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path: root/lib/Target/ARM/ARMHazardRecognizer.cpp
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* Don't cache the instruction and register info from the TargetMachine, becauseBill Wendling2013-06-07
| | | | | | | the internals of TargetMachine could change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183488 91177308-0d34-0410-b5e6-96231b3b80d8
* This patch introduces A15 as a target in LLVM.Silviu Baranga2012-09-13
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163803 91177308-0d34-0410-b5e6-96231b3b80d8
* - Add MachineInstrBundle.h and MachineInstrBundle.cpp. This includes a functionEvan Cheng2011-12-14
| | | | | | | | | | | to finalize MI bundles (i.e. add BUNDLE instruction and computing register def and use lists of the BUNDLE instruction) and a pass to unpack bundles. - Teach more of MachineBasic and MachineInstr methods to be bundle aware. - Switch Thumb2 IT block to MI bundles and delete the hazard recognizer hack to prevent IT blocks from being broken apart. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146542 91177308-0d34-0410-b5e6-96231b3b80d8
* Add bundle aware API for querying instruction properties and switch the codeEvan Cheng2011-12-07
| | | | | | | | | | | | | | | generator to it. For non-bundle instructions, these behave exactly the same as the MC layer API. For properties like mayLoad / mayStore, look into the bundle and if any of the bundled instructions has the property it would return true. For properties like isPredicable, only return true if *all* of the bundled instructions have the property. For properties like canFoldAsLoad, isCompare, conservatively return false for bundles. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146026 91177308-0d34-0410-b5e6-96231b3b80d8
* - Rename TargetInstrDesc, TargetOperandInfo to MCInstrDesc and MCOperandInfo andEvan Cheng2011-06-28
| | | | | | | | | sink them into MC layer. - Added MCInstrInfo, which captures the tablegen generated static data. Chang TargetInstrInfo so it's based off MCInstrInfo. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134021 91177308-0d34-0410-b5e6-96231b3b80d8
* This patch combines several changes from Evan Cheng for rdar://8659675.Bob Wilson2011-04-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Making use of VFP / NEON floating point multiply-accumulate / subtraction is difficult on current ARM implementations for a few reasons. 1. Even though a single vmla has latency that is one cycle shorter than a pair of vmul + vadd, a RAW hazard during the first (4? on Cortex-a8) can cause additional pipeline stall. So it's frequently better to single codegen vmul + vadd. 2. A vmla folowed by a vmul, vmadd, or vsub causes the second fp instruction to stall for 4 cycles. We need to schedule them apart. 3. A vmla followed vmla is a special case. Obvious issuing back to back RAW vmla + vmla is very bad. But this isn't ideal either: vmul vadd vmla Instead, we want to expand the second vmla: vmla vmul vadd Even with the 4 cycle vmul stall, the second sequence is still 2 cycles faster. Up to now, isel simply avoid codegen'ing fp vmla / vmls. This works well enough but it isn't the optimial solution. This patch attempts to make it possible to use vmla / vmls in cases where it is profitable. A. Add missing isel predicates which cause vmla to be codegen'ed. B. Make sure the fmul in (fadd (fmul)) has a single use. We don't want to compute a fmul and a fmla. C. Add additional isel checks for vmla, avoid cases where vmla is feeding into fp instructions (except for the #3 exceptional case). D. Add ARM hazard recognizer to model the vmla / vmls hazards. E. Add a special pre-regalloc case to expand vmla / vmls when it's likely the vmla / vmls will trigger one of the special hazards. Enable these fp vmlx codegen changes for Cortex-A9. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129775 91177308-0d34-0410-b5e6-96231b3b80d8
* VFP single precision arith instructions can go down to NEON pipeline, but on ↵Evan Cheng2011-02-22
| | | | | | Cortex-A8 only. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126238 91177308-0d34-0410-b5e6-96231b3b80d8
* Clean up ARM subtarget code by using Triple ADT.Evan Cheng2011-01-11
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123276 91177308-0d34-0410-b5e6-96231b3b80d8
* Various bits of framework needed for precise machine-level selectionAndrew Trick2010-12-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | DAG scheduling during isel. Most new functionality is currently guarded by -enable-sched-cycles and -enable-sched-hazard. Added InstrItineraryData::IssueWidth field, currently derived from ARM itineraries, but could be initialized differently on other targets. Added ScheduleHazardRecognizer::MaxLookAhead to indicate whether it is active, and if so how many cycles of state it holds. Added SchedulingPriorityQueue::HasReadyFilter to allowing gating entry into the scheduler's available queue. ScoreboardHazardRecognizer now accesses the ScheduleDAG in order to get information about it's SUnits, provides RecedeCycle for bottom-up scheduling, correctly computes scoreboard depth, tracks IssueCount, and considers potential stall cycles when checking for hazards. ScheduleDAGRRList now models machine cycles and hazards (under flags). It tracks MinAvailableCycle, drives the hazard recognizer and priority queue's ready filter, manages a new PendingQueue, properly accounts for stall cycles, etc. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122541 91177308-0d34-0410-b5e6-96231b3b80d8
* Generalize PostRAHazardRecognizer so it can be used in any pass forAndrew Trick2010-12-08
| | | | | | | | | both forward and backward scheduling. Rename it to ScoreboardHazardRecognizer (Scoreboard is one word). Remove integer division from the scoreboard's critical path. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121274 91177308-0d34-0410-b5e6-96231b3b80d8
* Making use of VFP / NEON floating point multiply-accumulate / subtraction isEvan Cheng2010-12-05
difficult on current ARM implementations for a few reasons. 1. Even though a single vmla has latency that is one cycle shorter than a pair of vmul + vadd, a RAW hazard during the first (4? on Cortex-a8) can cause additional pipeline stall. So it's frequently better to single codegen vmul + vadd. 2. A vmla folowed by a vmul, vmadd, or vsub causes the second fp instruction to stall for 4 cycles. We need to schedule them apart. 3. A vmla followed vmla is a special case. Obvious issuing back to back RAW vmla + vmla is very bad. But this isn't ideal either: vmul vadd vmla Instead, we want to expand the second vmla: vmla vmul vadd Even with the 4 cycle vmul stall, the second sequence is still 2 cycles faster. Up to now, isel simply avoid codegen'ing fp vmla / vmls. This works well enough but it isn't the optimial solution. This patch attempts to make it possible to use vmla / vmls in cases where it is profitable. A. Add missing isel predicates which cause vmla to be codegen'ed. B. Make sure the fmul in (fadd (fmul)) has a single use. We don't want to compute a fmul and a fmla. C. Add additional isel checks for vmla, avoid cases where vmla is feeding into fp instructions (except for the #3 exceptional case). D. Add ARM hazard recognizer to model the vmla / vmls hazards. E. Add a special pre-regalloc case to expand vmla / vmls when it's likely the vmla / vmls will trigger one of the special hazards. Work in progress, only A+B are enabled. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120960 91177308-0d34-0410-b5e6-96231b3b80d8