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path: root/lib/CodeGen/LowerSubregs.cpp
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2009-08-08Remove RegisterScavenger::isSuperRegUsed(). This completely reverses the ↵Jakob Stoklund Olesen
mistaken commit r77904. Now there is no special treatment of instructions that redefine part of a super-register. Instead, the super-register is marked with <imp-use,kill> and <imp-def>. For instance, from LowerSubregs on ARM: subreg: CONVERTING: %Q1<def> = INSERT_SUBREG %Q1<undef>, %D1<kill>, 5 subreg: %D2<def> = FCPYD %D1<kill>, 14, %reg0, %Q1<imp-def> subreg: CONVERTING: %Q1<def> = INSERT_SUBREG %Q1, %D0<kill>, 6 subreg: %D3<def> = FCPYD %D0<kill>, 14, %reg0, %Q1<imp-use,kill>, %Q1<imp-def> git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78466 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-05Turn some insert_subreg, extract_subreg, subreg_to_reg into implicit_defs.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78151 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-05One more. Transfer kill of the larger register when lowering an EXTRACT_SUBREG.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78145 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-05One more place where subreg lowering forgot to transfer undefness.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78144 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-05If the insert_subreg source is <undef>, insert an implicit_def instead of a ↵Evan Cheng
copy. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78141 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-04LowerSubregsInstructionPass::LowerExtract should not extend the live range ↵Jakob Stoklund Olesen
of registers. When LowerExtract eliminates an EXTRACT_SUBREG with a kill flag, it moves the kill flag to the place where the sub-register is killed. This can accidentally overlap with the use of a sibling sub-register, and we have trouble. In the test case we have this code: Live Ins: %R0 %R1 %R2 %R2L<def> = EXTRACT_SUBREG %R2<kill>, 1 %R2H<def> = LOAD16fi <fi#-1>, 0, Mem:LD(2,4) [FixedStack-1 + 0] %R1L<def> = EXTRACT_SUBREG %R1<kill>, 1 %R0L<def> = EXTRACT_SUBREG %R0<kill>, 1 %R0H<def> = ADD16 %R2H<kill>, %R2L<kill>, %AZ<imp-def>, %AN<imp-def>, %AC0<imp-def>, %V<imp-def>, %VS<imp-def> subreg: CONVERTING: %R2L<def> = EXTRACT_SUBREG %R2<kill>, 1 subreg: eliminated! subreg: killed here: %R0H<def> = ADD16 %R2H, %R2L, %R2<imp-use,kill>, %AZ<imp-def>, %AN<imp-def>, %AC0<imp-def>, %V<imp-def>, %VS<imp-def> The kill flag on %R2 is moved to the last instruction, and the live range overlaps with the definition of %R2H: *** Bad machine code: Redefining a live physical register *** - function: f - basic block: 0x18358c0 (#0) - instruction: %R2H<def> = LOAD16fi <fi#-1>, 0, Mem:LD(2,4) [FixedStack-1 + 0] Register R2H was defined but already live. The fix is to replace EXTRACT_SUBREG with IMPLICIT_DEF instead of eliminating it completely: subreg: CONVERTING: %R2L<def> = EXTRACT_SUBREG %R2<kill>, 1 subreg: replace by: %R2L<def> = IMPLICIT_DEF %R2<kill> Note that these IMPLICIT_DEF instructions survive to the asm output. It is necessary to fix the stack-color-with-reg test case because of that. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78093 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-03Fix Bug 4657: register scavenger asserts with subreg loweringJakob Stoklund Olesen
When LowerSubregsInstructionPass::LowerInsert eliminates an INSERT_SUBREG instriction because it is an identity copy, make sure that the same registers are alive before and after the elimination. When the super-register is marked <undef> this requires inserting an IMPLICIT_DEF instruction to make sure the super register is live. Fix a related bug where a kill flag on the inserted sub-register was not transferred properly. Finally, clear the undef flag in MachineInstr::addRegisterKilled. Undef implies dead and kill implies live, so they cant both be valid. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77989 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-31Use setPreservesAll and setPreservesCFG in CodeGen passes.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77754 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-25More migration to raw_ostream, the water has dried up around the iostream hole.Daniel Dunbar
- Some clients which used DOUT have moved to DEBUG. We are deprecating the "magic" DOUT behavior which avoided calling printing functions when the statement was disabled. In addition to being unnecessary magic, it had the downside of leaving code in -Asserts builds, and of hiding potentially unnecessary computations. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77019 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-16Let RegisterInfo decide whether it can emit cross-class copy or notAnton Korobeynikov
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75955 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-23Do not fold away subreg_to_reg if the source register has a sub-register ↵Evan Cheng
index. That means the source register is taking a sub-register of a larger register. e.g. On x86 %RAX<def> = ... %RAX<def> = SUBREG_TO_REG 0, %EAX:3<kill>, 3 The first def is defining RAX, not EAX so the top bits were not zero-extended. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67511 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-18Teach LowerSubregs to preserve kill/dead information when loweringDan Gohman
subreg instructions. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61220 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-18Make LowerSubregs' debug output for EXTRACT_SUBREG consistent withDan Gohman
that of INSERT_SUBREG and SUBREG_TO_REG. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61218 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-18Fix a copy+pasto in an assertion message.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61217 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-18Fix indentation level.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61216 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-21Silence unused variable warnings.Devang Patel
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59841 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-03Switch the MachineOperand accessors back to the short names likeDan Gohman
isReg, etc., from isRegister, etc. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57006 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-24Give LowerSubregs.cpp a top-level description.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56596 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-22Instead of setPreservesAll, just mark them preseving machine loop info and ↵Evan Cheng
machine dominators. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56475 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-22Mark several codegen passes as preserving all analysis.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56469 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-04Tidy up several unbeseeming casts from pointer to intptr_t.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55779 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-20Fix indentation.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55049 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-07Re-enable elimination of unnecessary SUBREG_TO_REG instructions inDan Gohman
LowerSubregs, and fix an x86-64 isel bug that this exposed. SUBREG_TO_REG for x86-64 implicit zero extension is only safe for isel to generate when the source is known to always have zeros in the high 32 bits. The EXTRACT_SUBREG instruction does not clear the high 32 bits. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54444 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-17Re-introduce LeakDetector support for MachineInstrs and MachineBasicBlocks.Dan Gohman
Fix a leak that this turned up in LowerSubregs.cpp. And, comment a leak in LiveIntervalAnalysis.cpp. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53746 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-17It's not safe to remove SUBREG_TO_REG that looks like identity copies, e.g. ↵Evan Cheng
movl %eax, %eax on x86-64 actually does a zero-extend. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52421 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-16Do not issue identity copies.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52373 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-04Revert this.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51949 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-04LowerSubregs should not clobber any analysis.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51933 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-16Make insert_subreg a two-address instruction, vastly simplifying ↵Christopher Lamb
LowerSubregs pass. Add a new TII, subreg_to_reg, which is like insert_subreg except that it takes an immediate implicit value to insert into rather than a register. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48412 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-13Get rid of a pseudo instruction and replace it with subreg based operation ↵Christopher Lamb
on real instructions, ridding the asm printers of the hack used to do this previously. In the process, update LowerSubregs to be careful about eliminating copies that have side affects. Note: the coalescer will have to be careful about this too, when it starts coalescing insert_subreg nodes. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48329 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-11Recommitting parts of r48130. These do not appear to cause the observed ↵Christopher Lamb
failures. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48223 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-11Use TargetRegisterInfo::getPhysicalRegisterRegClass. Remove duplicated code.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48221 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-10Revert 48125, 48126, and 48130 for now to unbreak some x86-64 tests.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48167 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-10Allow insert_subreg into implicit, target-specific values. Christopher Lamb
Change insert/extract subreg instructions to be able to be used in TableGen patterns. Use the above features to reimplement an x86-64 pseudo instruction as a pattern. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48130 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-10Rename MRegisterInfo to TargetRegisterInfo.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46930 91177308-0d34-0410-b5e6-96231b3b80d8
2007-12-31Move copyRegToReg from MRegisterInfo to TargetInstrInfo. This is part of theOwen Anderson
Machine-level API cleanup instigated by Chris. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45470 91177308-0d34-0410-b5e6-96231b3b80d8
2007-12-31Rename SSARegMap -> MachineRegisterInfo in keeping with the idea Chris Lattner
that "machine" classes are used to represent the current state of the code being compiled. Given this expanded name, we can start moving other stuff into it. For now, move the UsedPhysRegs and LiveIn/LoveOuts vectors from MachineFunction into it. Update all the clients to match. This also reduces some needless #includes, such as MachineModuleInfo from MachineFunction. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45467 91177308-0d34-0410-b5e6-96231b3b80d8
2007-12-29Remove attribution from file headers, per discussion on llvmdev.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45418 91177308-0d34-0410-b5e6-96231b3b80d8
2007-10-23isSubRegOf() is a dup of isSubRegister.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43249 91177308-0d34-0410-b5e6-96231b3b80d8
2007-09-26Allow copyRegToReg to emit cross register classes copies.Evan Cheng
Tested with "make check"! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42346 91177308-0d34-0410-b5e6-96231b3b80d8
2007-09-14Remove isReg, isImm, and isMBB, and change all their users to use Dan Gohman
isRegister, isImmediate, and isMachineBasicBlock, which are equivalent, and more popular. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41958 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-10Move isSubRegOf into MRegisterInfo. Fix a missed move elimination in ↵Christopher Lamb
LowerSubregs and add more debugging output there. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41005 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-06Implement review feedback. No functionality change.Christopher Lamb
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40863 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-26Add a MachineFunction pass, which runs post register allocation, that turns ↵Christopher Lamb
subreg insert/extract instruction into register copies. This ensures correct code gen if the coalescer isn't able to remove all subreg instructions. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40521 91177308-0d34-0410-b5e6-96231b3b80d8
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