These are bookend passes designed to help preserve line information
across passes which delete, move and clone instructions. The propagation
pass attaches a debug line instruction to every instruction based on
SPIR-V line propagation rules. It should be performed before optimization.
The redundant line elimination pass eliminates all line instructions
which match the previous line instruction. This pass should be performed
at the end of optimization to reduce physical SPIR-V file size.
Fixes#2027.
* Add base and core bindless validation instrumentation classes
* Fix formatting.
* Few more formatting fixes
* Fix build failure
* More build fixes
* Need to call non-const functions in order.
Specifically, these are functions which call TakeNextId(). These need to
be called in a specific order to guarantee that tests which do exact
compares will work across all platforms. c++ pretty much does not
guarantee order of evaluation of operands, so any such functions need to
be called separately in individual statements to guarantee order.
* More ordering.
* And more ordering.
* And more formatting.
* Attempt to fix NDK build
* Another attempt to address NDK build problem.
* One more attempt at NDK build failure
* Add instrument.hpp to BUILD.gn
* Some name improvement in instrument.hpp
* Change all types in instrument.hpp to int.
* Improve documentation in instrument.hpp
* Format fixes
* Comment clean up in instrument.hpp
* imageInst -> image_inst
* Fix GetLabel() issue.
* Create structed cfg analysis.
There are lots of optimization that have to traverse the CFG in a
structured order just because it wants to know which constructs a
basic block in contained in. This adds extra complexity to these
optimizations, for causes too much refactoring of older optimizations.
To help with this problem, I have written an analysis that can give this
information.
* Identify branches breaking from loops.
Dead branch elimination does a search for a conditional branch to the
end of the current selection construct. This search assumes that the
only way to leave the construct is through the merge node. But that is
not true. The code can jump to the merge node of a loop that contains
the construct.
The search needs to take this into consideration.
* Create a new entry point for the optimizer
Creates a new struct to hold the options for the optimizer, and creates
an entry point that take the optimizer options as a parameter.
The old entry point that takes validator options are now deprecated.
The validator options will be one of the optimizer options.
Part of the optimizer options will also be the upper bound on the id bound.
* Add a command line option to set the max value for the id bound. The default is 0x3FFFFF.
* Modify `TakeNextIdBound` to return 0 when the limit is reached.
* Split constant opcode validation out of idUsage and into
validate_constants.cpp
* minor style fixes
* reduced duplication
* fixed an issue with array sizing
* Moved function opcode validation out of idUsage and into new files
* minor style changes
* General opcode checking is in validate_function.cpp
* Execution limitation checking is in
validate_execution_limitations.cpp
* Execution limitations was split into a new pass as it requires other
validation to register those limitations first.
* Moved type instruction validation out of validation idUsage into a new
file
* Consolidate type unique pass into new file
* Removed one bad test
* Reworked validation ordering
* Refactored the Memory class of instructions in the spec out Id
validation and into a new pass
* Tests unmodified
* some minor disassembly changes
* minor style changes
* Combines OpAccessChain, OpInBoundsAccessChain, OpPtrAccessChain and
OpInBoundsPtrAccessChain
* New folding rule to fold add with 0 for integers
* Converts to a bitcast if the result type does not match the operand
type
V
This CL moves the various validate files into the val/ directory with
the rest of the validation infrastructure. This matches how opt/ is
setup with the passes with the infrastructure.
Fixes#1120
Checks that all static uses of the Input and Output variables are listed
as interfaces in each corresponding entry point declaration.
* Changed validation state to track interface lists
* updated many tests
* Modified validation state to store entry point names
* Combined with interface list and called EntryPointDescription
* Updated uses
* Changed interface validation error messages to output entry point name
in addtion to ID
We have already disabled common uniform elimination because it created
sequences of loads an entire uniform object, then we extract just a
single element. This caused problems in some drivers, and is just
generally slow because it loads more memory than needed.
However, there are other way to get into this situation, so I've added
a pass that looks specifically for this pattern and removes it when only
a portion of the load is used.
Fixes#1547.
This pass will look for adjacent loops that are compatible and legal to
be fused.
Loops are compatible if:
- they both have one induction variable
- they have the same upper and lower bounds
- same initial value
- same condition
- they have the same update step
- they are adjacent
- there are no break/continue in either of them
Fusion is legal if:
- fused loops do not have any dependencies with dependence distance
greater than 0 that did not exist in the original loops.
- there are no function calls in the loops (could have side-effects)
- there are no barriers in the loops
It will fuse all such loops as long as the number of registers used for
the fused loop stays under the threshold defined by
max_registers_per_loop.
Adds support for spliting loops whose register pressure exceeds a user
provided level. This pass will split a loop into two or more loops given
that the loop is a top level loop and that spliting the loop is legal.
Control flow is left intact for dead code elimination to remove.
This pass is enabled with the --loop-fission flag to spirv-opt.
Introduce a pass that does a DCE type analysis for vector elements
instead of the whole vector as a single element.
It will then rewrite instructions that are not used with something else.
For example, an instruction whose value are not used, even though it is
referenced, is replaced with an OpUndef.
For each function, the analysis determine which SSA registers are live
at the beginning of each basic block and which one are killed at
the end of the basic block.
It also includes utilities to simulate the register pressure for loop
fusion and fission.
The implementation is based on the paper "A non-iterative data-flow
algorithm for computing liveness sets in strict ssa programs" from
Boissinot et al.
* Adds new pass for validating non-uniform group instructions
* Currently on checks execution scope for Vulkan 1.1 and SPIR-V 1.3
* Added test framework
Provides functionality to perform ZIV and SIV dependency analysis tests
between a load and store within the same loop.
Dependency tests rely on scalar analysis to prove and disprove dependencies
with regard to the loop being analysed.
Based on the 1990 paper Practical Dependence Testing by Goff, Kennedy, Tseng
Adds support for marking loops in the loop nest as IRRELEVANT.
Loops are marked IRRELEVANT if the analysed instructions contain
no induction variables for the loops, i.e. the loops induction
variable is not relevent to the dependence of the store and load.
This patch adds support for the analysis of scalars in loops. It works
by traversing the defuse chain to build a DAG of scalar operations and
then simplifies the DAG by folding constants and grouping like terms.
It represents induction variables as recurrent expressions with respect
to a given loop and can simplify DAGs containing recurrent expression by
rewritting the entire DAG to be a recurrent expression with respect to
the same loop.
The sprir-v generated from HLSL code contain many copyies of very large
arrays. Not only are these time consumming, but they also cause
problems for drivers because they require too much space.
To work around this, we will implement an array copy propagation. Note
that we will not implement a complete array data flow analysis in order
to implement this. We will be looking for very simple cases:
1) The source must never be stored to.
2) The target must be stored to exactly once.
3) The store to the target must be a store to the entire array, and be a
copy of the entire source.
4) All loads of the target must be dominated by the store.
The hard part is keeping all of the types correct. We do not want to
have to do too large a search to update everything, which may not be
possible, do we give up if we see any instruction that might be hard to
update.
Also in types.h, the element decorations are not stored in an std::map.
This change was done so the hashing algorithm for a Struct is
consistent. With the std::unordered_map, the traversal order was
non-deterministic leading to the same type getting hashed to different
values. See |Struct::GetExtraHashWords|.
Contributes to #1416.
Added a framework for validation of BuiltIn variables. The framework
allows implementation of flexible abstract rules which are required for
built-ins as the information (decoration, definition, reference) is not
in one place, but is scattered all over the module.
Validation rules are implemented as a map
id -> list<functor(instrution)>
Ids which are dependent on built-in types or objects receive a task
list, such as "this id cannot be referenced from function which is
called from entry point with execution model X; propagate this rule
to your descendants in the global scope".
Also refactored test/val/val_fixtures.
All built-ins covered by tests
This patch adds a new option --time-report to spirv-opt. For each pass
executed by spirv-opt, the flag prints resource utilization for the pass
(CPU time, wall time, RSS and page faults)
This fixes issue #1378
This pass replaces the load/store elimination passes. It implements the
SSA re-writing algorithm proposed in
Simple and Efficient Construction of Static Single Assignment Form.
Braun M., Buchwald S., Hack S., Leißa R., Mallon C., Zwinkau A. (2013)
In: Jhala R., De Bosschere K. (eds)
Compiler Construction. CC 2013.
Lecture Notes in Computer Science, vol 7791.
Springer, Berlin, Heidelberg
https://link.springer.com/chapter/10.1007/978-3-642-37051-9_6
In contrast to common eager algorithms based on dominance and dominance
frontier information, this algorithm works backwards from load operations.
When a target variable is loaded, it queries the variable's reaching
definition. If the reaching definition is unknown at the current location,
it searches backwards in the CFG, inserting Phi instructions at join points
in the CFG along the way until it finds the desired store instruction.
The algorithm avoids repeated lookups using memoization.
For reducible CFGs, which are a superset of the structured CFGs in SPIRV,
this algorithm is proven to produce minimal SSA. That is, it inserts the
minimal number of Phi instructions required to ensure the SSA property, but
some Phi instructions may be dead
(https://en.wikipedia.org/wiki/Static_single_assignment_form).
The loop peeler util takes a loop as input and create a new one before.
The iterator of the duplicated loop then set to accommodate the number
of iteration required for the peeling.
The loop peeling pass that decided to do the peeling and profitability
analysis is left for a follow-up PR.
Strips reflection info. This is limited to decorations and
decoration instructions related to the SPV_GOOGLE_hlsl_functionality1
extension.
It will remove the OpExtension for SPV_GOOGLE_hlsl_functionality1.
It will also remove the OpExtension for SPV_GOOGLE_decorate_string
if there are no further remaining uses of OpDecorateStringGOOGLE.
Fixes https://github.com/KhronosGroup/SPIRV-Tools/issues/1398
The default target is SPIR-V 1.3.
For example, spirv-as will generate a SPIR-V 1.3 binary by default.
Use command line option "--target-env spv1.0" if you want to make a SPIR-V
1.0 binary or validate against SPIR-V 1.0 rules.
Example:
# Generate a SPIR-V 1.0 binary instead of SPIR-V 1.3
spirv-as --target-env spv1.0 a.spvasm -o a.spv
spirv-as --target-env vulkan1.0 a.spvasm -o a.spv
# Validate as SPIR-V 1.0.
spirv-val --target-env spv1.0 a.spv
# Validate as Vulkan 1.0
spirv-val --target-env vulkan1.0 a.spv
Some tokens are only showing up in the unified1 grammar.
So enum string mappings have to be generated from that grammar, not
the grammar from the (deprecated) include/spirv/1.2 grammar.
Example: capabilities FragmentFullyCovered, Float16ImageAMD
It moves all conditional branching and switch whose conditions are loop
invariant and uniform. Before performing the loop unswitch we check that
the loop does not contain any instruction that would prevent it
(barriers, group instructions etc.).
This patch adds initial support for loop unrolling in the form of a
series of utility classes which perform the unrolling. The pass can
be run with the command spirv-opt --loop-unroll. This will unroll
loops within the module which have the unroll hint set. The unroller
imposes a number of requirements on the loops it can unroll. These are
documented in the comments for the LoopUtils::CanPerformUnroll method in
loop_utils.h. Some of the restrictions will be lifted in future patches.
Implementation of the simplification pass.
- Create pass that calls the instruction folder on each instruction and
propagate instructions that fold to a copy. This will do copy
propagation as well.
- Did not use the propagator engine because I want to modify the instruction
as we go along.
- Change folding to not allocate new instructions, but make changes in
place. This change had a big impact on compile time.
- Add simplification pass to the legalization passes in place of
insert-extract elimination.
- Added test cases for new folding rules.
- Added tests for the simplification pass
- Added a method to the CFG to apply a function to the basic blocks in
reverse post order.
Contributes to #1164.
Create the folding engine that will
1) attempt to fold an instruction.
2) iterates on the folding so small folding rules can be easily combined.
3) insert new instructions when needed.
I've added the minimum number of rules needed to test the features above.
Creates a pass that will remove instructions that are invalid for the
current shader stage. For the instruction to be considered for replacement
1) The opcode must be valid for a shader modules.
2) The opcode must be invalid for the current shader stage.
3) All entry points to the module must be for the same shader stage.
4) The function containing the instruction must be reachable from an entry point.
Fixes#1247.
* Handles simple cases only
* Identifies phis in blocks with two predecessors and attempts to
convert the phi to an select
* does not perform code motion currently so the converted values must
dominate the join point (e.g. can't be defined in the branches)
* limited for now to two predecessors, but can be extended to handle
more cases
* Adding if conversion to -O and -Os
We have come across a driver bug where and OpUnreachable inside a loop
is causing the shader to go into an infinite loop. This commit will try
to avoid this bug by turning OpUnreachable instructions that are
contained in a loop into branches to the loop merge block.
This is not added to "-O" and "-Os" because it should only be used if
the driver being targeted has this problem.
Fixes#1209.
Add post-order tree iterator.
Add DominatorTreeNode extensions:
- Add begin/end methods to do pre-order and post-order tree traversal from a given DominatorTreeNode
Add DominatorTree extensions:
- Add begin/end methods to do pre-order and post-order tree traversal
- Tree traversal ignore by default the pseudo entry block
- Retrieve a DominatorTreeNode from a basic block
Add loop descriptor:
- Add a LoopDescriptor class to register all loops in a given function.
- Add a Loop class to describe a loop:
- Loop parent
- Nested loops
- Loop depth
- Loop header, merge, continue and preheader
- Basic blocks that belong to the loop
Correct a bug that forced dominator tree to be constantly rebuilt.
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.
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.
