:57 +00:00
Rafael Espindola 68067664c3 Last bit by bit compatibility patch to MCDwarf.cpp: If a FDE with no LSDA is 
assigned to a CIE that requires one, just output a 0.

llvm-svn: 130472
 2011-04-29 03:06:29 +00:00
Rafael Espindola 7c7151512c Add an alternative implementation of CIE and FDE emission that outputs them 
in the same order as the one in CodeGen.

llvm-svn: 130471
 2011-04-29 02:42:28 +00:00
Rafael Espindola 6bd6a70837 Add the getExprForFDESymbol method that responsible for computing the 
expressions used in the FDE to refer to symbols.

llvm-svn: 130437
 2011-04-28 21:04:39 +00:00
Rafael Espindola c5dac4df2e Add a getExprForPersonalitySymbol method to MCAsmInfo. Use it when 
converting the symbol passed to .cfi_personality into bytes is the file.

llvm-svn: 130400
 2011-04-28 16:09:09 +00:00
Rafael Espindola 349c3298da Mark the EH symbol global or weak if the corresponding function is. 
llvm-svn: 130397
 2011-04-28 12:50:37 +00:00
Rafael Espindola 2eeee8cfef Add a small temporary hack for producing identical eh_frame sections on OS X. 
This removes one of the main advantages of moving eh_frame to MC, but
makes the transition a lot easier to debug (run md5).

llvm-svn: 130379
 2011-04-28 04:04:14 +00:00
Rafael Espindola bf60fb0a37 Produce the EH_frame# symbols if needed. 
llvm-svn: 130378
 2011-04-28 03:26:11 +00:00
Rafael Espindola 96b07932a3 Forward isFunctionEHFrameSymbolPrivate. If it is false, produce the foo.eh 
symbols.

llvm-svn: 130375
 2011-04-28 02:46:42 +00:00
Rafael Espindola ae124da625 Force some values to be absolute and align based on the FDE pointers size. A small 
step towards using .cfi_* on OS X.

llvm-svn: 130273
 2011-04-27 01:43:49 +00:00
Chandler Carruth bab81b9797 Delete the other unused variable in this function. Sorry I missed this 
the first time through.

llvm-svn: 129969
 2011-04-22 01:29:18 +00:00
Chandler Carruth ea41470726 Remove an unused variable from a function. This is a likely cut-paste-o. 
Silences GCC warning.

I wonder why Clang doesn't warn on this...

llvm-svn: 129968
 2011-04-22 01:21:06 +00:00
Rafael Espindola 5395f44fe8 Compute the size of the FDE encoding instead of hard coding it. Update 
X8664_ELFTargetObjectFile::getFDEEncoding to match reality.

llvm-svn: 129959
 2011-04-22 00:08:43 +00:00
Rafael Espindola 6aea59268a Remove unused argument. 
llvm-svn: 129955
 2011-04-21 23:39:26 +00:00
Rafael Espindola ea61f22dd3 Don't pass address spaces to EmitULEB128IntValue. 
llvm-svn: 129953
 2011-04-21 23:26:40 +00:00
Rafael Espindola fd794affe5 Remove LastOffset from the asm parser. 
llvm-svn: 129378
 2011-04-12 18:53:30 +00:00
Rafael Espindola 1ec0f46169 Fix the case of a .cfi_rel_offset before any .cfi_def_cfa_offset. 
llvm-svn: 129362
 2011-04-12 16:12:03 +00:00
Rafael Espindola 2e1c9d2188 Implement .cfi_same_value. 
llvm-svn: 129361
 2011-04-12 15:31:05 +00:00
Anton Korobeynikov 2f93128109 Rename TargetFrameInfo into TargetFrameLowering. Also, put couple of FIXMEs and fixes here and there. 
llvm-svn: 123170
 2011-01-10 12:39:04 +00:00
Benjamin Kramer 570dd787a6 Make a bunch of symbols internal. 
llvm-svn: 122642
 2010-12-30 22:34:44 +00:00
Rafael Espindola 46a5b05207 Correctly encode pcrel|indirect. 
llvm-svn: 122624
 2010-12-29 04:31:26 +00:00
Rafael Espindola 563301dfdb Fix bug when trying to output uint16_t or uint32_t. 
llvm-svn: 122615
 2010-12-29 02:30:49 +00:00
Rafael Espindola 290d71671e Implement cfi_def_cfa. Also don't convert to dwarf reg numbers twice. Looks 
like 6 is a fixed point of that and so the previous tests were OK :-)

llvm-svn: 122614
 2010-12-29 01:42:56 +00:00
Rafael Espindola 6bbfb6c06c Don't produce a "DW_CFA_advance_loc 0". 
llvm-svn: 122609
 2010-12-28 23:38:03 +00:00
Rafael Espindola 85d91982ca Implement .cfi_remember_state and .cfi_restore_state. 
llvm-svn: 122602
 2010-12-28 18:36:23 +00:00
Duncan Sands 3784c5ea3c Fix warning about size potentially being used uninitialized 
when doing a release build.

llvm-svn: 122594
 2010-12-28 10:02:42 +00:00
Rafael Espindola 736a35d9ab Relax address updates in the eh_frame section. 
llvm-svn: 122591
 2010-12-28 05:39:27 +00:00
Rafael Espindola a75b87b55a Start adding basic support for emitting the call frame instructions. 
llvm-svn: 122590
 2010-12-28 04:15:37 +00:00
Rafael Espindola 1de2dd0e5e Add support for .cfi_lsda. 
llvm-svn: 122584
 2010-12-27 15:56:22 +00:00
Rafael Espindola 2ac8355ecd Add support for the same encodings of the personality function that gnu as 
supports.

llvm-svn: 122577
 2010-12-27 00:36:05 +00:00
Rafael Espindola 54462cd730 Fix .cfi_personality on 32 bit systems. 
llvm-svn: 122570
 2010-12-26 22:47:37 +00:00
Rafael Espindola 9141b611ad Add basic support for .cfi_personality. 
llvm-svn: 122566
 2010-12-26 20:20:31 +00:00
Rafael Espindola 32c74ea3ab "Fix" FDE alignment to match what gas does. 
llvm-svn: 122006
 2010-12-17 00:28:02 +00:00
Rafael Espindola 0a017a6db2 Fixed version of 121434 with no new memory leaks. 
llvm-svn: 121471
 2010-12-10 07:39:47 +00:00
Rafael Espindola a945a34c73 Revert my previous patch to make the valgrind bots happy. 
llvm-svn: 121461
 2010-12-10 04:01:09 +00:00
Rafael Espindola 56eb741237 Initial support for the cfi directives. This is just enough to get 
f:
        .cfi_startproc
        nop
        .cfi_endproc

assembled (on ELF).

llvm-svn: 121434
 2010-12-09 23:48:29 +00:00
Rafael Espindola d66e65df03 Use const references. 
llvm-svn: 121426
 2010-12-09 23:08:35 +00:00
Rafael Espindola 44bbe36de6 Second try at making direct object emission produce the same results 
as llc + llvm-mc. This time ELF is not changed and I tested that llvm-gcc
bootstrap on darwin10 using darwin9's assembler and linker.

llvm-svn: 121006
 2010-12-06 17:27:56 +00:00
Rafael Espindola dee3062373 Revert previous two patches while I try to find out how to make both 
linux and darwin assemblers happy :-(

llvm-svn: 121004
 2010-12-06 15:35:15 +00:00
Rafael Espindola 34a06a0802 Add an EmitAbsValue helper method and use it in cases where we want to be sure 
that no relocations are used (on MochO).
Fixes llc producing different output from llc + llvm-mc.

llvm-svn: 121000
 2010-12-06 14:53:14 +00:00
Rafael Espindola 99e026dbca Remember the contents of leb and dwarfline fragments when relaxing. This avoids 
having to evaluate the expression again when writing.

llvm-svn: 120920
 2010-12-04 21:58:52 +00:00
Rafael Espindola 1c8ac8f027 There are two reasons why we might want to use 
foo = a - b
.long foo
instead of just
.long a - b

First, on darwin9 64 bits the assembler produces the wrong result. Second,
if "a" is the end of the section all darwin assemblers (9, 10 and mc) will not
consider a - b to be a constant but will if the dummy foo is created.

Split how we handle these cases. The first one is something MC should take care
of. The second one has to be handled by the caller.

llvm-svn: 120889
 2010-12-04 03:21:47 +00:00
Rafael Espindola 1048e75fb9 Next step: Only pad debug_line when the target is darwin. Add a FIXME to avoid 
doing that if the target is darwin10 or newer.

This fixes
*) Direct object emission was producing objects without the workaround on
   darwin9.
*) Assembly printing was producing objects with the workaround on linux.

llvm-svn: 120866
 2010-12-04 00:31:13 +00:00
Rafael Espindola f8af778e1f First step in fixing MC. Make it clear that we are avoiding a bug in the 
darwin9 linker, what is needed to avoid it and where to get more information.

Also make the workaround simpler. Just the regular end_sequence we normally
create is more than 4 bytes.

Tested by building cctools and ld64 from darwin9 on a darwin10 system and using
those. I checked that I was able to reproduce the bootstrap failure when
the the workaround was disabled.

llvm-svn: 120854
 2010-12-03 23:36:59 +00:00
Rafael Espindola 57ab708bdd Try to resolve symbol differences early, and if successful create a plain 
data fragment. This reduces the time to assemble the test in 8711 from 60s to
54s.

llvm-svn: 120767
 2010-12-03 00:55:40 +00:00
Devang Patel 5eed2e63f8 It may not be an option to skip .debug_line if there are file reference in already emitted debug info. So, for now, emit dummy line table entry to make older linker and assemblers happy. This is not a new behavior, original AsmPrinter emitted similar line table entries. 
llvm-svn: 120760
 2010-12-03 00:10:48 +00:00
Devang Patel 8cabd938ed Use set directive for StartMinusEndExpr. 
This is a fix for llvm-gcc-i386-darwin9 buildbot failure.

llvm-svn: 120742
 2010-12-02 21:32:30 +00:00
Rafael Espindola 556f203d64 Remove some #includes. 
llvm-svn: 119967
 2010-11-22 11:53:17 +00:00
Rafael Espindola 9900b4802e Add a MCLineSectionOrder vector so that we produce the line tables in a 
deterministic order.

llvm-svn: 119795
 2010-11-19 07:41:23 +00:00
Rafael Espindola b58867ccba Change some methods in MCDwarf.cpp to be able to handle an arbitrary 
MCStreamer instead of just MCObjectStreamer. Address changes cannot
be as efficient as we have to use DW_LNE_set_addres, but at least
most of the logic is shared.

This will be used so that, with CodeGen still using EmitDwarfLocDirective,
llvm-gcc is able to produce debug_line sections without needing an
assembler that supports .loc.

llvm-svn: 119777
 2010-11-19 02:26:16 +00:00
Rafael Espindola 1d37f35eea Fix the encoding of negative line deltas. 
llvm-svn: 118962
 2010-11-13 01:06:27 +00:00
Rafael Espindola c4f4b2e878 Remove what looks like dead code in the production of debug lines. 
We only produce debug line information if we have seen a line directive, so
this code is dead. Also, if we want to be bug by bug compatible with
gas and sometimes produce "empty" .debug_line sections, this will
match the content produced by gas.

llvm-svn: 118914
 2010-11-12 18:41:26 +00:00
Rafael Espindola 5e874982f2 Add support for expressions in .sleb/.uleb directives. 
llvm-svn: 118023
 2010-11-02 17:22:24 +00:00
Kevin Enderby a68d004d88 Incorporate suggestions by Daniel Dunbar after his review. Thanks Daniel! 
1) Changed ValidateDwarfFileNumber() to isValidDwarfFileNumber() to be better
   named.  Since it is just a predicate and isn't actually changing any state.

2) Added a missing return in the comments for setCurrentDwarfLoc() in 
   include/llvm/MC/MCContext.h for fix formatting.

3) Changed clearDwarfLocSeen() to ClearDwarfLocSeen() since it does change
   state.

4) Simplified the last test in isValidDwarfFileNumber() to just a one line
   boolean test of MCDwarfFiles[FileNumber] != 0 for the final return statement.

llvm-svn: 115551
 2010-10-04 20:17:24 +00:00
Kevin Enderby e46564a4a8 This is the last major patch to implement support for the .loc directive 
and output the dwarf line number tables.  This contains the code to emit and
encode the dwarf line tables from the previously gathered information in the
MCLineSection objects.  This contains all the details to encode the line and
address deltas into the dwarf line table.

To do this an MCDwarfLineAddrFragment has been added.

Also this moves the interface code out of Mach-O streamer into
MCDwarf so it should be useable by other object file formats.

There is now one call to be made from an MCObjectStreamer
EmitInstruction() method:
   MCLineEntry::Make(this, getCurrentSection());
to create a line entry after each instruction is assembled.

And one call call to be made from an MCObjectStreamer Finish() method:
   MCDwarfFileTable::Emit(this, DwarfLineSection);
when getContext().hasDwarfFiles() is true and is passed a object file specific
MCSection where to emit the dwarf file and the line tables.

This appears to now be correct for 32-bit targets, at least x86.  But the
relocation entries for 64-bit Darwin needs some further work which is next
up to work on.  So for now the 64-bit Mach-O target does not output the
dwarf file and line tables.

llvm-svn: 115157
 2010-09-30 16:52:03 +00:00
Kevin Enderby e5930f142a Added first bit of support for the dwarf .file directive. This patch collects 
the info from the .file directive and makes file and directory tables that
will eventually be put out as part of the dwarf info in the output file.

llvm-svn: 109651
 2010-07-28 20:55:35 +00:00