Commit Graph

10 Commits

Author SHA1 Message Date
Hal Finkel
db31bd31d6 LocalStackSlotAllocation improvements
First, taking advantage of the fact that the virtual base registers are allocated in order of the local frame offsets, remove the quadratic register-searching behavior. Because of the ordering, we only need to check the last virtual base register created.

Second, store the frame index in the FrameRef structure, and get the frame index and the local offset from this structure at the top of the loop iteration. This allows us to de-nest the loops in insertFrameReferenceRegisters (and I think makes the code cleaner). I also moved the needsFrameBaseReg check into the first loop over instructions so that we don't bother pushing FrameRefs for instructions that don't want a virtual base register anyway.

Lastly, and this is the only functionality change, avoid the creation of single-use virtual base registers. These are currently not useful because, in general, they end up replacing what would be one r+r instruction with an add and a r+i instruction. Committing this removes the XFAIL in CodeGen/PowerPC/2007-09-07-LoadStoreIdxForms.ll

Jim has okayed this off-list.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180799 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-30 20:04:37 +00:00
Evan Cheng
afad0fe59a Fix more places which should be checking for iOS, not darwin.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147513 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-04 01:55:04 +00:00
Jim Grosbach
3e333637f1 Thumb1 had two patterns for the same load-from-constant-pool instruction.
Canonicalize on tLDRpci and remove tLDRcp.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121920 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-15 23:52:36 +00:00
Evan Cheng
ab5c703fdb Fix epilogue codegen to avoid leaving the stack pointer in an invalid
state. Previously Thumb2 would restore sp from fp like this:
mov sp, r7
sub, sp, #4
If an interrupt is taken after the 'mov' but before the 'sub', callee-saved
registers might be clobbered by the interrupt handler. Instead, try
restoring directly from sp:
add sp, #4
Or, if necessary (with VLA, etc.) use a scratch register to compute sp and
then restore it:
sub.w r4, r7, #8
mov sp, r7
rdar://8465407


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119977 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-22 18:12:04 +00:00
Jim Grosbach
ae47c6d69e Enable pre-RA virtual frame base register allocation. rdar://8277890
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112127 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-26 00:58:06 +00:00
Evan Cheng
ac096808a3 Re-apply r110655 with fixes. Epilogue must restore sp from fp if the function stack frame has a var-sized object.
Also added a test case to check for the added benefit of this patch: it's optimizing away the unnecessary restore of sp from fp for some non-leaf functions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110707 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-10 19:30:19 +00:00
Daniel Dunbar
4bd828f781 Revert r110655, "Fix ARM hasFP() semantics. It should return true whenever FP
register is", it breaks a couple test-suite tests.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110701 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-10 18:32:02 +00:00
Evan Cheng
c9aed19747 Fix ARM hasFP() semantics. It should return true whenever FP register is
reserved, not available for general allocation. This eliminates all the
extra checks for Darwin.

This change also fixes the use of FP to access frame indices in leaf
functions and cleaned up some confusing code in epilogue emission.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110655 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-10 06:26:49 +00:00
Dan Gohman
fce288fc91 Eliminate more uses of llvm-as and llvm-dis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81293 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-09 00:09:15 +00:00
Evan Cheng
9f76ed5127 Move thumb and thumb2 tests into separate directories.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74068 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-24 06:36:07 +00:00