diff options
| -rw-r--r-- | lib/CodeGen/MachineBlockPlacement.cpp | 6 | ||||
| -rw-r--r-- | test/CodeGen/X86/block-placement.ll | 56 |
2 files changed, 59 insertions, 3 deletions
diff --git a/lib/CodeGen/MachineBlockPlacement.cpp b/lib/CodeGen/MachineBlockPlacement.cpp index 45d5af2..870e248 100644 --- a/lib/CodeGen/MachineBlockPlacement.cpp +++ b/lib/CodeGen/MachineBlockPlacement.cpp @@ -315,7 +315,7 @@ void MachineBlockPlacement::markChainSuccessors( // This is a cross-chain edge that is within the loop, so decrement the // loop predecessor count of the destination chain. if (SuccChain.LoopPredecessors > 0 && --SuccChain.LoopPredecessors == 0) - BlockWorkList.push_back(*SI); + BlockWorkList.push_back(*SuccChain.begin()); } } } @@ -594,7 +594,7 @@ void MachineBlockPlacement::buildLoopChains(MachineFunction &F, } if (Chain.LoopPredecessors == 0) - BlockWorkList.push_back(*BI); + BlockWorkList.push_back(*Chain.begin()); } buildChain(*L.block_begin(), LoopChain, BlockWorkList, &LoopBlockSet); @@ -692,7 +692,7 @@ void MachineBlockPlacement::buildCFGChains(MachineFunction &F) { } if (Chain.LoopPredecessors == 0) - BlockWorkList.push_back(BB); + BlockWorkList.push_back(*Chain.begin()); } BlockChain &FunctionChain = *BlockToChain[&F.front()]; diff --git a/test/CodeGen/X86/block-placement.ll b/test/CodeGen/X86/block-placement.ll index 891db5a..a6ddc4d 100644 --- a/test/CodeGen/X86/block-placement.ll +++ b/test/CodeGen/X86/block-placement.ll @@ -593,3 +593,59 @@ exit: ret void } +define void @unanalyzable_branch_to_best_succ(i1 %cond) { +; Ensure that we can handle unanalyzable branches where the destination block +; gets selected as the optimal sucessor to merge. +; +; CHECK: unanalyzable_branch_to_best_succ +; CHECK: %entry +; CHECK: %foo +; CHECK: %bar +; CHECK: %exit + +entry: + ; Bias this branch toward bar to ensure we form that chain. + br i1 %cond, label %bar, label %foo, !prof !1 + +foo: + %cmp = fcmp une double 0.000000e+00, undef + br i1 %cmp, label %bar, label %exit + +bar: + call i32 @f() + br label %exit + +exit: + ret void +} + +define void @unanalyzable_branch_to_free_block(float %x) { +; Ensure that we can handle unanalyzable branches where the destination block +; gets selected as the best free block in the CFG. +; +; CHECK: unanalyzable_branch_to_free_block +; CHECK: %entry +; CHECK: %a +; CHECK: %b +; CHECK: %c +; CHECK: %exit + +entry: + br i1 undef, label %a, label %b + +a: + call i32 @f() + br label %c + +b: + %cmp = fcmp une float %x, undef + br i1 %cmp, label %c, label %exit + +c: + call i32 @g() + br label %exit + +exit: + ret void +} + |