vendor/llvm/llvm-trunk-r321017

1 files changed, 44 insertions, 11 deletions

diff --git a/lib/Analysis/ProfileSummaryInfo.cpp b/lib/Analysis/ProfileSummaryInfo.cpp
index 12b86daa602b..671744f93fb8 100644
--- a/lib/Analysis/ProfileSummaryInfo.cpp
+++ b/lib/Analysis/ProfileSummaryInfo.cpp
@@ -30,7 +30,7 @@ using namespace llvm;
 // considered cold).
 
 static cl::opt<int> ProfileSummaryCutoffHot(
-    "profile-summary-cutoff-hot", cl::Hidden, cl::init(999000), cl::ZeroOrMore,
+    "profile-summary-cutoff-hot", cl::Hidden, cl::init(990000), cl::ZeroOrMore,
     cl::desc("A count is hot if it exceeds the minimum count to"
              " reach this percentile of total counts."));
 
@@ -39,9 +39,21 @@ static cl::opt<int> ProfileSummaryCutoffCold(
     cl::desc("A count is cold if it is below the minimum count"
              " to reach this percentile of total counts."));
 
-// Find the minimum count to reach a desired percentile of counts.
-static uint64_t getMinCountForPercentile(SummaryEntryVector &DS,
-                                         uint64_t Percentile) {
+static cl::opt<bool> ProfileSampleAccurate(
+    "profile-sample-accurate", cl::Hidden, cl::init(false),
+    cl::desc("If the sample profile is accurate, we will mark all un-sampled "
+             "callsite as cold. Otherwise, treat un-sampled callsites as if "
+             "we have no profile."));
+static cl::opt<unsigned> ProfileSummaryHugeWorkingSetSizeThreshold(
+    "profile-summary-huge-working-set-size-threshold", cl::Hidden,
+    cl::init(15000), cl::ZeroOrMore,
+    cl::desc("The code working set size is considered huge if the number of"
+             " blocks required to reach the -profile-summary-cutoff-hot"
+             " percentile exceeds this count."));
+
+// Find the summary entry for a desired percentile of counts.
+static const ProfileSummaryEntry &getEntryForPercentile(SummaryEntryVector &DS,
+                                                        uint64_t Percentile) {
   auto Compare = [](const ProfileSummaryEntry &Entry, uint64_t Percentile) {
     return Entry.Cutoff < Percentile;
   };
@@ -50,7 +62,7 @@ static uint64_t getMinCountForPercentile(SummaryEntryVector &DS,
   // detailed summary.
   if (It == DS.end())
     report_fatal_error("Desired percentile exceeds the maximum cutoff");
-  return It->MinCount;
+  return *It;
 }
 
 // The profile summary metadata may be attached either by the frontend or by
@@ -78,10 +90,12 @@ ProfileSummaryInfo::getProfileCount(const Instruction *Inst,
   if (hasSampleProfile()) {
     // In sample PGO mode, check if there is a profile metadata on the
     // instruction. If it is present, determine hotness solely based on that,
-    // since the sampled entry count may not be accurate.
+    // since the sampled entry count may not be accurate. If there is no
+    // annotated on the instruction, return None.
     uint64_t TotalCount;
     if (Inst->extractProfTotalWeight(TotalCount))
       return TotalCount;
+    return None;
   }
   if (BFI)
     return BFI->getBlockProfileCount(Inst->getParent());
@@ -161,10 +175,20 @@ void ProfileSummaryInfo::computeThresholds() {
   if (!computeSummary())
     return;
   auto &DetailedSummary = Summary->getDetailedSummary();
-  HotCountThreshold =
-      getMinCountForPercentile(DetailedSummary, ProfileSummaryCutoffHot);
-  ColdCountThreshold =
-      getMinCountForPercentile(DetailedSummary, ProfileSummaryCutoffCold);
+  auto &HotEntry =
+      getEntryForPercentile(DetailedSummary, ProfileSummaryCutoffHot);
+  HotCountThreshold = HotEntry.MinCount;
+  auto &ColdEntry =
+      getEntryForPercentile(DetailedSummary, ProfileSummaryCutoffCold);
+  ColdCountThreshold = ColdEntry.MinCount;
+  HasHugeWorkingSetSize =
+      HotEntry.NumCounts > ProfileSummaryHugeWorkingSetSizeThreshold;
+}
+
+bool ProfileSummaryInfo::hasHugeWorkingSetSize() {
+  if (!HasHugeWorkingSetSize)
+    computeThresholds();
+  return HasHugeWorkingSetSize && HasHugeWorkingSetSize.getValue();
 }
 
 bool ProfileSummaryInfo::isHotCount(uint64_t C) {
@@ -199,7 +223,16 @@ bool ProfileSummaryInfo::isHotCallSite(const CallSite &CS,
 bool ProfileSummaryInfo::isColdCallSite(const CallSite &CS,
                                         BlockFrequencyInfo *BFI) {
   auto C = getProfileCount(CS.getInstruction(), BFI);
-  return C && isColdCount(*C);
+  if (C)
+    return isColdCount(*C);
+
+  // In SamplePGO, if the caller has been sampled, and there is no profile
+  // annotatedon the callsite, we consider the callsite as cold.
+  // If there is no profile for the caller, and we know the profile is
+  // accurate, we consider the callsite as cold.
+  return (hasSampleProfile() &&
+          (CS.getCaller()->getEntryCount() || ProfileSampleAccurate ||
+           CS.getCaller()->hasFnAttribute("profile-sample-accurate")));
 }
 
 INITIALIZE_PASS(ProfileSummaryInfoWrapperPass, "profile-summary-info",