summaryrefslogtreecommitdiffstats
path: root/llvm/test/CodeGen/X86/shrink-wrap-chkstk.ll
Commit message (Collapse)AuthorAgeFilesLines
* Re-commit r269828 "X86: Avoid using _chkstk when lowering WIN_ALLOCA ↵Hans Wennborg2016-05-181-2/+2
| | | | | | | | | | | | instructions" with an additional fix to make RegAllocFast ignore undef physreg uses. It would previously get confused about the "push %eax" instruction's use of eax. That method for adjusting the stack pointer is used in X86FrameLowering::emitSPUpdate as well, but since that runs after register-allocation, we didn't run into the RegAllocFast issue before. llvm-svn: 269949
* Revert r269828 "X86: Avoid using _chkstk when lowering WIN_ALLOCA instructions"Hans Wennborg2016-05-171-2/+2
| | | | | | Seems to have broken the Windows ASan bot. Reverting while investigating. llvm-svn: 269833
* X86: Avoid using _chkstk when lowering WIN_ALLOCA instructionsHans Wennborg2016-05-171-2/+2
| | | | | | | | | | | | | | | This patch moves the expansion of WIN_ALLOCA pseudo-instructions into a separate pass that walks the CFG and lowers the instructions based on a conservative estimate of the offset between the stack pointer and the lowest accessed stack address. The goal is to reduce binary size and run-time costs by removing calls to _chkstk. While it doesn't fix all the code quality problems with inalloca calls, it's an incremental improvement for PR27076. Differential Revision: http://reviews.llvm.org/D20263 llvm-svn: 269828
* [X86] Enable call frame optimization ("mov to push") not only for optsize ↵Hans Wennborg2016-03-301-2/+2
| | | | | | | | | | (PR26325) The size savings are significant, and from what I can tell, both ICC and GCC do this. Differential Revision: http://reviews.llvm.org/D18573 llvm-svn: 264966
* Revert "[X86] Elide references to _chkstk for dynamic allocas"Reid Kleckner2016-03-021-1/+1
| | | | | | | | | | | | | | | This reverts commit r262370. It turns out there is code out there that does sequences of allocas greater than 4K: http://crbug.com/591404 The goal of this change was to improve the code size of inalloca call sequences, but we got tangled up in the mess of dynamic allocas. Instead, we should come back later with a separate MI pass that uses dominance to optimize the full sequence. This should also be able to remove the often unneeded stacksave/stackrestore pairs around the call. llvm-svn: 262505
* [X86] Elide references to _chkstk for dynamic allocasDavid Majnemer2016-03-011-1/+1
| | | | | | | | | | | | | | | The _chkstk function is called by the compiler to probe the stack in an order consistent with Windows' expectations. However, it is possible to elide the call to _chkstk and manually adjust the stack pointer if we can prove that the allocation is fixed size and smaller than the probe size. This shrinks chrome.dll, chrome_child.dll and chrome.exe by a cummulative ~133 KB. Differential Revision: http://reviews.llvm.org/D17679 llvm-svn: 262370
* [X86] Fix a shrink-wrapping miscompile around __chkstkReid Kleckner2016-02-171-0/+35
| | | | | | | | | __chkstk clobbers EAX. If EAX is live across the prologue, then we have to take extra steps to save it. We already had code to do this if EAX was a register parameter. This change adapts it to work when shrink wrapping is used. llvm-svn: 261039
* [X86] Put no-op ADJCALLSTACK markers around all dynamic loweringsReid Kleckner2015-12-031-0/+37
Summary: These ADJCALLSTACK markers don't generate code, but they keep dynamic alloca code that calls chkstk out of the prologue. This slightly pessimizes inalloca calls by preventing some register copy coalescing, but I can live with that. Reviewers: qcolombet Subscribers: hans, llvm-commits Differential Revision: http://reviews.llvm.org/D15200 llvm-svn: 254645
OpenPOWER on IntegriCloud