* AddToWorklist can now be called unconditionally
* It will only add instructions that have not already been marked as
live
* Fixes a case where a merge was not added to the worklist because the
branch was already marked as live
* Added two similar tests that fail without the fix
Modified ADCE to remove dead globals.
* Entry point and execution mode instructions are marked as alive
* Reachable functions and their parameters are marked as alive
* Instruction deletion now deferred until the end of the pass
* Eliminated dead insts set, added IsDead to calculate that value
instead
* Ported applicable dead variable elimination tests
* Ported dead constant elim tests
Added dead function elimination to ADCE
* ported dead function elim tests
Added handling of decoration groups in ADCE
* Uses a custom sorter to traverse decorations in a specific order
* Simplifies necessary checks
Updated -O and -Os pass lists.
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.
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
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.
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.
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.
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.
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.
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.