llvm-project/llvm
Bill Schmidt 8893a3d159 [PowerPC] Preparatory refactoring for making prologue and epilogue
safe on PPC32 SVR4 ABI

[Patch and following text by Mark Minich; committing on his behalf.]

There are FIXME's in PowerPC/PPCFrameLowering.cpp, method
PPCFrameLowering::emitPrologue() related to "negative offsets of R1"
on PPC32 SVR4. They're true, but the real issue is that on PPC32 SVR4
(and any ABI without a Red Zone), no spills may be made until after
the stackframe is claimed, which also includes the LR spill which is
at a positive offset. The same problem exists in emitEpilogue(),
though there's no FIXME for it. I intend to fix this issue, making
LLVM-compiled code finally safe for use on SVR4/EABI/e500 32-bit
platforms (including in particular, OS-free embedded systems & kernel
code, where interrupts may share the same stack as user code).

In preparation for making these changes, to make the diffs for the
functional changes less cluttered, I am providing the non-functional
refactorings in two stages:

Stage 1 does some minor fluffy refactorings to pull multiple method
calls up into a single bool, creating named bools for repeated uses of
obscure logic, moving some code up earlier because either stage 2 or
my final version will require it earlier, and rewording/adding some
comments. My stage 1 changes can be characterized as primarily fluffy
cleanup, the purpose of which may be unclear until the stage 2 or
final changes are made.

My stage 2 refactorings combine the separate PPC32 & PPC64 logic,
which is currently performed by largely duplicate code, into a single
flow, with the differences handled by a group of constants initialized
early in the methods.

This submission is for my stage 1 changes. There should be no
functional changes whatsoever; this is a pure refactoring.

llvm-svn: 188573
2013-08-16 20:05:04 +00:00
..
autoconf Remove all checking for the various terminfo headers (term.h and 2013-08-12 10:40:11 +00:00
bindings We're in 3.4 land now. 2013-05-07 20:31:28 +00:00
cmake Re-disabling C4291 warnings for MSVC because AttributeList.h requires it. This was accidentally removed in r187279. 2013-08-16 03:06:38 +00:00
docs Sphinx refuses to render this code block. Try adding a newline. 2013-08-14 16:18:47 +00:00
examples ExceptionDemo.cpp: Tweak a @param. [-Wdocumentation] 2013-07-29 11:03:50 +00:00
include Removing unused functionality. 2013-08-16 17:33:57 +00:00
lib [PowerPC] Preparatory refactoring for making prologue and epilogue 2013-08-16 20:05:04 +00:00
projects Build with the $RDYNAMIC flag on Darwin as well as other platforms. 2013-08-04 22:06:11 +00:00
runtime Use @rpath for libraries rather than @executable_path on OSX. 2013-08-02 01:51:52 +00:00
test [tests] Another attempt to workaround broken misched-copy.s test on some buildbots. 2013-08-16 18:01:18 +00:00
tools llvm-symbolizer: add support for .gnu_debuglink section 2013-08-14 17:09:30 +00:00
unittests Removing a spurious semi-colon; this macro expands into a namespace. 2013-08-16 01:53:58 +00:00
utils FileCheck: Fix stray quote in CHECK-LABEL error message. 2013-08-16 17:29:01 +00:00
.arcconfig
.gitignore
CMakeLists.txt CMake: polish the Windows packaging rules 2013-08-15 23:44:31 +00:00
CODE_OWNERS.TXT Add more owners to CODE_OWNERS.TXT (Kostya Serebryany: AddressSanitizer and ThreadSanitizer; Evgeniy Stepanov: MemorySanitizer) 2013-06-27 08:47:12 +00:00
CREDITS.TXT Test commit. 2013-08-16 18:09:06 +00:00
LICENSE.TXT Be more specific and capitalize filenames. 2013-05-21 21:22:34 +00:00
LLVMBuild.txt
Makefile Fix regular expression used by 'make update' to only look for 'I' and '?' at the start of svn info results and to check for spaces after 'I' instead of just after '?'. 2013-07-03 14:48:37 +00:00
Makefile.common
Makefile.config.in Add an autoconf option for turning on -gsplit-dwarf by default 2013-06-25 01:12:25 +00:00
Makefile.rules Remove oddly named libraries with "make uninstall-local" 2013-08-06 12:50:45 +00:00
README.txt test 2013-04-17 05:34:03 +00:00
configure Remove all checking for the various terminfo headers (term.h and 2013-08-12 10:40:11 +00:00
llvm.spec.in

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