From 063cbeaaea2fb00a10c6058ea4a9632092772ea5 Mon Sep 17 00:00:00 2001 From: ArielG-NV <159081215+ArielG-NV@users.noreply.github.com> Date: Thu, 7 Aug 2025 00:22:22 -0700 Subject: Initial copy elision pass (#8042) Fixes #7574 Changes: * Add an initial (fairly simple) optimization pass which is able to eliminate redundant copies. * Our current existing optimizer passes remove redundant load/store very robustly, this pass will focus on other cases of copy elimination * Primary approach is to make all functions which are `in T` and `T` is trivial to copy into a `__constref T`. We then (depending on scenario) manually insert a variable+load if a pass-by-reference is not possible; otherwise we pass by `constref`. * Added optimizations to eliminate redundant code which causes `constref` to fail to compile --------- Co-authored-by: Harsh Aggarwal Co-authored-by: Claude Co-authored-by: slangbot Co-authored-by: slangbot <186143334+slangbot@users.noreply.github.com> --- source/slang/slang-emit.cpp | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'source/slang/slang-emit.cpp') diff --git a/source/slang/slang-emit.cpp b/source/slang/slang-emit.cpp index 405bca5a2..7d8f1438d 100644 --- a/source/slang/slang-emit.cpp +++ b/source/slang/slang-emit.cpp @@ -110,6 +110,7 @@ #include "slang-ir-strip-default-construct.h" #include "slang-ir-strip-legalization-insts.h" #include "slang-ir-synthesize-active-mask.h" +#include "slang-ir-transform-params-to-constref.h" #include "slang-ir-translate-global-varying-var.h" #include "slang-ir-undo-param-copy.h" #include "slang-ir-uniformity.h" @@ -1714,6 +1715,12 @@ Result linkAndOptimizeIR( // For CUDA/OptiX like targets, add our pass to replace inout parameter copies with direct // pointers undoParameterCopy(irModule); + // Transform struct parameters to use ConstRef for better performance + if (isCPUTarget(targetRequest) || isCUDATarget(targetRequest) || + isMetalTarget(targetRequest)) + { + transformParamsToConstRef(irModule, codeGenContext->getSink()); + } #if 0 dumpIRIfEnabled(codeGenContext, irModule, "PARAMETER COPIES REPLACED WITH DIRECT POINTERS"); #endif -- cgit v1.2.3