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path: root/lib/CodeGen/SimpleRegisterCoalescing.cpp
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2010-07-09Deal with a few remaining spots that assume physical registers have live ↵Jakob Stoklund Olesen
intervals. This fixes PR7601. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107955 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-09Fix broken isCopy handling in TrimLiveIntervalToLastUse.Jakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107950 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-08Revert "Fix broken isCopy handling in TrimLiveIntervalToLastUse"Jakob Stoklund Olesen
This reverts commit 107921. It broke the clang self host. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107926 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-08Fix broken isCopy handling in TrimLiveIntervalToLastUseJakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107921 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-08Convert EXTRACT_SUBREG to COPY when emitting machine instrs.Jakob Stoklund Olesen
EXTRACT_SUBREG no longer appears as a machine instruction. Use COPY instead. Add isCopy() checks in many places using isMoveInstr() and isExtractSubreg(). The isMoveInstr hook will be removed later. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107879 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-08Remove references to INSERT_SUBREG after de-SSA.Jakob Stoklund Olesen
Fix X86InstrInfo::convertToThreeAddressWithLEA to generate COPY instead of INSERT_SUBREG. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107878 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-07Fix more places assuming subregisters have live intervalsJakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107780 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-07Revert "Remove references to INSERT_SUBREG after de-SSA" r107725.Jakob Stoklund Olesen
Buildbot breakage. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107744 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-06Remove references to INSERT_SUBREG after de-SSAJakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107732 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-06One more case assuming that subregs have live ranges.Jakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107700 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-06Fix buildbot breakage where a def is missing.Jakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107698 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-06Be more forgiving when calculating alias interference for physreg coalescing.Jakob Stoklund Olesen
It is OK for an alias live range to overlap if there is a copy to or from the physical register. CoalescerPair can work out if the copy is coalescable independently of the alias. This means that we can join with the actual destination interval instead of using the getOrigDstReg() hack. It is no longer necessary to merge clobber ranges into subregisters. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107695 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-03Detect and handle COPY in many places.Jakob Stoklund Olesen
This code is transitional, it will soon be possible to eliminate isExtractSubreg, isInsertSubreg, and isMoveInstr in most places. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107547 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-30Use skipInstruction() as a simpler way of iterating over instructions using ↵Jakob Stoklund Olesen
SrcReg git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107234 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-28After physreg coalescing, physical registers might not have live ranges whereJakob Stoklund Olesen
you would expect. Don't assert on that case, just give up. This fixes PR7513. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107046 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-25Don't track kills in VNInfo. Use interval ends instead.Jakob Stoklund Olesen
The VNInfo.kills vector was almost unused except for all the code keeping it updated. The few places using it were easily rewritten to check for interval ends instead. The two new methods LiveInterval::killedAt and killedInRange are replacements. This brings us down to 3 independent data structures tracking kills. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106905 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-25We should remove the live range from the destination register only if *all* defsBill Wendling
are dead, not just the def of this register. I.e., a register could be dead, but it's subreg isn't. Testcase to follow with a subsequent patch. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106878 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-24Teach AdjustCopiesBackFrom to also use CoalescerPair to identify compatible ↵Jakob Stoklund Olesen
copies. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106780 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-24Replace a big gob of old coalescer logic with the new CoalescerPair class.Jakob Stoklund Olesen
CoalescerPair can determine if a copy can be coalesced, and which register gets merged away. The old logic in SimpleRegisterCoalescing had evolved into something a bit too convoluted. This second attempt fixes some crashes that only occurred Linux. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106769 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-24Revert "Replace a big gob of old coalescer logic with the new CoalescerPair ↵Jakob Stoklund Olesen
class." Whiny buildbots. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106710 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-24Replace a big gob of old coalescer logic with the new CoalescerPair class.Jakob Stoklund Olesen
CoalescerPair can determine if a copy can be coalesced, and which register gets merged away. The old logic in SimpleRegisterCoalescing had evolved into something a bit too convoluted. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106701 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-22Remove the SimpleJoin optimization from SimpleRegisterCoalescing.Jakob Stoklund Olesen
Measurements show that it does not speed up coalescing, so there is no reason the keep the added complexity around. Also clean out some unused methods and static functions. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106548 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-15Fix an exotic bug that only showed up in an internal test case.Jakob Stoklund Olesen
SimpleRegisterCoalescing::JoinIntervals() uses CoalescerPair to determine if a copy is coalescable, and in very rare cases it can return true where LHS is not live - the coalescable copy can come from an alias of the physreg in LHS. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106021 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-15Add CoalescerPair helper class.Jakob Stoklund Olesen
Given a copy instruction, CoalescerPair can determine which registers to coalesce in order to eliminate the copy. It deals with all the subreg fun to determine a tuple (DstReg, SrcReg, SubIdx) such that: - SrcReg is a virtual register that will disappear after coalescing. - DstReg is a virtual or physical register whose live range will be extended. - SubIdx is 0 when DstReg is a physical register. - SrcReg can be joined with DstReg:SubIdx. CoalescerPair::isCoalescable() determines if another copy instruction is compatible with the same tuple. This fixes some NEON miscompilations where shuffles are getting coalesced as if they were copies. The CoalescerPair class will replace a lot of the spaghetti logic in JoinCopy later. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@105997 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-02Add full register <imp-def> operands when the coalescer is creating partialJakob Stoklund Olesen
register updates. These operands tell the spiller that the other parts of the partially defined register are don't-care, and a reload is not necessary. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@105361 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-02Slightly change the meaning of the reMaterialize target hook when the originalJakob Stoklund Olesen
instruction defines subregisters. Any existing subreg indices on the original instruction are preserved or composed with the new subreg index. Also substitute multiple operands mentioning the original register by using the new MachineInstr::substituteRegister() function. This is necessary because there will soon be <imp-def> operands added to non read-modify-write partial definitions. This instruction: %reg1234:foo = FLAP %reg1234<imp-def> will reMaterialize(%reg3333, bar) like this: %reg3333:bar-foo = FLAP %reg333:bar<imp-def> Finally, replace the TargetRegisterInfo pointer argument with a reference to indicate that it cannot be NULL. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@105358 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-01Properly compose subregister indices when coalescing.Jakob Stoklund Olesen
The comment about ordering of subreg indices is no longer true. This exposed a bug in the new substVirtReg method that is also fixed. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@105294 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-25Disable invalid coalescer assertion.Jakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104574 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-21- Change MachineInstr::findRegisterDefOperandIdx so it can also look for defsEvan Cheng
that are aliases of the specified register. - Rename modifiesRegister to definesRegister since it's looking a def of the specific register or one of its super-registers. It's not looking for def of a sub-register or alias that could change the specified register. - Added modifiesRegister to look for defs of aliases. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104377 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-18Fix a crash when debugging the coalescer. DebugValue instructions are notBob Wilson
in the coalescer's instruction map. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104086 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-11It's not safe eliminate copies where src and dst have different sub-register ↵Evan Cheng
indices. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103450 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-06Fixes a coalescer bug that caused llc to crash on 2009-11-30-LiveVariablesBug.llEvan Cheng
with the fix in 103157. %reg1039:1<def> = VMOVS %S1<kill>, pred:14, pred:%reg0 is not coalescable since none of the super-registers of S1 are in reg1039's register class: DPR_VFP2. But it is still a legal copy instruction so it should not assert. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103170 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-03Check that subregisters don't have independent values in ↵Jakob Stoklund Olesen
RemoveCopyByCommutingDef(). This fixes PR6941. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102970 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-30Don't use floating point in SimpleRegisterCoalescing.Jakob Stoklund Olesen
Rounding differences causes tests to fail on Linux. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102729 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-29Reject really weird coalescer case when trying to merge identical subregistersJakob Stoklund Olesen
of different register classes. e.g. %reg1048:3<def> = EXTRACT_SUBREG %RAX<kill>, 3 Where %reg1048 is a GR32 register. This is not impossible to handle, but it is pretty hard and very rare. This should unbreak the dragonegg builder. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102672 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-29Fix typos in assertion strings.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102666 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-29Slightly verboser debug spew from coalescerJakob Stoklund Olesen
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102663 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-28Recompute kill flags from live intervals after coalescing instead of trying toJakob Stoklund Olesen
update them. Computing kill flags is notoriously difficult, and the coalescer would get it wrong sometimes, and it would completely skip physical registers. Now we simply remove kill flags based on the live intervals after coalescing. This is a few percent slower, but now we get correct kill flags for physical registers after coalescing. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102510 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-21Do not try to optimize a copy that has already been marked for deletion.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102027 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-21- Clean up some crappy code which deals with coalescing of copies which look atEvan Cheng
extract_subreg / insert_subreg, etc. - Add support for more aggressive insert_subreg coalescing. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101971 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-08Coalescer should not delete copy instructions whose defs are partially dead. ↵Evan Cheng
e.g. %RDI<def,dead> = MOV64rr %RAX<kill>, %EDI<imp-def> git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100804 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-26Try trivial remat before the coalescer gives up on a vr / physreg coalescing ↵Evan Cheng
for fear of tying up a physical register. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99575 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-25Code clean up.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99544 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-25Remove an unused option.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99537 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-25Avoid being influenced by dbg_value instructions.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99465 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-21Free SavedLI even if SimpleRegisterCoalescing::JoinCopy() returns early.Jeffrey Yasskin
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99113 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-18Revert "Change coalescer complexity from N^2 to N logN by changing one letter."Jakob Stoklund Olesen
This reverts commit 98776. It broke the llvm-gcc boot strap. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98784 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-17Change coalescer complexity from N^2 to N logN by changing one letter.Jakob Stoklund Olesen
Remove ugly hack that aborted the coalescer before using N^2 time. This affects functions with very complicated live intervals for physical registers, i.e. functions with thousands of function calls. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98776 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-11The check for coalescing a virtual register to a physical register, e.g.Evan Cheng
cl = EXTRACT_SUBREG reg1024, 1, is overly conservative. It should check for overlaps of vr's live interval with the super registers of the physical register (ECX in this case) and let JoinIntervals() handle checking the coalescing feasibility against the physical register (cl in this case). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98251 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-09Disable physical register coalescing when the number of live ranges for theJakob Stoklund Olesen
physreg becomes ridiculously high. std::upper_bound may be log(N), but for sufficiently large live intervals, it becomes log(N)*cachemiss = a long long time. This patch improves coalescer time by 4500x for a function with 20000 function calls. The generated code is different, but not significantly worse - the allocator hints are almost as good as physreg coalescing anyway. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98023 91177308-0d34-0410-b5e6-96231b3b80d8