diff options
Diffstat (limited to 'source/slang')
| -rw-r--r-- | source/slang/slang-emit-c-like.cpp | 9 | ||||
| -rw-r--r-- | source/slang/slang-ir-lower-generic-var.cpp | 8 | ||||
| -rw-r--r-- | source/slang/slang-ir-lower-generics.cpp | 9 | ||||
| -rw-r--r-- | source/slang/slang-ir.cpp | 1 |
4 files changed, 26 insertions, 1 deletions
diff --git a/source/slang/slang-emit-c-like.cpp b/source/slang/slang-emit-c-like.cpp index 733811183..a3b11a908 100644 --- a/source/slang/slang-emit-c-like.cpp +++ b/source/slang/slang-emit-c-like.cpp @@ -1074,6 +1074,15 @@ bool CLikeSourceEmitter::shouldFoldInstIntoUseSites(IRInst* inst) if(inst->findDecoration<IRPreciseDecoration>()) return false; + // In general, undefined value should be emitted as an uninitialized + // variable, so we shouldn't fold it. + // However, we cannot emit all undefined values a separate variable + // definition for certain types on certain targets (e.g. `out TriangleStream<T>` + // for GLSL), so we check this only after all those special cases are + // considered. + if (inst->op == kIROp_undefined) + return false; + // Okay, at this point we know our instruction must have a single use. auto use = inst->firstUse; SLANG_ASSERT(use); diff --git a/source/slang/slang-ir-lower-generic-var.cpp b/source/slang/slang-ir-lower-generic-var.cpp index 8799dea6b..936ed017f 100644 --- a/source/slang/slang-ir-lower-generic-var.cpp +++ b/source/slang/slang-ir-lower-generic-var.cpp @@ -79,6 +79,12 @@ namespace Slang // have already been replaced with the pointer to that variable by now. // So we don't need to do anything here. } + else if (valPtr->op == kIROp_undefined) + { + // We don't need to store an undef value. + storeInst->removeAndDeallocate(); + return; + } else { // If value does not come from another generic variable, then it must be @@ -138,7 +144,7 @@ namespace Slang void processInst(IRInst* inst) { - if (inst->op == kIROp_Var || inst->op == kIROp_undefined) + if (inst->op == kIROp_Var) { processVarInst(inst); } diff --git a/source/slang/slang-ir-lower-generics.cpp b/source/slang/slang-ir-lower-generics.cpp index 61fa8ad17..c60b5386a 100644 --- a/source/slang/slang-ir-lower-generics.cpp +++ b/source/slang/slang-ir-lower-generics.cpp @@ -6,6 +6,8 @@ #include "slang-ir-lower-generic-call.h" #include "slang-ir-lower-generic-var.h" #include "slang-ir-witness-table-wrapper.h" +#include "slang-ir-ssa.h" +#include "slang-ir-dce.h" namespace Slang { @@ -16,7 +18,14 @@ namespace Slang sharedContext.module = module; lowerGenericFunctions(&sharedContext); lowerGenericCalls(&sharedContext); + // We might have generated new temporary variables during lowering. + // An SSA pass can clean up unncessary load/stores. + constructSSA(module); + eliminateDeadCode(module); lowerGenericVar(&sharedContext); + // After lowerGenericVar, there could be some unused `undef` values. + // We eliminate them in a DCE pass. + eliminateDeadCode(module); generateWitnessTableWrapperFunctions(&sharedContext); } } // namespace Slang diff --git a/source/slang/slang-ir.cpp b/source/slang/slang-ir.cpp index fc4b71138..f551dcbba 100644 --- a/source/slang/slang-ir.cpp +++ b/source/slang/slang-ir.cpp @@ -5151,6 +5151,7 @@ namespace Slang return false; case kIROp_Nop: + case kIROp_undefined: case kIROp_Specialize: case kIROp_lookup_interface_method: case kIROp_getAddr: |