Commit Graph

20 Commits

Author SHA1 Message Date
Reed Kotler 0c1745e56a EmitDebugLabel should by default be the same as EmitLabel everywhere.
It must be explicity set in MCPureStreamer because otherwise it will
inherit incorrectly from the parent.

llvm-svn: 170383
2012-12-17 23:41:45 +00:00
NAKAMURA Takumi c7146e251d MCPureStreamer.cpp: Try to fix build, pruning EmitDebugLabel().
llvm-svn: 170280
2012-12-16 04:23:20 +00:00
Reed Kotler aee4d5d194 This patch is needed to make c++ exceptions work for mips16.
Mips16 is really a processor decoding mode (ala thumb 1) and in the same
program, mips16 and mips32 functions can exist and can call each other.

If a jal type instruction encounters an address with the lower bit set, then
the processor switches to mips16 mode (if it is not already in it). If the
lower bit is not set, then it switches to mips32 mode.

The linker knows which functions are mips16 and which are mips32.
When relocation is performed on code labels, this lower order bit is
set if the code label is a mips16 code label.

In general this works just fine, however when creating exception handling
tables and dwarf, there are cases where you don't want this lower order
bit added in.

This has been traditionally distinguished in gas assembly source by using a
different syntax for the label.

lab1:      ; this will cause the lower order bit to be added
lab2=.     ; this will not cause the lower order bit to be added

In some cases, it does not matter because in dwarf and debug tables
the difference of two labels is used and in that case the lower order
bits subtract each other out.

To fix this, I have added to mcstreamer the notion of a debuglabel.
The default is for label and debug label to be the same. So calling
EmitLabel and EmitDebugLabel produce the same result.

For various reasons, there is only one set of labels that needs to be
modified for the mips exceptions to work. These are the "$eh_func_beginXXX" 
labels.

Mips overrides the debug label suffix from ":" to "=." .

This initial patch fixes exceptions. More changes most likely
will be needed to DwarfCFException to make all of this work
for actual debugging. These changes will be to emit debug labels in some
places where a simple label is emitted now.

Some historical discussion on this from gcc can be found at:
http://gcc.gnu.org/ml/gcc-patches/2008-08/msg00623.html
http://gcc.gnu.org/ml/gcc-patches/2008-11/msg01273.html 

llvm-svn: 170279
2012-12-16 04:00:45 +00:00
Eli Bendersky a31a894eed Refactor MCInstFragment and MCDataFragment to adhere to a common interface,
which removes code duplication and prepares the ground for future additions.

Full discussion:
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20121203/158233.html

llvm-svn: 169626
2012-12-07 19:13:57 +00:00
Eli Bendersky ea2824dc88 Lift EmitAssignment into MCObjectStreamer which gets rid of at least three
duplicate implementations in format-specific streamers.

llvm-svn: 169613
2012-12-07 17:42:41 +00:00
Evan Cheng f5bd6c6510 EmitZerofill should take a 64-bit size or else it's chopping off large zero-filled global. rdar://11729134
llvm-svn: 159023
2012-06-22 20:14:46 +00:00
Jim Grosbach b591277c4a Better diagnostic for malformed .org assembly directive.
Provide source line number information.

llvm-svn: 149101
2012-01-27 00:37:08 +00:00
David Blaikie 46a9f016c5 More dead code removal (using -Wunreachable-code)
llvm-svn: 148578
2012-01-20 21:51:11 +00:00
Rafael Espindola 0708209642 Split Finish into Finish and FinishImpl to have a common place to do end of
file error checking. Use that to error on an unfinished cfi_startproc.

The error is not nice, but is already better than a segmentation fault.

llvm-svn: 147717
2012-01-07 03:13:18 +00:00
Nick Lewycky 40f8f2ff24 Add support for a new extension to the .file directive:
.file filenumber "directory" "filename"

This removes one join+split of the directory+filename in MC internals. Because
bitcode files have independent fields for directory and filenames in debug info,
this patch may change the .o files written by existing .bc files.

llvm-svn: 142300
2011-10-17 23:05:28 +00:00
Benjamin Kramer 6397051ece Don't drop alignment info on local common symbols.
- On COFF the .lcomm directive has an alignment argument.
- On ELF we fall back to .local + .comm

Based on a patch by NAKAMURA Takumi.

Fixes PR9337, PR9483 and PR10128.

llvm-svn: 138976
2011-09-01 23:04:27 +00:00
Evan Cheng 5928e69d20 Rename TargetAsmBackend to MCAsmBackend; rename createAsmBackend to createMCAsmBackend.
llvm-svn: 136010
2011-07-25 23:24:55 +00:00
Cameron Zwarich fcf51fd298 Roll out r126425 and r126450 to see if it fixes the failures on the buildbots.
llvm-svn: 126488
2011-02-25 16:30:32 +00:00
Devang Patel b037383a35 Enable DebugInfo support for COFF object files.
Patch by Nathan Jeffords!

llvm-svn: 126425
2011-02-24 21:04:00 +00:00
Rafael Espindola 58ac6e1677 Add support for pushsection and popsection. Patch by Joerg Sonnenberger.
llvm-svn: 125629
2011-02-16 01:08:29 +00:00
Rafael Espindola 93e3cf0ebd Sorry for such a large commit. The summary is that only MachO cares about the
actuall addresses in a .o file, so it is better to let the MachO writer compute
it.

This is good for two reasons. First, areas that shouldn't care about
addresses now don't have access to it. Second, the layout of each section
is independent. I should use this in a subsequent commit to speed it up.

Most of the patch is just removing the section address computation. The two
interesting parts are the change on how we handle padding in the end
of sections and how MachO can get the address of a-b when a and b are in
different sections.

Since now the expression evaluation normally doesn't know the section address,
it will think that a-b needs relocation and let the MachO writer know. Once
it has computed the section addresses, it calls back the expression evaluation
with the section addresses to resolve these expressions.

The remaining problem is the handling of padding. Currently it will create
a special alignment fragment at the end. Since that fragment doesn't update
the alignment of the section, it needs the real address to be computed.

Since now the layout will not compute a-b with a and b in different sections,
the only effect that the special alignment fragment has is update the
address size of the section. This can also be done by the MachO writer.

llvm-svn: 121076
2010-12-07 00:27:36 +00:00
Rafael Espindola 0710e3771f Forgot the MCPureStreamer::EmitValue in the previous commit.
llvm-svn: 120270
2010-11-28 23:13:47 +00:00
Rafael Espindola b746531c2c Avoid code duplication in the many unsupported EmitGPRel32Value implementations.
llvm-svn: 120243
2010-11-28 15:09:24 +00:00
Rafael Espindola 8a3a7923eb Define generic 1, 2 and 4 byte pc relative relocations. They are common
and at least the 4 byte one will be needed to implement the .cfi_* directives.

llvm-svn: 120240
2010-11-28 14:17:56 +00:00
Daniel Dunbar 95d37be1a9 MC-JIT: Stub out "pure" streamer.
- No immediate use, but maybe someone feels like hacking on it.

llvm-svn: 119510
2010-11-17 16:06:47 +00:00