OptSizeThreshold < Threshold)
Threshold = OptSizeThreshold;
- // Listen to the inlinehint attribute when it would increase the threshold
- // and the caller does not need to minimize its size.
Function *Callee = CS.getCalledFunction();
- bool InlineHint = Callee && !Callee->isDeclaration() &&
- Callee->hasFnAttribute(Attribute::InlineHint);
+ if (!Callee || Callee->isDeclaration())
+ return Threshold;
+
+ // If profile information is available, use that to adjust threshold of hot
+ // and cold functions.
+ // FIXME: The heuristic used below for determining hotness and coldness are
+ // based on preliminary SPEC tuning and may not be optimal. Replace this with
+ // a well-tuned heuristic based on *callsite* hotness and not callee hotness.
+ uint64_t FunctionCount = 0, MaxFunctionCount = 0;
+ bool HasPGOCounts = false;
+ if (Callee->getEntryCount() &&
+ Callee->getParent()->getMaximumFunctionCount()) {
+ HasPGOCounts = true;
+ FunctionCount = Callee->getEntryCount().getValue();
+ MaxFunctionCount =
+ Callee->getParent()->getMaximumFunctionCount().getValue();
+ }
+
+ // Listen to the inlinehint attribute or profile based hotness information
+ // when it would increase the threshold and the caller does not need to
+ // minimize its size.
+ bool InlineHint =
+ Callee->hasFnAttribute(Attribute::InlineHint) ||
+ (HasPGOCounts &&
+ FunctionCount >= (uint64_t)(0.3 * (double)MaxFunctionCount));
if (InlineHint && HintThreshold > Threshold &&
!Caller->hasFnAttribute(Attribute::MinSize))
Threshold = HintThreshold;
- // Listen to the cold attribute when it would decrease the threshold.
- bool ColdCallee = Callee && !Callee->isDeclaration() &&
- Callee->hasFnAttribute(Attribute::Cold);
+ // Listen to the cold attribute or profile based coldness information
+ // when it would decrease the threshold.
+ bool ColdCallee =
+ Callee->hasFnAttribute(Attribute::Cold) ||
+ (HasPGOCounts &&
+ FunctionCount <= (uint64_t)(0.01 * (double)MaxFunctionCount));
// Command line argument for InlineLimit will override the default
// ColdThreshold. If we have -inline-threshold but no -inlinecold-threshold,
// do not use the default cold threshold even if it is smaller.