diff options
Diffstat (limited to 'source/slang')
| -rw-r--r-- | source/slang/slang-ir-eliminate-multilevel-break.cpp | 10 | ||||
| -rw-r--r-- | source/slang/slang-ir-simplify-cfg.cpp | 23 |
2 files changed, 31 insertions, 2 deletions
diff --git a/source/slang/slang-ir-eliminate-multilevel-break.cpp b/source/slang/slang-ir-eliminate-multilevel-break.cpp index 7db517309..8f7307f1b 100644 --- a/source/slang/slang-ir-eliminate-multilevel-break.cpp +++ b/source/slang/slang-ir-eliminate-multilevel-break.cpp @@ -59,6 +59,11 @@ struct EliminateMultiLevelBreakContext HashSet<IRBlock*> processedBlocks; List<MultiLevelBreakInfo> multiLevelBreaks; + bool isUnreachable(IRBlock* block) + { + return block->getPredecessors().getCount() == 0; + } + void collectBreakableRegionBlocks(BreakableRegionInfo& info) { // Push break block to a stack so we can easily check if a block is a break block in its @@ -92,7 +97,7 @@ struct EliminateMultiLevelBreakContext collectBreakableRegionBlocks(*childRegion); info.childRegions.add(childRegion); block = childRegion->getBreakBlock(); - if (info.blockSet.add(block)) + if (!isUnreachable(block) && info.blockSet.add(block)) { info.blocks.add(block); } @@ -142,7 +147,8 @@ struct EliminateMultiLevelBreakContext l->forEach( [&](BreakableRegionInfo* region) { - mapBreakBlockToRegion.add(region->getBreakBlock(), region); + if(!isUnreachable(region->getBreakBlock())) + mapBreakBlockToRegion.add(region->getBreakBlock(), region); for (auto block : region->blocks) mapBlockToRegion.add(block, region); }); diff --git a/source/slang/slang-ir-simplify-cfg.cpp b/source/slang/slang-ir-simplify-cfg.cpp index c4c5b584e..f2d0c4555 100644 --- a/source/slang/slang-ir-simplify-cfg.cpp +++ b/source/slang/slang-ir-simplify-cfg.cpp @@ -94,6 +94,29 @@ static bool isTrivialSingleIterationLoop( } } } + + // We'll also check if there's an inner loop that is breaking out into this loop's break block. + // If so, we cannot remove it right away since it interferes with the multi-level break elimination + // logic. + // + // Track the break block backwards through the dominator tree, and see if we find a loop block + // that is not the current loop. + // + auto currBlock = loop->getBreakBlock(); + for (;;) + { + auto parent = context.domTree->getImmediateDominator(currBlock); + if (!parent) + break; + currBlock = parent; + if (auto _loop = as<IRLoop>(currBlock->getTerminator())) + { + if (loop != _loop) + return false; + if (loop == _loop) + break; + } + } return true; } |