Revision tags: llvmorg-18.1.8, llvmorg-18.1.7, llvmorg-18.1.6, llvmorg-18.1.5, llvmorg-18.1.4, llvmorg-18.1.3, llvmorg-18.1.2, llvmorg-18.1.1, llvmorg-18.1.0, llvmorg-18.1.0-rc4, llvmorg-18.1.0-rc3, llvmorg-18.1.0-rc2, llvmorg-18.1.0-rc1, llvmorg-19-init, llvmorg-17.0.6, llvmorg-17.0.5, llvmorg-17.0.4, llvmorg-17.0.3, llvmorg-17.0.2, llvmorg-17.0.1, llvmorg-17.0.0, llvmorg-17.0.0-rc4, llvmorg-17.0.0-rc3, llvmorg-17.0.0-rc2, llvmorg-17.0.0-rc1, llvmorg-18-init, llvmorg-16.0.6, llvmorg-16.0.5, llvmorg-16.0.4, llvmorg-16.0.3, llvmorg-16.0.2, llvmorg-16.0.1, llvmorg-16.0.0, llvmorg-16.0.0-rc4, llvmorg-16.0.0-rc3, llvmorg-16.0.0-rc2, llvmorg-16.0.0-rc1, llvmorg-17-init, llvmorg-15.0.7, llvmorg-15.0.6, llvmorg-15.0.5, llvmorg-15.0.4, llvmorg-15.0.3, working, llvmorg-15.0.2, llvmorg-15.0.1, llvmorg-15.0.0, llvmorg-15.0.0-rc3, llvmorg-15.0.0-rc2, llvmorg-15.0.0-rc1, llvmorg-16-init |
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#
9ff10a0d |
| 12-Jul-2022 |
Igor Kudrin <ikudrin@accesssoftek.com> |
[NVPTX] Add missing pass names
Differential Revision:
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Revision tags: llvmorg-14.0.6, llvmorg-14.0.5, llvmorg-14.0.4, llvmorg-14.0.3, llvmorg-14.0.2, llvmorg-14.0.1, llvmorg-14.0.0, llvmorg-14.0.0-rc4, llvmorg-14.0.0-rc3, llvmorg-14.0.0-rc2, llvmorg-14.0.0-rc1, llvmorg-15-init, llvmorg-13.0.1, llvmorg-13.0.1-rc3, llvmorg-13.0.1-rc2, llvmorg-13.0.1-rc1 |
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#
bd4dad87 |
| 07-Oct-2021 |
Jack Andersen <jackoalan@gmail.com> |
[MachineInstr] Move MIParser's DBG_VALUE RegState::Debug invariant into MachineInstr::addOperand
Based on the reasoning of D53903, register operands of DBG_VALUE are invariably treated as RegState::
[MachineInstr] Move MIParser's DBG_VALUE RegState::Debug invariant into MachineInstr::addOperand
Based on the reasoning of D53903, register operands of DBG_VALUE are invariably treated as RegState::Debug operands. This change enforces this invariant as part of MachineInstr::addOperand so that all passes emit this flag consistently.
RegState::Debug is inconsistently set on DBG_VALUE registers throughout LLVM. This runs the risk of a filtering iterator like MachineRegisterInfo::reg_nodbg_iterator to process these operands erroneously when not parsed from MIR sources.
This issue was observed in the development of the llvm-mos fork which adds a backend that relies on physical register operands much more than existing targets. Physical RegUnit 0 has the same numeric encoding as $noreg (indicating an undef for DBG_VALUE). Allowing debug operands into the machine scheduler correlates $noreg with RegUnit 0 (i.e. a collision of register numbers with different zero semantics). Eventually, this causes an assert where DBG_VALUE instructions are prohibited from participating in live register ranges.
Reviewed By: MatzeB, StephenTozer
Differential Revision: https://reviews.llvm.org/D110105
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Revision tags: llvmorg-13.0.0, llvmorg-13.0.0-rc4, llvmorg-13.0.0-rc3, llvmorg-13.0.0-rc2, llvmorg-13.0.0-rc1, llvmorg-14-init, llvmorg-12.0.1, llvmorg-12.0.1-rc4, llvmorg-12.0.1-rc3, llvmorg-12.0.1-rc2, llvmorg-12.0.1-rc1, llvmorg-12.0.0, llvmorg-12.0.0-rc5, llvmorg-12.0.0-rc4 |
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#
a9968c0a |
| 15-Mar-2021 |
Tomas Matheson <tomas.matheson@arm.com> |
[NFC][CodeGen] Tidy up TargetRegisterInfo stack realignment functions
Currently needsStackRealignment returns false if canRealignStack returns false. This means that the behavior of needsStackRealig
[NFC][CodeGen] Tidy up TargetRegisterInfo stack realignment functions
Currently needsStackRealignment returns false if canRealignStack returns false. This means that the behavior of needsStackRealignment does not correspond to it's name and description; a function might need stack realignment, but if it is not possible then this function returns false. Furthermore, needsStackRealignment is not virtual and therefore some backends have made use of canRealignStack to indicate whether a function needs stack realignment.
This patch attempts to clarify the situation by separating them and introducing new names:
- shouldRealignStack - true if there is any reason the stack should be realigned
- canRealignStack - true if we are still able to realign the stack (e.g. we can still reserve/have reserved a frame pointer)
- hasStackRealignment = shouldRealignStack && canRealignStack (not target customisable)
Targets can now override shouldRealignStack to indicate that stack realignment is required.
This change will make it easier in a future change to handle the case where we need to realign the stack but can't do so (for example when the register allocator creates an aligned spill after the frame pointer has been eliminated).
Differential Revision: https://reviews.llvm.org/D98716
Change-Id: Ib9a4d21728bf9d08a545b4365418d3ffe1af4d87
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Revision tags: llvmorg-12.0.0-rc3 |
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#
f6774130 |
| 04-Mar-2021 |
Stephen Tozer <Stephen.Tozer@Sony.com> |
Reapply "[DebugInfo] Add new instruction and DIExpression operator for variadic debug values"
Rewrites test to use correct architecture triple; fixes incorrect reference in SourceLevelDebugging doc
Reapply "[DebugInfo] Add new instruction and DIExpression operator for variadic debug values"
Rewrites test to use correct architecture triple; fixes incorrect reference in SourceLevelDebugging doc; simplifies `spillReg` behaviour so as to not be dependent on changes elsewhere in the patch stack.
This reverts commit d2000b45d033c06dc7973f59909a0ad12887ff51.
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#
d2000b45 |
| 04-Mar-2021 |
Stephen Tozer <Stephen.Tozer@Sony.com> |
Revert "[DebugInfo] Add new instruction and DIExpression operator for variadic debug values"
This reverts commit d07f106f4a48b6e941266525b6f7177834d7b74e.
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Revision tags: llvmorg-12.0.0-rc2, llvmorg-11.1.0, llvmorg-11.1.0-rc3, llvmorg-12.0.0-rc1, llvmorg-13-init, llvmorg-11.1.0-rc2, llvmorg-11.1.0-rc1, llvmorg-11.0.1, llvmorg-11.0.1-rc2, llvmorg-11.0.1-rc1, llvmorg-11.0.0, llvmorg-11.0.0-rc6, llvmorg-11.0.0-rc5, llvmorg-11.0.0-rc4, llvmorg-11.0.0-rc3 |
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#
d07f106f |
| 11-Sep-2020 |
gbtozers <stephen.tozer@sony.com> |
[DebugInfo] Add new instruction and DIExpression operator for variadic debug values
This patch adds a new instruction that can represent variadic debug values, DBG_VALUE_VAR. This patch alone covers
[DebugInfo] Add new instruction and DIExpression operator for variadic debug values
This patch adds a new instruction that can represent variadic debug values, DBG_VALUE_VAR. This patch alone covers the addition of the instruction and a set of basic code changes in MachineInstr and a few adjacent areas, but does not correctly handle variadic debug values outside of these areas, nor does it generate them at any point.
The new instruction is similar to the existing DBG_VALUE instruction, with the following differences: the operands are in a different order, any number of values may be used in the instruction following the Variable and Expression operands (these are referred to in code as “debug operands”) and are indexed from 0 so that getDebugOperand(X) == getOperand(X+2), and the Expression in a DBG_VALUE_VAR must use the DW_OP_LLVM_arg operator to pass arguments into the expression.
The new DW_OP_LLVM_arg operator is only valid in expressions appearing in a DBG_VALUE_VAR; it takes a single argument and pushes the debug operand at the index given by the argument onto the Expression stack. For example the sub-expression `DW_OP_LLVM_arg, 0` has the meaning “Push the debug operand at index 0 onto the expression stack.”
Differential Revision: https://reviews.llvm.org/D82363
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#
d57bba7c |
| 04-Nov-2020 |
Sander de Smalen <sander.desmalen@arm.com> |
[SVE] Return StackOffset for TargetFrameLowering::getFrameIndexReference.
To accommodate frame layouts that have both fixed and scalable objects on the stack, describing a stack location or offset u
[SVE] Return StackOffset for TargetFrameLowering::getFrameIndexReference.
To accommodate frame layouts that have both fixed and scalable objects on the stack, describing a stack location or offset using a pointer + uint64_t is not sufficient. For this reason, we've introduced the StackOffset class, which models both the fixed- and scalable sized offsets.
The TargetFrameLowering::getFrameIndexReference is made to return a StackOffset, so that this can be used in other interfaces, such as to eliminate frame indices in PEI or to emit Debug locations for variables on the stack.
This patch is purely mechanical and doesn't change the behaviour of how the result of this function is used for fixed-sized offsets. The patch adds various checks to assert that the offset has no scalable component, as frame offsets with a scalable component are not yet supported in various places.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D90018
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Revision tags: llvmorg-11.0.0-rc2, llvmorg-11.0.0-rc1, llvmorg-12-init, llvmorg-10.0.1, llvmorg-10.0.1-rc4, llvmorg-10.0.1-rc3, llvmorg-10.0.1-rc2 |
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#
539381da |
| 22-Jun-2020 |
stozer <stephen.tozer@sony.com> |
[DebugInfo] Update MachineInstr to help support variadic DBG_VALUE instructions
Following on from this RFC[0] from a while back, this is the first patch towards implementing variadic debug values.
[DebugInfo] Update MachineInstr to help support variadic DBG_VALUE instructions
Following on from this RFC[0] from a while back, this is the first patch towards implementing variadic debug values.
This patch specifically adds a set of functions to MachineInstr for performing operations specific to debug values, and replacing uses of the more general functions where appropriate. The most prevalent of these is replacing getOperand(0) with getDebugOperand(0) for debug-value-specific code, as the operands corresponding to values will no longer be at index 0, but index 2 and upwards: getDebugOperand(x) == getOperand(x+2). Similar replacements have been added for the other operands, along with some helper functions to replace oft-repeated code and operate on a variable number of value operands.
[0] http://lists.llvm.org/pipermail/llvm-dev/2020-February/139376.html<Paste>
Differential Revision: https://reviews.llvm.org/D81852
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Revision tags: llvmorg-10.0.1-rc1 |
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#
2481f26a |
| 07-Apr-2020 |
Matt Arsenault <Matthew.Arsenault@amd.com> |
CodeGen: Use Register in TargetFrameLowering
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Revision tags: llvmorg-10.0.0, llvmorg-10.0.0-rc6, llvmorg-10.0.0-rc5 |
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#
c3df69fa |
| 17-Mar-2020 |
Guillaume Chatelet <gchatelet@google.com> |
[Alignment][NFC] Deprecate getTransientStackAlignment
Summary: This is patch is part of a series to introduce an Alignment type. See this thread for context: http://lists.llvm.org/pipermail/llvm-dev
[Alignment][NFC] Deprecate getTransientStackAlignment
Summary: This is patch is part of a series to introduce an Alignment type. See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html See this patch for the introduction of the type: https://reviews.llvm.org/D64790
Reviewers: courbet
Subscribers: jholewinski, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D76301
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Revision tags: llvmorg-10.0.0-rc4, llvmorg-10.0.0-rc3, llvmorg-10.0.0-rc2, llvmorg-10.0.0-rc1, llvmorg-11-init, llvmorg-9.0.1, llvmorg-9.0.1-rc3, llvmorg-9.0.1-rc2, llvmorg-9.0.1-rc1, llvmorg-9.0.0, llvmorg-9.0.0-rc6, llvmorg-9.0.0-rc5, llvmorg-9.0.0-rc4, llvmorg-9.0.0-rc3 |
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1c18a9cb |
| 21-Aug-2019 |
Guillaume Chatelet <gchatelet@google.com> |
[LLVM][Alignment] Introduce Alignment In MachineFrameInfo
Summary: This is patch is part of a serie to introduce an Alignment type. See this thread for context: http://lists.llvm.org/pipermail/llvm-
[LLVM][Alignment] Introduce Alignment In MachineFrameInfo
Summary: This is patch is part of a serie to introduce an Alignment type. See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html See this patch for the introduction of the type: https://reviews.llvm.org/D64790
Reviewers: jfb
Subscribers: hiraditya, dexonsmith, llvm-commits, courbet
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65800
llvm-svn: 369531
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Revision tags: llvmorg-9.0.0-rc2, llvmorg-9.0.0-rc1, llvmorg-10-init, llvmorg-8.0.1, llvmorg-8.0.1-rc4, llvmorg-8.0.1-rc3, llvmorg-8.0.1-rc2 |
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#
e85bbf56 |
| 20-May-2019 |
Petar Jovanovic <petar.jovanovic@mips.com> |
[DebugInfoMetadata] Refactor DIExpression::prepend constants (NFC)
Refactor DIExpression::With* into a flag enum in order to be less error-prone to use (as discussed on D60866).
Patch by Djordje To
[DebugInfoMetadata] Refactor DIExpression::prepend constants (NFC)
Refactor DIExpression::With* into a flag enum in order to be less error-prone to use (as discussed on D60866).
Patch by Djordje Todorovic.
Differential Revision: https://reviews.llvm.org/D61943
llvm-svn: 361137
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Revision tags: llvmorg-8.0.1-rc1, llvmorg-8.0.0, llvmorg-8.0.0-rc5, llvmorg-8.0.0-rc4, llvmorg-8.0.0-rc3, llvmorg-7.1.0, llvmorg-7.1.0-rc1, llvmorg-8.0.0-rc2, llvmorg-8.0.0-rc1 |
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#
2946cd70 |
| 19-Jan-2019 |
Chandler Carruth <chandlerc@gmail.com> |
Update the file headers across all of the LLVM projects in the monorepo to reflect the new license.
We understand that people may be surprised that we're moving the header entirely to discuss the ne
Update the file headers across all of the LLVM projects in the monorepo to reflect the new license.
We understand that people may be surprised that we're moving the header entirely to discuss the new license. We checked this carefully with the Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM project under our new license, so you will see that the license headers include that license only. Some of our contributors have contributed code under our old license, and accordingly, we have retained a copy of our old license notice in the top-level files in each project and repository.
llvm-svn: 351636
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Revision tags: llvmorg-7.0.1, llvmorg-7.0.1-rc3, llvmorg-7.0.1-rc2, llvmorg-7.0.1-rc1 |
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#
0f2fe4f1 |
| 25-Oct-2018 |
Alexey Bataev <a.bataev@hotmail.com> |
[DEBUG_INFO][NVPTX]Fix processing of DBG_VALUES.
Summary: If the instruction in the eliminateFrameIndex function is a DBG_VALUE instruction, it requires special processing. The frame register is set
[DEBUG_INFO][NVPTX]Fix processing of DBG_VALUES.
Summary: If the instruction in the eliminateFrameIndex function is a DBG_VALUE instruction, it requires special processing. The frame register is set to VRFrame and the offset is based on the object offset. The code is similar to the code used in lib/CodeGen/PrologEpilogInserter.cpp.
Reviewers: tra
Subscribers: jholewinski, llvm-commits
Differential Revision: https://reviews.llvm.org/D53657
llvm-svn: 345269
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Revision tags: llvmorg-7.0.0, llvmorg-7.0.0-rc3, llvmorg-7.0.0-rc2, llvmorg-7.0.0-rc1, llvmorg-6.0.1, llvmorg-6.0.1-rc3, llvmorg-6.0.1-rc2 |
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d34e60ca |
| 14-May-2018 |
Nicola Zaghen <nicola.zaghen@imgtec.com> |
Rename DEBUG macro to LLVM_DEBUG. The DEBUG() macro is very generic so it might clash with other projects. The renaming was done as follows: - git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/
Rename DEBUG macro to LLVM_DEBUG. The DEBUG() macro is very generic so it might clash with other projects. The renaming was done as follows: - git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g' - git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM - Manual change to APInt - Manually chage DOCS as regex doesn't match it.
In the transition period the DEBUG() macro is still present and aliased to the LLVM_DEBUG() one.
Differential Revision: https://reviews.llvm.org/D43624
llvm-svn: 332240
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Revision tags: llvmorg-6.0.1-rc1, llvmorg-5.0.2, llvmorg-5.0.2-rc2, llvmorg-5.0.2-rc1, llvmorg-6.0.0, llvmorg-6.0.0-rc3, llvmorg-6.0.0-rc2, llvmorg-6.0.0-rc1, llvmorg-5.0.1, llvmorg-5.0.1-rc3, llvmorg-5.0.1-rc2 |
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#
b3bde2ea |
| 17-Nov-2017 |
David Blaikie <dblaikie@gmail.com> |
Fix a bunch more layering of CodeGen headers that are in Target
All these headers already depend on CodeGen headers so moving them into CodeGen fixes the layering (since CodeGen depends on Target, n
Fix a bunch more layering of CodeGen headers that are in Target
All these headers already depend on CodeGen headers so moving them into CodeGen fixes the layering (since CodeGen depends on Target, not the other way around).
llvm-svn: 318490
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#
1be62f03 |
| 03-Nov-2017 |
David Blaikie <dblaikie@gmail.com> |
Move TargetFrameLowering.h to CodeGen where it's implemented
This header already includes a CodeGen header and is implemented in lib/CodeGen, so move the header there to match.
This fixes a link er
Move TargetFrameLowering.h to CodeGen where it's implemented
This header already includes a CodeGen header and is implemented in lib/CodeGen, so move the header there to match.
This fixes a link error with modular codegeneration builds - where a header and its implementation are circularly dependent and so need to be in the same library, not split between two like this.
llvm-svn: 317379
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Revision tags: llvmorg-5.0.1-rc1, llvmorg-5.0.0, llvmorg-5.0.0-rc5, llvmorg-5.0.0-rc4, llvmorg-5.0.0-rc3, llvmorg-5.0.0-rc2, llvmorg-5.0.0-rc1, llvmorg-4.0.1, llvmorg-4.0.1-rc3, llvmorg-4.0.1-rc2, llvmorg-4.0.1-rc1, llvmorg-4.0.0, llvmorg-4.0.0-rc4, llvmorg-4.0.0-rc3, llvmorg-4.0.0-rc2, llvmorg-4.0.0-rc1, llvmorg-3.9.1, llvmorg-3.9.1-rc3, llvmorg-3.9.1-rc2, llvmorg-3.9.1-rc1, llvmorg-3.9.0, llvmorg-3.9.0-rc3, llvmorg-3.9.0-rc2, llvmorg-3.9.0-rc1 |
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#
941a705b |
| 28-Jul-2016 |
Matthias Braun <matze@braunis.de> |
MachineFunction: Return reference for getFrameInfo(); NFC
getFrameInfo() never returns nullptr so we should use a reference instead of a pointer.
llvm-svn: 277017
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#
68f499a6 |
| 08-Jul-2016 |
Duncan P. N. Exon Smith <dexonsmith@apple.com> |
NVPTX: Avoid implicit iterator conversions, NFC
Avoid implicit conversions from MachineInstrBundleIterator to MachineInstr* in the NVPTX backend, mainly by preferring MachineInstr& over MachineInstr
NVPTX: Avoid implicit iterator conversions, NFC
Avoid implicit conversions from MachineInstrBundleIterator to MachineInstr* in the NVPTX backend, mainly by preferring MachineInstr& over MachineInstr* when a pointer isn't nullable and using range-based for loops.
There was one piece of questionable code in NVPTXInstrInfo::AnalyzeBranch, where a condition checked a pointer converted from an iterator for nullptr. Since this case is impossible (moreover, the code above guarantees that the iterator is valid), I removed the check when I changed the pointer to a reference.
Despite that case, there should be no functionality change here.
llvm-svn: 274931
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Revision tags: llvmorg-3.8.1, llvmorg-3.8.1-rc1, llvmorg-3.8.0, llvmorg-3.8.0-rc3, llvmorg-3.8.0-rc2, llvmorg-3.8.0-rc1, llvmorg-3.7.1, llvmorg-3.7.1-rc2, llvmorg-3.7.1-rc1 |
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c2d4befb |
| 25-Sep-2015 |
Matthias Braun <matze@braunis.de> |
MachineBasicBlock: Factor out common code into isReturnBlock()
llvm-svn: 248617
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Revision tags: llvmorg-3.7.0, llvmorg-3.7.0-rc4, llvmorg-3.7.0-rc3, studio-1.4, llvmorg-3.7.0-rc2, llvmorg-3.7.0-rc1, llvmorg-3.6.2, llvmorg-3.6.2-rc1 |
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#
f00654e3 |
| 23-Jun-2015 |
Alexander Kornienko <alexfh@google.com> |
Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC)
Apparently, the style needs to be agreed upon first.
llvm-svn: 240390
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70bc5f13 |
| 19-Jun-2015 |
Alexander Kornienko <alexfh@google.com> |
Fixed/added namespace ending comments using clang-tidy. NFC
The patch is generated using this command:
tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \ -checks=-*,llvm-namespace-c
Fixed/added namespace ending comments using clang-tidy. NFC
The patch is generated using this command:
tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \ -checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \ llvm/lib/
Thanks to Eugene Kosov for the original patch!
llvm-svn: 240137
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Revision tags: llvmorg-3.6.1, llvmorg-3.6.1-rc1 |
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#
61b305ed |
| 05-May-2015 |
Quentin Colombet <qcolombet@apple.com> |
[ShrinkWrap] Add (a simplified version) of shrink-wrapping.
This patch introduces a new pass that computes the safe point to insert the prologue and epilogue of the function. The interest is to find
[ShrinkWrap] Add (a simplified version) of shrink-wrapping.
This patch introduces a new pass that computes the safe point to insert the prologue and epilogue of the function. The interest is to find safe points that are cheaper than the entry and exits blocks.
As an example and to avoid regressions to be introduce, this patch also implements the required bits to enable the shrink-wrapping pass for AArch64.
** Context **
Currently we insert the prologue and epilogue of the method/function in the entry and exits blocks. Although this is correct, we can do a better job when those are not immediately required and insert them at less frequently executed places. The job of the shrink-wrapping pass is to identify such places.
** Motivating example **
Let us consider the following function that perform a call only in one branch of a if: define i32 @f(i32 %a, i32 %b) { %tmp = alloca i32, align 4 %tmp2 = icmp slt i32 %a, %b br i1 %tmp2, label %true, label %false
true: store i32 %a, i32* %tmp, align 4 %tmp4 = call i32 @doSomething(i32 0, i32* %tmp) br label %false
false: %tmp.0 = phi i32 [ %tmp4, %true ], [ %a, %0 ] ret i32 %tmp.0 }
On AArch64 this code generates (removing the cfi directives to ease readabilities): _f: ; @f ; BB#0: stp x29, x30, [sp, #-16]! mov x29, sp sub sp, sp, #16 ; =16 cmp w0, w1 b.ge LBB0_2 ; BB#1: ; %true stur w0, [x29, #-4] sub x1, x29, #4 ; =4 mov w0, wzr bl _doSomething LBB0_2: ; %false mov sp, x29 ldp x29, x30, [sp], #16 ret
With shrink-wrapping we could generate: _f: ; @f ; BB#0: cmp w0, w1 b.ge LBB0_2 ; BB#1: ; %true stp x29, x30, [sp, #-16]! mov x29, sp sub sp, sp, #16 ; =16 stur w0, [x29, #-4] sub x1, x29, #4 ; =4 mov w0, wzr bl _doSomething add sp, x29, #16 ; =16 ldp x29, x30, [sp], #16 LBB0_2: ; %false ret
Therefore, we would pay the overhead of setting up/destroying the frame only if we actually do the call.
** Proposed Solution **
This patch introduces a new machine pass that perform the shrink-wrapping analysis (See the comments at the beginning of ShrinkWrap.cpp for more details). It then stores the safe save and restore point into the MachineFrameInfo attached to the MachineFunction. This information is then used by the PrologEpilogInserter (PEI) to place the related code at the right place. This pass runs right before the PEI.
Unlike the original paper of Chow from PLDI’88, this implementation of shrink-wrapping does not use expensive data-flow analysis and does not need hack to properly avoid frequently executed point. Instead, it relies on dominance and loop properties.
The pass is off by default and each target can opt-in by setting the EnableShrinkWrap boolean to true in their derived class of TargetPassConfig. This setting can also be overwritten on the command line by using -enable-shrink-wrap.
Before you try out the pass for your target, make sure you properly fix your emitProlog/emitEpilog/adjustForXXX method to cope with basic blocks that are not necessarily the entry block.
** Design Decisions **
1. ShrinkWrap is its own pass right now. It could frankly be merged into PEI but for debugging and clarity I thought it was best to have its own file. 2. Right now, we only support one save point and one restore point. At some point we can expand this to several save point and restore point, the impacted component would then be: - The pass itself: New algorithm needed. - MachineFrameInfo: Hold a list or set of Save/Restore point instead of one pointer. - PEI: Should loop over the save point and restore point. Anyhow, at least for this first iteration, I do not believe this is interesting to support the complex cases. We should revisit that when we motivating examples.
Differential Revision: http://reviews.llvm.org/D9210
<rdar://problem/3201744>
llvm-svn: 236507
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Revision tags: llvmorg-3.5.2, llvmorg-3.5.2-rc1, llvmorg-3.6.0, llvmorg-3.6.0-rc4, llvmorg-3.6.0-rc3, llvmorg-3.6.0-rc2 |
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3084aff4 |
| 30-Jan-2015 |
Eric Christopher <echristo@gmail.com> |
Migrate a bare getSubtarget call to query the MachineFunction for the target dependent one.
llvm-svn: 227542
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Revision tags: llvmorg-3.6.0-rc1, llvmorg-3.5.1, llvmorg-3.5.1-rc2, llvmorg-3.5.1-rc1, llvmorg-3.5.0, llvmorg-3.5.0-rc4, llvmorg-3.5.0-rc3, llvmorg-3.5.0-rc2 |
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fc6de428 |
| 05-Aug-2014 |
Eric Christopher <echristo@gmail.com> |
Have MachineFunction cache a pointer to the subtarget to make lookups shorter/easier and have the DAG use that to do the same lookup. This can be used in the future for TargetMachine based caching lo
Have MachineFunction cache a pointer to the subtarget to make lookups shorter/easier and have the DAG use that to do the same lookup. This can be used in the future for TargetMachine based caching lookups from the MachineFunction easily.
Update the MIPS subtarget switching machinery to update this pointer at the same time it runs.
llvm-svn: 214838
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