diff options
| author | FICTURE7 <FICTURE7@gmail.com> | 2020-09-12 19:32:53 +0400 |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2020-09-12 12:32:53 -0300 |
| commit | 36ec1bc6c023811235d9f5fb664feff09bc7b4f7 (patch) | |
| tree | 98d74ad92cdce8294bb5116bf7cd06acb55ff9da /ARMeilleure/Translation/EmitterContext.cs | |
| parent | 3d055da5fc77f462e9c7099e08570213c0220cd4 (diff) | |
Relax block ordering constraints (#1535)
* Relax block ordering constraints
Before `block.Next` had to follow `block.ListNext`, now it does not.
Instead `CodeGenerator` will now emit the necessary jump instructions
to ensure control flow.
This makes control flow and block order modifications easier. It also
eliminates some simple cases of redundant branches.
* Set PPTC version
Diffstat (limited to 'ARMeilleure/Translation/EmitterContext.cs')
| -rw-r--r-- | ARMeilleure/Translation/EmitterContext.cs | 44 |
1 files changed, 27 insertions, 17 deletions
diff --git a/ARMeilleure/Translation/EmitterContext.cs b/ARMeilleure/Translation/EmitterContext.cs index a6cc55df..2261fb87 100644 --- a/ARMeilleure/Translation/EmitterContext.cs +++ b/ARMeilleure/Translation/EmitterContext.cs @@ -13,18 +13,17 @@ namespace ARMeilleure.Translation class EmitterContext { - private Dictionary<Operand, BasicBlock> _irLabels; - - private IntrusiveList<BasicBlock> _irBlocks; + private readonly Dictionary<Operand, BasicBlock> _irLabels; + private readonly IntrusiveList<BasicBlock> _irBlocks; private BasicBlock _irBlock; + private BasicBlock _ifBlock; private bool _needsNewBlock; public EmitterContext() { _irLabels = new Dictionary<Operand, BasicBlock>(); - _irBlocks = new IntrusiveList<BasicBlock>(); _needsNewBlock = true; @@ -57,16 +56,16 @@ namespace ARMeilleure.Translation public void Branch(Operand label) { - Add(Instruction.Branch, null); + NewNextBlockIfNeeded(); - BranchToLabel(label); + BranchToLabel(label, uncond: true); } public void BranchIf(Operand label, Operand op1, Operand op2, Comparison comp) { Add(Instruction.BranchIf, null, op1, op2, Const((int)comp)); - BranchToLabel(label); + BranchToLabel(label, uncond: false); } public void BranchIfFalse(Operand label, Operand op1) @@ -574,10 +573,7 @@ namespace ARMeilleure.Translation private Operand Add(Intrinsic intrin, Operand dest, params Operand[] sources) { - if (_needsNewBlock) - { - NewNextBlock(); - } + NewNextBlockIfNeeded(); IntrinsicOperation operation = new IntrinsicOperation(intrin, dest, sources); @@ -586,7 +582,7 @@ namespace ARMeilleure.Translation return dest; } - private void BranchToLabel(Operand label) + private void BranchToLabel(Operand label, bool uncond) { if (!_irLabels.TryGetValue(label, out BasicBlock branchBlock)) { @@ -595,7 +591,15 @@ namespace ARMeilleure.Translation _irLabels.Add(label, branchBlock); } - _irBlock.Branch = branchBlock; + if (uncond) + { + _irBlock.AddSuccessor(branchBlock); + } + else + { + // Defer registration of successor to _irBlock so that the order of successors is correct. + _ifBlock = branchBlock; + } _needsNewBlock = true; } @@ -629,9 +633,16 @@ namespace ARMeilleure.Translation private void NextBlock(BasicBlock nextBlock) { - if (_irBlock != null && !EndsWithUnconditional(_irBlock)) + if (_irBlock != null && _irBlock.SuccessorCount == 0 && !EndsWithUnconditional(_irBlock)) { - _irBlock.Next = nextBlock; + _irBlock.AddSuccessor(nextBlock); + + if (_ifBlock != null) + { + _irBlock.AddSuccessor(_ifBlock); + + _ifBlock = null; + } } _irBlock = nextBlock; @@ -642,8 +653,7 @@ namespace ARMeilleure.Translation private static bool EndsWithUnconditional(BasicBlock block) { return block.Operations.Last is Operation lastOp && - (lastOp.Instruction == Instruction.Branch || - lastOp.Instruction == Instruction.Return || + (lastOp.Instruction == Instruction.Return || lastOp.Instruction == Instruction.Tailcall); } |