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Restructure code to reduce ifcvt compile time cost.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37543 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evan Cheng
parent
f60e5a2cd9
commit
9618bcaf7d
@ -55,17 +55,13 @@ STATISTIC(NumIfConvBBs, "Number of if-converted blocks");
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namespace {
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class IfConverter : public MachineFunctionPass {
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enum BBICKind {
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ICNotAnalyzed, // BB has not been analyzed.
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ICReAnalyze, // BB must be re-analyzed.
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ICNotClassfied, // BB data valid, but not classified.
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ICSimple, // BB is entry of an one split, no rejoin sub-CFG.
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ICSimpleFalse, // Same as ICSimple, but on the false path.
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ICTriangle, // BB is entry of a triangle sub-CFG.
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ICTriangleFalse, // Same as ICTriangle, but on the false path.
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ICTriangleFRev, // Same as ICTriangleFalse, but false path rev condition.
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ICDiamond, // BB is entry of a diamond sub-CFG.
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ICChild, // BB is part of the sub-CFG that'll be predicated.
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ICDead // BB cannot be if-converted again.
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ICDiamond // BB is entry of a diamond sub-CFG.
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};
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/// BBInfo - One per MachineBasicBlock, this is used to cache the result
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@ -76,29 +72,41 @@ namespace {
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/// instruction can clobber the 'would-be' predicate.
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///
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/// Kind - Type of block. See BBICKind.
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/// NonPredSize - Number of non-predicated instructions.
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/// IsAnalyzable - True if AnalyzeBranch() returns false.
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/// ModifyPredicate - True if BB would modify the predicate (e.g. has
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/// IsDone - True if BB is not to be considered for ifcvt.
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/// IsBeingAnalyzed - True if BB is currently being analyzed.
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/// IsAnalyzed - True if BB has been analyzed (info is still valid).
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/// IsEnqueued - True if BB has been enqueued to be ifcvt'ed.
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/// IsBrAnalyzable - True if AnalyzeBranch() returns false.
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/// HasFallThrough - True if BB may fallthrough to the following BB.
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/// IsUnpredicable - True if BB is known to be unpredicable.
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/// ClobbersPredicate- True if BB would modify the predicate (e.g. has
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/// cmp, call, etc.)
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/// NonPredSize - Number of non-predicated instructions.
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/// BB - Corresponding MachineBasicBlock.
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/// TrueBB / FalseBB- See AnalyzeBranch().
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/// BrCond - Conditions for end of block conditional branches.
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/// Predicate - Predicate used in the BB.
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struct BBInfo {
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BBICKind Kind;
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bool IsDone : 1;
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bool IsBeingAnalyzed : 1;
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bool IsAnalyzed : 1;
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bool IsEnqueued : 1;
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bool IsBrAnalyzable : 1;
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bool HasFallThrough : 1;
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bool IsUnpredicable : 1;
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bool ClobbersPred : 1;
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unsigned NonPredSize;
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bool IsAnalyzable;
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bool HasFallThrough;
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bool ModifyPredicate;
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MachineBasicBlock *BB;
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MachineBasicBlock *TrueBB;
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MachineBasicBlock *FalseBB;
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MachineBasicBlock *TailBB;
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std::vector<MachineOperand> BrCond;
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std::vector<MachineOperand> Predicate;
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BBInfo() : Kind(ICNotAnalyzed), NonPredSize(0),
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IsAnalyzable(false), HasFallThrough(false),
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ModifyPredicate(false),
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BBInfo() : Kind(ICNotClassfied), IsDone(false), IsBeingAnalyzed(false),
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IsAnalyzed(false), IsEnqueued(false), IsBrAnalyzable(false),
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HasFallThrough(false), IsUnpredicable(false),
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ClobbersPred(false), NonPredSize(0),
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BB(0), TrueBB(0), FalseBB(0), TailBB(0) {}
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};
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@ -127,7 +135,7 @@ namespace {
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bool FalseBranch = false) const;
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bool ValidDiamond(BBInfo &TrueBBI, BBInfo &FalseBBI) const;
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void ScanInstructions(BBInfo &BBI);
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void AnalyzeBlock(MachineBasicBlock *BB);
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BBInfo &AnalyzeBlock(MachineBasicBlock *BB);
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bool FeasibilityAnalysis(BBInfo &BBI, std::vector<MachineOperand> &Cond,
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bool isTriangle = false, bool RevBranch = false);
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bool AttemptRestructuring(BBInfo &BBI);
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@ -145,7 +153,7 @@ namespace {
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// blockAlwaysFallThrough - Block ends without a terminator.
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bool blockAlwaysFallThrough(BBInfo &BBI) const {
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return BBI.IsAnalyzable && BBI.TrueBB == NULL;
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return BBI.IsBrAnalyzable && BBI.TrueBB == NULL;
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}
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// IfcvtCandidateCmp - Used to sort if-conversion candidates.
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@ -192,15 +200,15 @@ bool IfConverter::runOnMachineFunction(MachineFunction &MF) {
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BBInfo &BBI = *Candidates.back();
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Candidates.pop_back();
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// If the block has been evicted out of the queue or it has already been
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// marked dead (due to it being predicated), then skip it.
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if (!BBI.IsEnqueued || BBI.IsDone)
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continue;
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bool RetVal = false;
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switch (BBI.Kind) {
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default: assert(false && "Unexpected!");
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break;
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case ICReAnalyze:
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// One or more of 'children' have been modified, abort!
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case ICDead:
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// Block has been already been if-converted, abort!
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break;
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case ICSimple:
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case ICSimpleFalse: {
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bool isFalse = BBI.Kind == ICSimpleFalse;
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@ -304,6 +312,9 @@ static inline MachineBasicBlock *getNextBlock(MachineBasicBlock *BB) {
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/// ValidSimple - Returns true if the 'true' block (along with its
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/// predecessor) forms a valid simple shape for ifcvt.
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bool IfConverter::ValidSimple(BBInfo &TrueBBI) const {
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if (TrueBBI.IsBeingAnalyzed)
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return false;
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return !blockAlwaysFallThrough(TrueBBI) &&
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TrueBBI.BrCond.size() == 0 && TrueBBI.BB->pred_size() == 1;
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}
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@ -312,6 +323,9 @@ bool IfConverter::ValidSimple(BBInfo &TrueBBI) const {
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/// with their common predecessor) forms a valid triangle shape for ifcvt.
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bool IfConverter::ValidTriangle(BBInfo &TrueBBI, BBInfo &FalseBBI,
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bool FalseBranch) const {
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if (TrueBBI.IsBeingAnalyzed)
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return false;
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if (TrueBBI.BB->pred_size() != 1)
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return false;
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@ -328,6 +342,9 @@ bool IfConverter::ValidTriangle(BBInfo &TrueBBI, BBInfo &FalseBBI,
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/// ValidDiamond - Returns true if the 'true' and 'false' blocks (along
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/// with their common predecessor) forms a valid diamond shape for ifcvt.
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bool IfConverter::ValidDiamond(BBInfo &TrueBBI, BBInfo &FalseBBI) const {
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if (TrueBBI.IsBeingAnalyzed || FalseBBI.IsBeingAnalyzed)
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return false;
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MachineBasicBlock *TT = TrueBBI.TrueBB;
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MachineBasicBlock *FT = FalseBBI.TrueBB;
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@ -337,7 +354,7 @@ bool IfConverter::ValidDiamond(BBInfo &TrueBBI, BBInfo &FalseBBI) const {
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FT = getNextBlock(FalseBBI.BB);
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if (TT != FT)
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return false;
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if (TT == NULL && (TrueBBI.IsAnalyzable || FalseBBI.IsAnalyzable))
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if (TT == NULL && (TrueBBI.IsBrAnalyzable || FalseBBI.IsBrAnalyzable))
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return false;
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// FIXME: Allow false block to have an early exit?
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return (TrueBBI.BB->pred_size() == 1 &&
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@ -345,59 +362,155 @@ bool IfConverter::ValidDiamond(BBInfo &TrueBBI, BBInfo &FalseBBI) const {
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!TrueBBI.FalseBB && !FalseBBI.FalseBB);
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}
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/// AnalyzeBlock - Analyze the structure of the sub-CFG starting from
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/// the specified block. Record its successors and whether it looks like an
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/// if-conversion candidate.
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void IfConverter::AnalyzeBlock(MachineBasicBlock *BB) {
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BBInfo &BBI = BBAnalysis[BB->getNumber()];
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/// ScanInstructions - Scan all the instructions in the block to determine if
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/// the block is predicable. In most cases, that means all the instructions
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/// in the block has M_PREDICABLE flag. Also checks if the block contains any
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/// instruction which can clobber a predicate (e.g. condition code register).
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/// If so, the block is not predicable unless it's the last instruction.
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void IfConverter::ScanInstructions(BBInfo &BBI) {
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if (BBI.IsDone)
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return;
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if (BBI.Kind == ICReAnalyze) {
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// First analyze the end of BB branches.
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BBI.TrueBB = BBI.FalseBB;
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BBI.BrCond.clear();
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BBI.TrueBB = BBI.FalseBB = NULL;
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} else {
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if (BBI.Kind != ICNotAnalyzed)
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return; // Already analyzed.
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BBI.BB = BB;
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BBI.NonPredSize = std::distance(BB->begin(), BB->end());
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}
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// Look for 'root' of a simple (non-nested) triangle or diamond.
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BBI.Kind = ICNotClassfied;
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BBI.IsAnalyzable =
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!TII->AnalyzeBranch(*BB, BBI.TrueBB, BBI.FalseBB, BBI.BrCond);
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BBI.HasFallThrough = BBI.IsAnalyzable && BBI.FalseBB == NULL;
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// Unanalyable or ends with fallthrough or unconditional branch.
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if (!BBI.IsAnalyzable || BBI.BrCond.size() == 0)
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return;
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// Do not ifcvt if either path is a back edge to the entry block.
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if (BBI.TrueBB == BB || BBI.FalseBB == BB)
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return;
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AnalyzeBlock(BBI.TrueBB);
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BBInfo &TrueBBI = BBAnalysis[BBI.TrueBB->getNumber()];
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BBI.IsBrAnalyzable =
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!TII->AnalyzeBranch(*BBI.BB, BBI.TrueBB, BBI.FalseBB, BBI.BrCond);
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BBI.HasFallThrough = BBI.IsBrAnalyzable && BBI.FalseBB == NULL;
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if (BBI.BrCond.size()) {
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// No false branch. This BB must end with a conditional branch and a
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// fallthrough.
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if (!BBI.FalseBB)
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BBI.FalseBB = findFalseBlock(BB, BBI.TrueBB);
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BBI.FalseBB = findFalseBlock(BBI.BB, BBI.TrueBB);
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assert(BBI.FalseBB && "Expected to find the fallthrough block!");
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}
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AnalyzeBlock(BBI.FalseBB);
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BBInfo &FalseBBI = BBAnalysis[BBI.FalseBB->getNumber()];
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// Then scan all the instructions.
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BBI.NonPredSize = 0;
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BBI.ClobbersPred = false;
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bool SeenCondBr = false;
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for (MachineBasicBlock::iterator I = BBI.BB->begin(), E = BBI.BB->end();
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I != E; ++I) {
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const TargetInstrDescriptor *TID = I->getInstrDescriptor();
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bool isPredicated = TII->isPredicated(I);
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bool isCondBr = BBI.IsBrAnalyzable &&
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(TID->Flags & M_BRANCH_FLAG) != 0 && (TID->Flags & M_BARRIER_FLAG) == 0;
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// If both paths are dead, then forget about it.
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if (TrueBBI.Kind == ICDead && FalseBBI.Kind == ICDead) {
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BBI.Kind = ICDead;
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if (!isPredicated && !isCondBr)
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BBI.NonPredSize++;
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if (BBI.ClobbersPred && !isPredicated) {
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// Predicate modification instruction should end the block (except for
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// already predicated instructions and end of block branches).
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if (isCondBr) {
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SeenCondBr = true;
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// Conditional branches is not predicable. But it may be eliminated.
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continue;
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}
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// Predicate may have been modified, the subsequent (currently)
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// unpredocated instructions cannot be correctly predicated.
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BBI.IsUnpredicable = true;
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return;
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}
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// Look for more opportunities to if-convert a triangle. Try to restructure
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// the CFG to form a triangle with the 'false' path.
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if (TID->Flags & M_CLOBBERS_PRED)
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BBI.ClobbersPred = true;
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if (!I->isPredicable()) {
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BBI.IsUnpredicable = true;
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return;
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}
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}
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}
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/// FeasibilityAnalysis - Determine if the block is a suitable candidate to be
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/// predicated by the specified predicate.
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bool IfConverter::FeasibilityAnalysis(BBInfo &BBI,
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std::vector<MachineOperand> &Pred,
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bool isTriangle, bool RevBranch) {
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// Forget about it if it's unpredicable.
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if (BBI.IsUnpredicable)
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return false;
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// If the block is dead, or it is going to be the entry block of a sub-CFG
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// that will be if-converted, then it cannot be predicated.
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if (BBI.IsDone || BBI.IsEnqueued)
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return false;
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// Check predication threshold.
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if (BBI.NonPredSize == 0 || BBI.NonPredSize > TLI->getIfCvtBlockSizeLimit())
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return false;
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// If it is already predicated, check if its predicate subsumes the new
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// predicate.
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if (BBI.Predicate.size() && !TII->SubsumesPredicate(BBI.Predicate, Pred))
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return false;
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if (BBI.BrCond.size()) {
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if (!isTriangle)
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return false;
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// Test predicate subsumsion.
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std::vector<MachineOperand> RevPred(Pred);
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std::vector<MachineOperand> Cond(BBI.BrCond);
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if (RevBranch) {
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if (TII->ReverseBranchCondition(Cond))
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return false;
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}
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if (TII->ReverseBranchCondition(RevPred) ||
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!TII->SubsumesPredicate(Cond, RevPred))
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return false;
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}
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return true;
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}
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/// AnalyzeBlock - Analyze the structure of the sub-CFG starting from
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/// the specified block. Record its successors and whether it looks like an
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/// if-conversion candidate.
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IfConverter::BBInfo &IfConverter::AnalyzeBlock(MachineBasicBlock *BB) {
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BBInfo &BBI = BBAnalysis[BB->getNumber()];
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if (BBI.IsAnalyzed || BBI.IsBeingAnalyzed)
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return BBI;
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BBI.BB = BB;
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BBI.IsBeingAnalyzed = true;
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BBI.Kind = ICNotClassfied;
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ScanInstructions(BBI);
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// Unanalyable or ends with fallthrough or unconditional branch.
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if (!BBI.IsBrAnalyzable || BBI.BrCond.size() == 0) {
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BBI.IsBeingAnalyzed = false;
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BBI.IsAnalyzed = true;
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return BBI;
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}
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// Do not ifcvt if either path is a back edge to the entry block.
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if (BBI.TrueBB == BB || BBI.FalseBB == BB) {
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BBI.IsBeingAnalyzed = false;
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BBI.IsAnalyzed = true;
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return BBI;
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}
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BBInfo &TrueBBI = AnalyzeBlock(BBI.TrueBB);
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BBInfo &FalseBBI = AnalyzeBlock(BBI.FalseBB);
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if (TrueBBI.IsDone && FalseBBI.IsDone) {
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BBI.IsBeingAnalyzed = false;
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BBI.IsAnalyzed = true;
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return BBI;
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}
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std::vector<MachineOperand> RevCond(BBI.BrCond);
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bool CanRevCond = !TII->ReverseBranchCondition(RevCond);
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if (CanRevCond && ValidDiamond(TrueBBI, FalseBBI) &&
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!(TrueBBI.ModifyPredicate && FalseBBI.ModifyPredicate) &&
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!(TrueBBI.ClobbersPred && FalseBBI.ClobbersPred) &&
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FeasibilityAnalysis(TrueBBI, BBI.BrCond) &&
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FeasibilityAnalysis(FalseBBI, RevCond)) {
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// Diamond:
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@ -409,7 +522,6 @@ void IfConverter::AnalyzeBlock(MachineBasicBlock *BB) {
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// TailBB
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// Note TailBB can be empty.
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BBI.Kind = ICDiamond;
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TrueBBI.Kind = FalseBBI.Kind = ICChild;
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BBI.TailBB = TrueBBI.TrueBB;
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} else {
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// FIXME: Consider duplicating if BB is small.
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@ -423,7 +535,6 @@ void IfConverter::AnalyzeBlock(MachineBasicBlock *BB) {
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// | /
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// FBB
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BBI.Kind = ICTriangle;
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TrueBBI.Kind = ICChild;
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} else if (ValidSimple(TrueBBI) &&
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FeasibilityAnalysis(TrueBBI, BBI.BrCond)) {
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// Simple (split, no rejoin):
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@ -434,93 +545,24 @@ void IfConverter::AnalyzeBlock(MachineBasicBlock *BB) {
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// |
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// FBB
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BBI.Kind = ICSimple;
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TrueBBI.Kind = ICChild;
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} else if (CanRevCond) {
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// Try the other path...
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if (ValidTriangle(FalseBBI, TrueBBI) &&
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FeasibilityAnalysis(FalseBBI, RevCond, true)) {
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BBI.Kind = ICTriangleFalse;
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FalseBBI.Kind = ICChild;
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} else if (ValidTriangle(FalseBBI, TrueBBI, true) &&
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FeasibilityAnalysis(FalseBBI, RevCond, true, true)) {
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BBI.Kind = ICTriangleFRev;
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FalseBBI.Kind = ICChild;
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} else if (ValidSimple(FalseBBI) &&
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FeasibilityAnalysis(FalseBBI, RevCond)) {
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BBI.Kind = ICSimpleFalse;
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FalseBBI.Kind = ICChild;
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}
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}
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}
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return;
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}
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/// FeasibilityAnalysis - Determine if the block is predicable. In most
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/// cases, that means all the instructions in the block has M_PREDICABLE flag.
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/// Also checks if the block contains any instruction which can clobber a
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/// predicate (e.g. condition code register). If so, the block is not
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/// predicable unless it's the last instruction.
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bool IfConverter::FeasibilityAnalysis(BBInfo &BBI,
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std::vector<MachineOperand> &Pred,
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bool isTriangle, bool RevBranch) {
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// If the block is dead, or it is going to be the entry block of a sub-CFG
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// that will be if-converted, then it cannot be predicated.
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if (BBI.Kind != ICNotAnalyzed &&
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BBI.Kind != ICNotClassfied &&
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BBI.Kind != ICChild)
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return false;
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// Check predication threshold.
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if (BBI.NonPredSize == 0 || BBI.NonPredSize > TLI->getIfCvtBlockSizeLimit())
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return false;
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// If it is already predicated, check if its predicate subsumes the new
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// predicate.
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if (BBI.Predicate.size() && !TII->SubsumesPredicate(BBI.Predicate, Pred))
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return false;
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bool SeenPredMod = false;
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bool SeenCondBr = false;
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for (MachineBasicBlock::iterator I = BBI.BB->begin(), E = BBI.BB->end();
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I != E; ++I) {
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const TargetInstrDescriptor *TID = I->getInstrDescriptor();
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if (SeenPredMod) {
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// Predicate modification instruction should end the block (except for
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// already predicated instructions and end of block branches).
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if (!TII->isPredicated(I)) {
|
||||
// This is the 'true' block of a triangle, i.e. its 'true' block is
|
||||
// the same as the 'false' block of the entry. So false positive
|
||||
// is ok.
|
||||
if (isTriangle && !SeenCondBr && BBI.IsAnalyzable &&
|
||||
(TID->Flags & M_BRANCH_FLAG) != 0 &&
|
||||
(TID->Flags & M_BARRIER_FLAG) == 0) {
|
||||
// This is the first conditional branch, test predicate subsumsion.
|
||||
std::vector<MachineOperand> RevPred(Pred);
|
||||
std::vector<MachineOperand> Cond(BBI.BrCond);
|
||||
if (RevBranch) {
|
||||
if (TII->ReverseBranchCondition(Cond))
|
||||
return false;
|
||||
}
|
||||
if (TII->ReverseBranchCondition(RevPred) ||
|
||||
!TII->SubsumesPredicate(Cond, RevPred))
|
||||
return false;
|
||||
SeenCondBr = true;
|
||||
continue; // Conditional branches is not predicable.
|
||||
}
|
||||
return false;
|
||||
}
|
||||
}
|
||||
|
||||
if (TID->Flags & M_CLOBBERS_PRED) {
|
||||
BBI.ModifyPredicate = true;
|
||||
SeenPredMod = true;
|
||||
}
|
||||
|
||||
if (!I->isPredicable())
|
||||
return false;
|
||||
}
|
||||
|
||||
return true;
|
||||
BBI.IsBeingAnalyzed = false;
|
||||
BBI.IsAnalyzed = true;
|
||||
return BBI;
|
||||
}
|
||||
|
||||
/// AttemptRestructuring - Restructure the sub-CFG rooted in the given block to
|
||||
@ -561,8 +603,7 @@ bool IfConverter::AnalyzeBlocks(MachineFunction &MF,
|
||||
for (idf_ext_iterator<MachineBasicBlock*> I=idf_ext_begin(Roots[i],Visited),
|
||||
E = idf_ext_end(Roots[i], Visited); I != E; ++I) {
|
||||
MachineBasicBlock *BB = *I;
|
||||
AnalyzeBlock(BB);
|
||||
BBInfo &BBI = BBAnalysis[BB->getNumber()];
|
||||
BBInfo &BBI = AnalyzeBlock(BB);
|
||||
switch (BBI.Kind) {
|
||||
case ICSimple:
|
||||
case ICSimpleFalse:
|
||||
@ -602,8 +643,10 @@ void IfConverter::ReTryPreds(MachineBasicBlock *BB) {
|
||||
for (MachineBasicBlock::pred_iterator PI = BB->pred_begin(),
|
||||
E = BB->pred_end(); PI != E; ++PI) {
|
||||
BBInfo &PBBI = BBAnalysis[(*PI)->getNumber()];
|
||||
if (PBBI.Kind == ICNotClassfied)
|
||||
PBBI.Kind = ICReAnalyze;
|
||||
if (!PBBI.IsDone && PBBI.Kind == ICNotClassfied) {
|
||||
assert(PBBI.IsEnqueued && "Unexpected");
|
||||
PBBI.IsAnalyzed = false;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
@ -672,12 +715,10 @@ bool IfConverter::IfConvertSimple(BBInfo &BBI) {
|
||||
RemoveExtraEdges(BBI);
|
||||
|
||||
// Update block info. BB can be iteratively if-converted.
|
||||
if (IterIfcvt)
|
||||
BBI.Kind = ICReAnalyze;
|
||||
else
|
||||
BBI.Kind = ICDead;
|
||||
if (!IterIfcvt)
|
||||
BBI.IsDone = true;
|
||||
ReTryPreds(BBI.BB);
|
||||
CvtBBI->Kind = ICDead;
|
||||
CvtBBI->IsDone = true;
|
||||
|
||||
// FIXME: Must maintain LiveIns.
|
||||
return true;
|
||||
@ -703,7 +744,8 @@ bool IfConverter::IfConvertTriangle(BBInfo &BBI) {
|
||||
if (PBB == BBI.BB)
|
||||
continue;
|
||||
BBInfo &PBBI = BBAnalysis[PBB->getNumber()];
|
||||
PBBI.Kind = ICReAnalyze;
|
||||
if (PBBI.IsEnqueued)
|
||||
PBBI.IsEnqueued = false;
|
||||
}
|
||||
}
|
||||
std::swap(CvtBBI, NextBBI);
|
||||
@ -751,14 +793,12 @@ bool IfConverter::IfConvertTriangle(BBInfo &BBI) {
|
||||
RemoveExtraEdges(BBI);
|
||||
|
||||
// Update block info. BB can be iteratively if-converted.
|
||||
if (IterIfcvt)
|
||||
BBI.Kind = ICReAnalyze;
|
||||
else
|
||||
BBI.Kind = ICDead;
|
||||
if (!IterIfcvt)
|
||||
BBI.IsDone = true;
|
||||
ReTryPreds(BBI.BB);
|
||||
CvtBBI->Kind = ICDead;
|
||||
CvtBBI->IsDone = true;
|
||||
if (FalseBBDead)
|
||||
NextBBI->Kind = ICDead;
|
||||
NextBBI->IsDone = true;
|
||||
|
||||
// FIXME: Must maintain LiveIns.
|
||||
return true;
|
||||
@ -822,8 +862,8 @@ bool IfConverter::IfConvertDiamond(BBInfo &BBI) {
|
||||
bool NeedBr1 = !BBI1->TrueBB && BBI1->BB->succ_size();
|
||||
bool NeedBr2 = !BBI2->TrueBB && BBI2->BB->succ_size();
|
||||
|
||||
if ((TrueBBI.ModifyPredicate && !FalseBBI.ModifyPredicate) ||
|
||||
(!TrueBBI.ModifyPredicate && !FalseBBI.ModifyPredicate &&
|
||||
if ((TrueBBI.ClobbersPred && !FalseBBI.ClobbersPred) ||
|
||||
(!TrueBBI.ClobbersPred && !FalseBBI.ClobbersPred &&
|
||||
NeedBr1 && !NeedBr2)) {
|
||||
std::swap(BBI1, BBI2);
|
||||
std::swap(Cond1, Cond2);
|
||||
@ -878,15 +918,13 @@ bool IfConverter::IfConvertDiamond(BBInfo &BBI) {
|
||||
CvtBBI->NonPredSize -= TII->RemoveBranch(*CvtBBI->BB);
|
||||
BBInfo TailBBI = BBAnalysis[BBI.TailBB->getNumber()];
|
||||
MergeBlocks(*CvtBBI, TailBBI);
|
||||
TailBBI.Kind = ICDead;
|
||||
TailBBI.IsDone = true;
|
||||
}
|
||||
|
||||
RemoveExtraEdges(BBI);
|
||||
|
||||
// Update block info.
|
||||
BBI.Kind = ICDead;
|
||||
TrueBBI.Kind = ICDead;
|
||||
FalseBBI.Kind = ICDead;
|
||||
BBI.IsDone = TrueBBI.IsDone = FalseBBI.IsDone = true;
|
||||
|
||||
// FIXME: Must maintain LiveIns.
|
||||
return true;
|
||||
@ -953,7 +991,7 @@ void IfConverter::MergeBlocks(BBInfo &ToBBI, BBInfo &FromBBI) {
|
||||
ToBBI.NonPredSize += FromBBI.NonPredSize;
|
||||
FromBBI.NonPredSize = 0;
|
||||
|
||||
ToBBI.ModifyPredicate |= FromBBI.ModifyPredicate;
|
||||
ToBBI.ClobbersPred |= FromBBI.ClobbersPred;
|
||||
ToBBI.HasFallThrough = FromBBI.HasFallThrough;
|
||||
|
||||
std::copy(FromBBI.Predicate.begin(), FromBBI.Predicate.end(),
|
||||
|
||||
Loading…
Reference in New Issue
Block a user