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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>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).<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>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:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>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.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>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.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>This submission is for my stage 1 changes. There should be no functional changes whatsoever; this is a pure refactoring.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><a href="http://llvm-reviews.chandlerc.com/D1343">http://llvm-reviews.chandlerc.com/D1343</a><o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>