Calling `ToNop` leaves around instructions that are pointless. In
general it is better to remove the instruction completely. That way
other optimizations will not need to look at them.
Fixes https://github.com/KhronosGroup/SPIRV-Tools/issues/1003.
In CCP we should not need to insert Phi nodes because CCP never looks at
loads/stores. This required adjusting two tests that relied on Phi
instructions being inserted. I changed the tests to have the Phi
instructions pre-inserted.
I also added a new test to make sure that CCP does not try to look
through stores and loads.
Finally, given that CCP does not handle loads/stores, it's better to run
mem2reg before it. I've changed the -O/-Os schedules to run local
multi-store elimination before CCP.
Although this is just an efficiency fix for CCP, it is
also working around a bug in Phi insertion. When Phi instructions are
inserted, they are never associated a basic block. This causes a
segfault when the propagator tries to lookup CFG edges when analyzing
Phi instructions.
This addresses review feedback for the CCP implementation (which fixes
https://github.com/KhronosGroup/SPIRV-Tools/issues/889).
This adds more protection around the folding of instructions that would
not be supported by the folder.
Add grammar file for DebugInfo extended instruction set
- Each new operand enum kind in extinst.debuginfo.grammar.json maps
to a new value in spv_operand_type_t.
- Add new concrete enum operand types for DebugInfo
Generate a C header for the DebugInfo extended instruction set
Add table lookup of DebugInfo extended instrutions
Handle the debug info operand types in binary parser,
disassembler, and assembler.
Add DebugInfo round trip tests for assembler, disassembler
Android.mk: Support DebugInfo extended instruction set
The extinst.debuginfo.grammar.json file is currently part of
SPIRV-Tools source.
It contributes operand type enums, so it has to be processed
along with the core grammar files.
We also generate a C header DebugInfo.h.
Add necessary grammar file processing to Android.mk.
This implements the conditional constant propagation pass proposed in
Constant propagation with conditional branches,
Wegman and Zadeck, ACM TOPLAS 13(2):181-210.
The main logic resides in CCPPass::VisitInstruction. Instruction that
may produce a constant value are evaluated with the constant folder. If
they produce a new constant, the instruction is considered interesting.
Otherwise, it's considered varying (for unfoldable instructions) or
just not interesting (when not enough operands have a constant value).
The other main piece of logic is in CCPPass::VisitBranch. This
evaluates the selector of the branch. When it's found to be a known
value, it computes the destination basic block and sets it. This tells
the propagator which branches to follow.
The patch required extensions to the constant manager as well. Instead
of hashing the Constant pointers, this patch changes the constant pool
to hash the contents of the Constant. This allows the lookups to be
done using the actual values of the Constant, preventing duplicate
definitions.
In order to keep track of all of the implicit capabilities as well as
the explicit ones, we will add them all to the feature manager. That is
the object that needs to be queried when checking if a capability is
enabled.
The name of the "HasCapability" function in the module was changed to
make it more obvious that it does not check for implied capabilities.
Keep an spv_context and AssemblyGrammar in IRContext
* changed the way duplicate types are removed to stop copying
instructions
* Reworked RemoveDuplicatesPass::AreTypesSame to use type manager and
type equality
* Reworked TypeManager memory management to store a pool of unique
pointers of types
* removed unique pointers from id map
* fixed instances where free'd memory could be accessed
Changes the set of optimizations done for legalization. While doing
this, I added documentation to explain why we want each optimization.
A new option "--legalize-hlsl" is added so the legalization passes can
be easily run from the command line.
The legalize option implies skip-validation.
A few optimizations are updates to handle code that is suppose to be
using the logical addressing mode, but still has variables that contain
pointers as long as the pointer are to opaque objects. This is called
"relaxed logical addressing".
|Instruction::GetBaseAddress| will check that pointers that are use meet
the relaxed logical addressing rules. Optimization that now handle
relaxed logical addressing instead of logical addressing are:
- aggressive dead-code elimination
- local access chain convert
- local store elimination passes.
When a private variable is used in a single function, it can be
converted to a function scope variable in that function. This adds a
pass that does that. The pass can be enabled using the option
`--private-to-local`.
This transformation allows other transformations to act on these
variables.
Also moved `FindPointerToType` from the inline class to the type manager.
- Test validation success for OpEmitVertex OpEndPrimitive
- Test missing capabilities for primitive instructions
- Primitive instructions require Geometry execution model
@ehsannas had filed an issue against SPIR-V spec, concerning
Image Operands section (3.14):
Sample
A following operand is the sample number of the sample to use. Only
valid with OpImageFetch, OpImageRead, and OpImageWrite.
Relaxing the check to allow OpImageSparseRead and
OpImageSparseFetch to fix failing tests.
types. This allows the lookup of type declaration ids from arbitrarily
constructed types. Users should be cautious when dealing with non-unique
types (structs and potentially pointers) to get the exact id if
necessary.
* Changed the spec composite constant folder to handle ambiguous composites
* Added functionality to create necessary instructions for a type
* Added ability to remove ids from the type manager
This fixes issue #1075
- Mark continue when conditional branch with merge block.
Only mark if merge block is not continue block.
- Handle conditional branch break with preceding merge
Inlining is not setting the parent (function) for each basic block.
This can cause problems for later optimizations. The solution is to set
the parent for each new block just before it is linked into the
function.
include: Add target environment enums for OpenCL 1.2 and 2.0
Validator: Validate OpenCL capabilities
Update validate capabilities to handle embedded profiles
Add test for OpenCL capabilities validation
Update messages to mention the OpenCL profile used
Re-format val_capability_test.cpp
Adds a scalar replacement pass. The pass considers all function scope
variables of composite type. If there are accesses to individual
elements (and it is legal) the pass replaces the variable with a
variable for each composite element and updates all the uses.
Added the pass to -O
Added NumUses and NumUsers to DefUseManager
Added some helper methods for the inst to block mapping in context
Added some helper methods for specific constant types
No longer generate duplicate pointer types.
* Now searches for an existing pointer of the appropriate type instead
of failing validation
* Fixed spec constant extracts
* Addressed changes for review
* Changed RunSinglePassAndMatch to be able to run validation
* current users do not enable it
Added handling of acceptable decorations.
* Decorations are also transfered where appropriate
Refactored extension checking into FeatureManager
* Context now owns a feature manager
* consciously NOT an analysis
* added some test
* fixed some minor issues related to decorates
* added some decorate related tests for scalar replacement
This patch adds a new constant manager class to interface with
analysis::Constant. The new constant manager lives in ir::IRContext
together with the type manager (analysis::TypeManager).
The new analysis::ConstantManager is used by the spec constant folder
and the constant propagator (in progress).
Another cleanup introduced by this patch removes the ID management from
the fold spec constant pass, and ir::IRContext and moves it to
ir::Module. SSA IDs were maintained by IRContext and Module. That's
pointless and leads to mismatch IDs. Fixed by moving all the bookkeeping
to ir::Module.
Adds a pass that looks for redundant instruction in a function, and
removes them. The algorithm is a hash table based value numbering
algorithm that traverses the dominator tree.
This pass removes completely redundant instructions, not partially
redundant ones.
Currently when inlining a call, the name and decorations for the result of the
call is not deleted. This should be changed. Added a test for this as well.
This fixes issue #622.
Commit 8ec62deb2 merged the code from PR #810, but it also re-introduces
code that had been removed in #885.
This patch removes the (now superfluous code).
Support for dominator and post dominator analysis on ir::Functions. This patch contains a DominatorTree class for building the tree and DominatorAnalysis and DominatorAnalysisPass classes for interfacing and caching the built trees.
In DCEInst, it is possible that the same instruction ends up in the
queue multiple times, if the same id is used multiple times in the
same instruction.
The solution is to keep the ids in a set, to ensure no duplication in
the list.
The current method of removing an instruction is to call ToNop. The
problem with this is that it leaves around an instruction that later
passes will look at. We should just delete the instruction.
In MemPass there is a utility routine called DCEInst. It can delete
essentially any instruction, which can invalidate pointers now that they
are actually deleted. The interface was changed to add a call back that
can be used to update any local data structures that contain
ir::Intruction*.
Computing the value numbers on demand, as we do now, can lead to
different results depending on the order in which the users asks for
the value numbers. To make things more stable, we compute them ahead
of time.
Previously we required _PRINT to enable _COLOR, which forbids
outputting colored disassembly into a string in library.
This commit will allow library users to request enabling
ANSI color escape sequences.
This needs custom code since the rules from the extension
are not encoded in the grammar.
Changes are:
- The new group instructions don't require Group capability
when the extension is declared.
- The Reduce, InclusiveScan, ExclusiveScan normally require the Kernel
capability, but don't when the extension is declared.
Fixes https://github.com/KhronosGroup/SPIRV-Tools/issues/991
This should fix#1034. It changes the predicate on operator< to use
label IDs from each block and compares them as std:pair to define a weak
ordering for std::set.
This class implements a generic value propagation algorithm based on the
conditional constant propagation algorithm proposed in
Constant propagation with conditional branches,
Wegman and Zadeck, ACM TOPLAS 13(2):181-210.
The implementation is based on
A Propagation Engine for GCC
Diego Novillo, GCC Summit 2005
http://ols.fedoraproject.org/GCC/Reprints-2005/novillo-Reprint.pdf
The purpose of this implementation is to act as a common framework for any
transformation that needs to propagate values from statements producing new
values to statements using those values.
Re-formatted the source tree with the command:
$ /usr/bin/clang-format -style=file -i \
$(find include source tools test utils -name '*.cpp' -or -name '*.h')
This required a fix to source/val/decoration.h. It was not including
spirv.h, which broke builds when the #include headers were re-ordered by
clang-format.
Removed the check that result type of OpImageRead should be a vector4.
Will reenable/adapt once the spec is clarified on what the right
dimension should be.
These instructions compute their value based the value of the immediate
neighbours of the current fragment. This means the result is not
defined purely by the operands of the instruction.
Replaced representation of uses
* Changed uses from unordered_map<uint32_t, UseList> to
set<pairInstruction*, Instruction*>>
* Replaced GetUses with ForEachUser and ForEachUse functions
* updated passes to use new functions
* partially updated tests
* lots of cleanup still todo
Adding an unique id to Instruction generated by IRContext
Each instruction is given an unique id that can be used for ordering
purposes. The ids are generated via the IRContext.
Major changes:
* Instructions now contain a uint32_t for unique id and a cached context
pointer
* Most constructors have been modified to take a context as input
* unfortunately I cannot remove the default and copy constructors, but
developers should avoid these
* Added accessors to parents of basic block and function
* Removed the copy constructors for BasicBlock and Function and replaced
them with Clone functions
* Reworked BuildModule to return an IRContext owning the built module
* Since all instructions require a context, the context now becomes the
basic unit for IR
* Added a constructor to context to create an owned module internally
* Replaced uses of Instruction's copy constructor with Clone whereever I
found them
* Reworked the linker functionality to perform clones into a different
context instead of moves
* Updated many tests to be consistent with the above changes
* Still need to add new tests to cover added functionality
* Added comparison operators to Instruction
Adding tests for Instruction, IRContext and IR loading
Fixed some header comments for BuildModule
Fixes to get tests passing again
* Reordered two linker steps to avoid use/def problems
* Fixed def/use manager uses in merge return pass
* Added early return for GetAnnotations
* Changed uses of Instruction::ToNop in passes to IRContext::KillInst
Simplifying the uses for some contexts in passes
Creates a pass that removes redundant instructions within the same basic
block. This will be implemented using a hash based value numbering
algorithm.
Added a number of functions that check for the Vulkan descriptor types.
These are used to determine if we are variables are read-only or not.
Implemented a function to check if loads and variables are read-only.
Implemented kernel specific and shader specific versions.
A big change is that the Combinator analysis in ADCE is factored out
into the IRContext as an analysis. This was done because it is being
reused in the value number table.
Add new "short descriptor" algorithm to MARK-V codec.
Add three shader compression models:
lite - fast, poor compression
mid - balanced
max - best compression
Each instruction is given an unique id that can be used for ordering
purposes. The ids are generated via the IRContext.
Major changes:
* Instructions now contain a uint32_t for unique id and a cached context
pointer
* Most constructors have been modified to take a context as input
* unfortunately I cannot remove the default and copy constructors, but
developers should avoid these
* Added accessors to parents of basic block and function
* Removed the copy constructors for BasicBlock and Function and replaced
them with Clone functions
* Reworked BuildModule to return an IRContext owning the built module
* Since all instructions require a context, the context now becomes the
basic unit for IR
* Added a constructor to context to create an owned module internally
* Replaced uses of Instruction's copy constructor with Clone whereever I
found them
* Reworked the linker functionality to perform clones into a different
context instead of moves
* Updated many tests to be consistent with the above changes
* Still need to add new tests to cover added functionality
* Added comparison operators to Instruction
* Added an internal option to LinkerOptions to verify merged ids are
unique
* Added a test for the linker to verify merged ids are unique
* Updated MergeReturnPass to supply a context
* Updated DecorationManager to supply a context for cloned decorations
* Reworked several portions of the def use tests in anticipation of next
set of changes
To make the decoration manger available everywhere, and to reduce the
number of times it needs to be build, I add one the IRContext.
As the same time, I move code that modifies decoration instruction into
the IRContext from mempass and the decoration manager. This will make
it easier to keep everything up to date.
This should take care of issue #928.
Works with current DefUseManager infrastructure.
Added merge return to the standard opts.
Added validation to passes.
Disabled pass for shader capabilty.
This analysis builds a map from instructions to the basic block that
contains them. It is accessed via get_instr_block(). Once built, it is kept
up-to-date by the IRContext, as long as instructions are removed via
KillInst.
I have not yet marked passes that preserve this analysis. I will do it
in a separate change.
Other changes:
- Add documentation about analysis values requirement to be powers of 2.
- Force a re-build of the def-use manager in tests.
- Fix AllPreserveFirstOnlyAfterPassWithChange to use the
DummyPassPreservesFirst pass.
- Fix sentinel value for IRContext::Analysis enum.
- Fix logic for checking if the instr<->block mapping is valid in KillInst.
Fixes issue #728. Currently the inliner is not generating decorations for
inlined code which corresponds to function code which has decorations. An
example of decorations that are relevant: RelaxedPrecision, NoContraction.
The solution is to replicate the decoration during inlining.
Originally the passes that extended from MemPass were those that are
of the def-use manager. I am assuming they would be able to preserve
it because of that.
Added a check to verify consistency of the IRContext. The IRContext
relies on the pass to tell it if something is invalidated.
It is possible that the pass lied. To help identify those situations,
we will check if the valid analyses are correct after each pass.
This will be enabled by default for the debug build, and disabled in the
production build. It can be disabled in the debug build by adding
"-DSPIRV_CHECK_CONTEXT=OFF" to the cmake command.
NFC. This just makes sure every file is formatted following the
formatting definition in .clang-format.
Re-formatted with:
$ clang-format -i $(find source tools include -name '*.cpp')
$ clang-format -i $(find source tools include -name '*.h')
This change will move the instances of the def-use manager to the
IRContext. This allows it to persists across optimization, and does
not have to be rebuilt multiple times.
Added test to ensure that the IRContext is validating and invalidating
the analyses correctly.
This class moves some of the CFG-related functionality into a new
class opt::CFG. There is some other code related to the CFG in the
inliner and in opt::LocalSingleStoreElimPass that should also be moved,
but that require more changes than this pure restructuring.
I will move those bits in a follow-up PR.
Currently, the CFG is computed every time a pass is instantiated, but
this should be later moved to the new IRContext class that @s-perron is
working on.
Other re-factoring:
- Add BasicBlock::ContinueBlockIdIfAny. Re-factored out of MergeBlockIdIfAny
- Rewrite IsLoopHeader in terms of GetLoopMergeInst.
- Run clang-format on some files.
This is the first part of adding the IRContext. This class is meant to
hold the extra data that is build on top of the module that it
owns.
The first part will simply create the IRContext class and get it passed
to the passes in place of the module. For now it does not have any
functionality of its own, but it acts more as a wrapper for the module.
The functions that I added to the IRContext are those that either
traverse the headers or add to them. I did this because we may decide
to have other ways of dealing with these sections (for example adding a
type pool, or use the decoration manager).
I also added the function that add to the header because the IRContext
needs to know when an instruction is added to update other data
structures appropriately.
Note that there is still lots of work that needs to be done. There are
still many places that change the module, and do not inform the context.
That will be the next step.
Mark structured conditional branches live only if one or more instructions
in their associated construct is marked live. After closure, replace dead
structured conditional branches with a branch to its merge and remove
dead blocks.
ADCE: Dead If Elim: Remove duplicate StructuredOrder code
Also generalize ComputeStructuredOrder so that the caller can specify the
root block for the order. Phi insertion uses pseudo_entry_block and adce and
dead branch elim use the first block of the function.
ADCE: Dead If Elim: Pull redundant code out of InsertPhiInstructions
ADCE: Dead If Elim: Encapsulate CFG Cleanup Initialization
ADCE: Dead If Elim: Remove redundant code from ADCE initialization
ADCE: Dead If: Use CFGCleanup to eliminate newly dead blocks
Moved bulk of CFG Cleanup code into MemPass.
This implements two cleanups suggested by @s-perron
(https://github.com/KhronosGroup/SPIRV-Tools/pull/921):
- Move FindNamedOrDecoratedIds() into MemPass::InitializeProcessing().
- Remove FinalizeNextId(). Always call SetIdBound() from
Pass::TakeNextId().
There are a number of users of spriv-opt that are hitting errors
because of stores with different types. In general, this is wrong, but,
in these cases, the types are the exact same except for decorations.
The options is "--relax-store-struct", and it can be used with the
validator or the optimizer.
We assume that if layout information is missing it is consistent. For
example if one struct has a offset of one of its members, and the other
one does not, we will still consider them as being layout compatible.
The problem will be if both struct has and offset decoration for
corresponding members, and the offset are different.
The feature used to improve compression of const integers which were
presumed to be indices. Now obsolete as descriptor-based compression
does this in a more generalized way.
Including a re-factor of common behaviour into class Pass:
The following functions are now in class Pass:
- IsLoopHeader.
- ComputeStructuredOrder
- ComputeStructuredSuccessors (annoyingly, I could not re-factor all
instances of this function, the copy in common_uniform_elim_pass.cpp
is slightly different and fails with the common implementation).
- GetPointeeTypeId
- TakeNextId
- FinalizeNextId
- MergeBlockIdIfAny
This is a NFC (non-functional change)
This change will replace a number of the
std::vector<std::unique_ptr<Instruction>> member of the module to
InstructionList. This is for consistency and to make it easier to
delete instructions that are no longer needed.
Function static non-POD data causes problems with DLL lifetime.
This pull request turns all static info tables into strict POD
tables. Specifically, the capabilities/extensions field of
opcode/operand/extended-instruction table are turned into two
fields, one for the count and the other a pointer to an array of
capabilities/extensions. CapabilitySet/EnumSet are not used in
the static table anymore, but they are still used for checking
inclusion by constructing on the fly, which should be cheap for
the majority cases.
Also moves all these tables into the global namespace to avoid
C++11 function static thread-safe initialization overhead.
Markv codec now receives two optional callbacks:
LogConsumer for internal codec logging
DebugConsumer for testing if encoding->decoding produces the original
results.
We want to run the optimization when using -O and -Os, but it was not
added at part of https://github.com/KhronosGroup/SPIRV-Tools/pull/905.
This change will add that a well as some minor formatting changes
requested in that same pull request.
The previous algorithm would leave invalid code in the case of unreachable
blocks pointing into a dead branch. It would leave the unreachable blocks
branching to labels that no longer exist. The previous algorithm also left
unreachable blocks in some cases (a loop following an orphaned merge block).
This fix also addresses that.
This code will soon be replaced with the coming CFG cleanup.
There does not seem to be any pass that remove global variables. I
think we could use one. This pass will look specifically for global
variables that are not referenced and are not exported. Any decoration
associated with the variable will also be removed. However, this could
cause types or constants to become unreferenced. They will not be
removed. Another pass will have to be called to remove those.
The pass checks correctness of operands of instruction in opcode range
OpConvertFToU - OpBitset.
Disabled invalid tests
Disabled UConvert validation until Vulkan CTS can catch up.
Add validate_conversion to Android.mk
Also remove duplicate entry in CMakeLists.txt.
This is the first step in replacing the std::vector of Instruction
pointers to using and intrusive linked list.
To this end, we created the InstructionList class. It inherites from
the IntrusiveList class, but add the extra concept of ownership. An
InstructionList owns the instruction that are in it. This is to be
consistent with the current ownership rules where the vector owns the
instruction that are in it.
The other larger change is that the inst_ member of the BasicBlock class
was changed to using the InstructionList class.
Added test for the InsertBefore functions, and making sure that the
InstructionList destructor will delete the elements that it contains.
I've also add extra comments to explain ownership a little better.
- Adds a new pass CFGCleanupPass. This serves as an umbrella pass to
remove unnecessary cruft from a CFG.
- Currently, the only cleanup operation done is the removal of
unreachable basic blocks.
- Adds unit tests.
- Adds a flag to spirvopt to execute the pass (--cfg-cleanup).
There are no functional changes in this patch. The generic folding
routines in FoldSpecConstantOpAndCompositePass are now inside opt/fold.{cpp,h}.
This code will be used by the upcoming constant propagation pass. In
time, we'll add more expression folding and simplification into these
two files.
- switched from C to C++
- moved MARK-V model creation from backend to frontend
- The same MARK-V model object can be used to encode/decode multiple
files
- Added MARK-V model factory (currently only one option)
- Added --validate option to spirv-markv (run validation while
encoding/decoding)
This commit is the initial implementation of the intrusive linked list
class. It includes the implementation in the header files, and unit
test.
The iterators are circular: incrementing end() gives begin() and
decrementing begin() gives end(). Also made it valid to
decrement end().
Expliticly defines move constructor and move assignment
- Visual Studio 2013 does not implicitly generate the move constructor or
move assignments. So they need to be explicit, otherwise it will try to
use the copy constructor, which we explicitly deleted.
- Can't use "= default" either.
Seems like VS2013 does not support explicitly using the default move
constructors and move assignments, so I wrote them out.
Expands dead branch elimination to eliminate dead switch cases. It also
changes dbe to eliminate orphaned merge blocks and recursively eliminate
any blocks thereby orphaned.
These flags are expanded to a series of spirv-opt flags with the
following semantics:
-O: expands to passes that attempt to improve the performance of the
generated code.
-Os: expands to passes that attempt to reduce the size of the generated
code.
-Oconfig=<file> expands to the sequence of passes determined by the
flags specified in the user-provided file.
Add extra iterators for ir::Module's sections
Add extra getters to ir::Function
Add a const version of BasicBlock::GetLabelInst()
Use the max of all inputs' version as version
Split debug in debug1 and debug2
- Debug1 instructions have to be placed before debug2 instructions.
Error out if different addressing or memory models are found
Exit early if no binaries were given
Error out if entry points are redeclared
Implement copy ctors for Function and BasicBlock
- Visual Studio ends up generating copy constructors that call deleted
functions while compiling the linker code, while GCC and clang do not.
So explicitly write those functions to avoid Visual Studio messing up.
Move removing duplicate capabilities to its own pass
Add functions running on all IDs present in an instruction
Remove duplicate SpvOpExtInstImport
Give default options value for link functions
Remove linkage capability if not making a library
Check types before allowing to link
Detect if two types/variables/functions have different decorations
Remove decorations of imported variables/functions and their types
Add a DecorationManager
Add a method for removing all decorations of id
Add methods for removing operands from instructions
Error out if one of the modules has a non-zero schema
Update README.md to talk about the linker
Do not freak out if an imported built-in variable has no export
This keeps the previous behavior for other compilers that will
throw warnings on a negative shift operation, but works around
the internal compiler error in GCC.
Creates a pass called eliminate dead functions that looks for functions
that could never be called, and deletes them from the module.
To support this change a new function was added to the Pass class to
traverse the call trees from diffent starting points.
Includes a test to ensure that annotations are removed when deleting a
dead function. They were not, so fixed that up as well.
Did some cleanup of the assembly for the test in pass_test.cpp. Trying
to make them smaller and easier to read.
MARK-V codec was previously dependent on the validation state.
Now it doesn't need the validator to function, but can still optionally
create it and validate every instruction once it's decoded.
Previously we have several grammar tables defined as global static
variables and these grammar table entries contains non-POD struct
fields (CapabilitySet/ExtensionSet). The initialization of these
non-POD struct fields may require calling operator new. If used
as a library and the caller defines its own operator new, things
can screw up.
This pull request changes all global static variables into
function static variables, which is lazy evaluated in a thread
safe way as guaranteed by C++11.
- now includes a table of all descriptors with coding scheme
(improves performance by 5% by allowing to avoid creation of
move-to-front sequences which will never be used)
- increased the size of markv_autogen.inc, clang doesn't seem
to have the long compilation time problem now
(probably was inadvertently fixed by using Huffman codec
serialization)
Create a new optimization pass, strength reduction, which will replace
integer multiplication by a constant power of 2 with an equivalent bit
shift. More changes could be added later.
- Does not duplicate constants
- Adds vector |Concat| utility function to a common test header.
This optimizes a single index extract whose composite value terminates with a
CompositeConstruct (or ConstantComposite) by evaluating to the correct
component. This was needed for opaque legalization.
This highlights the need/opportunity to improve this optimization to deal
with more complex composite expressions including currently handled ops
plus Null ops and special vector composition. A TODO has been added.
Includes:
- Multi-sequence move-to-front
- Coding by id descriptor
- Statistical coding of non-id words
- Joint coding of opcode and num_operands
Removed explicit form Huffman codec constructor
- The standard use case for it is to be constructed from initializer list.
Using serialization for Huffman codecs
This adapts the fix for the single-block loop. Split the loop like
before. But when we move the OpLoopMerge back to the loop header,
redirect the continue target only when the original loop was a single
block loop.
Fixes https://github.com/KhronosGroup/SPIRV-Tools/issues/800
If the caller block is a single-block loop and inlining will
replace the caller block by several blocks, then:
- The original OpLoopMerge instruction will end up in the *last*
such block. That's the wrong place to put it.
- Move it back to the end of the first block.
- Update its Continue Target ID to point to the last block
We also have to take care of cases where the inlined code
begins with a structured header block. In this case
we need to ensure the restored OpLoopMerge does not appear
in the same block as the merge instruction from the callee's
first block.
Fixes https://github.com/KhronosGroup/SPIRV-Tools/issues/787
- DeadBranchElim: Make sure to mark orphan'd merge blocks and continue
targets as live.
- Add test with loop in dead branch
- Add test that orphan'd merge block is handled.
Fixes https://github.com/KhronosGroup/SPIRV-Tools/issues/776
Bit stream writer was manifesting incorrect behaviour when the following
two conditions were met:
- writer was on 64-bit word boundary
- WriteBits was invoked with num_bits=0 (can happen when a Huffman codec has only one
value)
The bug was causing very rare sporadic corruption which was detected by
tests after a random experimental change in MARK-V model.
Only inline calls to functions with opaque params or return
TODO: Handle parameter type or return type where the opqaue
type is buried within an array.
Includes code to deal correctly with OpFunctionParameter. This
is needed by opaque propagation which may not exhaustively inline
entry point functions.
Adds ProcessEntryPointCallTree: a method to do work on the
functions in the entry point call trees in a deterministic order.
Refactored the Huffman codec implementation and added ability to
serialize to C++-like text format. This would reduce the time-complexity
if loading hard-coded codecs.
Id descriptors are computed as a recursive hash of all instructions used
to define an id. Descriptors are invarint of actual id values and
the similar code in different files would produce the same descriptors.
Multiple ids can have the same descriptor. For example
%1 = OpConstant %u32 1
%2 = OpConstant %u32 1
would produce two ids with the same descriptor. But
%3 = OpConstant %s32 1
%4 = OpConstant %u32 2
would have descriptors different from %1 and %2.
Descriptors will be used as handles of move-to-front sequences in SPIR-V
compression.
ADCE will now generate correct code in the presence of function calls.
This is needed for opaque type optimization needed by glslang. Currently
all function calls are marked as live. TODO: mark calls live only if they
write a non-local.
This avoids conversion on variables which will not ultimately be optimized.
Also removed an obsolete restriction from FindTargetVars(). Also added
decorates to supported refs (eg. RelaxedPrecision). Also fixed name to
IsNonTypeDecorate().
- UniformElim: Only process reachable blocks
- UniformElim: Don't reuse loads of samplers and images across blocks.
Added a second phase which only reuses loads within a block for samplers
and images.
- UniformElim: Upgrade CopyObject skipping in GetPtr
- UniformElim: Add extensions whitelist
Currently disallowing SPV_KHR_variable_pointers because it doesn't
handle extended pointer forms.
- UniformElim: Do not process shaders with GroupDecorate
- UniformElim: Bail on shaders with non-32-bit ints.
- UniformElim: Document support for only single index and add TODO.
Add MultiMoveToFront class which supports multiple move-to-front
sequences and allows to promote value in all sequences at once.
Added caching for last accessed sequence handle and last accessed value
in each sequence.
Currently only SPV_KHR_variable_pointers is disallowed in passes which
do pointer analysis. Positive and negative tests of the general extensions
mechanism were added to aggressive_dce but cover all passes.
Visual Studio was complaining about possible loss of data on 64-bit
builds, due to an implicit cast from size_t to int. This changes the
data to use an int with no cast.
And always patch the backedge operand when patching phi functions. This
approach is more correct and cleaner. The previous code was generating
incorrect phis when the backedge block had no predecessors.
Create aggressive dead code elimination pass
This pass eliminates unused code from functions. In addition,
it detects and eliminates code which may have spurious uses but which do
not contribute to the output of the function. The most common cause of
such code sequences is summations in loops whose result is no longer used
due to dead code elimination. This optimization has additional compile
time cost over standard dead code elimination.
This pass only processes entry point functions. It also only processes
shaders with logical addressing. It currently will not process functions
with function calls. It currently only supports the GLSL.std.450 extended
instruction set. It currently does not support any extensions.
This pass will be made more effective by first running passes that remove
dead control flow and inlines function calls.
This pass can be especially useful after running Local Access Chain
Conversion, which tends to cause cycles of dead code to be left after
Store/Load elimination passes are completed. These cycles cannot be
eliminated with standard dead code elimination.
Additionally: This transform uses a whitelist of instructions that it
knows do have side effects, (a.k.a. combinators). It assumes other
instructions have side effects: it will not remove them, and assumes
they have side effects via their ID operands.
A SSA local variable load/store elimination pass.
For every entry point function, eliminate all loads and stores of function
scope variables only referenced with non-access-chain loads and stores.
Eliminate the variables as well.
The presence of access chain references and function calls can inhibit
the above optimization.
Only shader modules with logical addressing are currently processed.
Currently modules with any extensions enabled are not processed. This
is left for future work.
This pass is most effective if preceeded by Inlining and
LocalAccessChainConvert. LocalSingleStoreElim and LocalSingleBlockElim
will reduce the work that this pass has to do.
Fixes Instruction::ForEachInId so it covers
SPV_OPERAND_TYPE_MEMORY_SEMANTICS_ID and SPV_OPERAND_TYPE_SCOPE_ID.
Future proof a bit by using the common spvIsIdType routine.
Fixes https://github.com/KhronosGroup/SPIRV-Tools/issues/697
If this is used as a static library in another project, this does not
need to be installed, and otherwise will just clutter the application's install.
To use, define SKIP_SPIRV_TOOLS_INSTALL which internally defines
ENABLE_SPIRV_TOOLS_INSTALL to control installation.
Also include GNUInstallDirs to get standard output 'lib' directory which is sometimes 'lib64' and not 'lib'
Fixed width encoding is intended to be used for small unsigned integers
when the upper bound is known both to the encoder and the decoder
(for example move-to-front rank).
Command line application is located at tools/spirv-markv
API at include/spirv-tools/markv.h
At the moment only very basic compression is implemented, mostly varint.
Scope of supported SPIR-V opcodes is also limited.
Using a simple move-to-front implementation instead of encoding mapped
ids.
Work in progress:
- Does not cover all of SPIR-V
- Does not promise compatibility of compression/decompression across
different versions of the code.
The implementation is based on AVL and order statistic tree.
It accepts all kinds of values and the implementation
doesn't expect the behaviour to be consistent with id coding.
Intended by SPIR-V compression algorithms.
