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Increase number of icmps needed for converting to a switch statement #99269

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Increase number of icmps needed for converting to a switch statement #99269

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8 changes: 6 additions & 2 deletions llvm/lib/Transforms/Utils/SimplifyCFG.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -180,6 +180,10 @@ static cl::opt<unsigned> MaxSwitchCasesPerResult(
"max-switch-cases-per-result", cl::Hidden, cl::init(16),
cl::desc("Limit cases to analyze when converting a switch to select"));

static cl::opt<unsigned> MinICmpsToSwitch(
"min-icmps-to-switch", cl::Hidden, cl::init(9),
cl::desc("Minimum number of icmp sequences to convert to switch"));

STATISTIC(NumBitMaps, "Number of switch instructions turned into bitmaps");
STATISTIC(NumLinearMaps,
"Number of switch instructions turned into linear mapping");
Expand Down Expand Up @@ -4893,8 +4897,8 @@ bool SimplifyCFGOpt::SimplifyBranchOnICmpChain(BranchInst *BI,
if (!CompVal)
return false;

// Avoid turning single icmps into a switch.
if (UsedICmps <= 1)
// Avoid turning few icmps into a switch.
if (UsedICmps < MinICmpsToSwitch)
return false;

bool TrueWhenEqual = match(Cond, m_LogicalOr(m_Value(), m_Value()));
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