[llvm-branch-commits] [compiler-rt] [llvm] [Coverage] Make SingleByteCoverage work consistent to merging (PR #110972)

[NAKAMURA Takumi via llvm-branch-commits]

https://github.com/chapuni created https://github.com/llvm/llvm-project/pull/110972

- Round `Counts` as 1/0
- Confirm both `ExecutionCount` and `AltExecutionCount` are in range.

>From aacb50ddf87d96b4a0644c7ef5d0a86dc94f069b Mon Sep 17 00:00:00 2001
From: NAKAMURA Takumi <geek4civic at gmail.com>
Date: Wed, 2 Oct 2024 23:25:52 +0900
Subject: [PATCH] [Coverage] Make SingleByteCoverage work consistent to merging

- Round `Counts` as 1/0
- Confirm both `ExecutionCount` and `AltExecutionCount` are in range.
---
 compiler-rt/test/profile/instrprof-block-coverage.c | 2 +-
 compiler-rt/test/profile/instrprof-entry-coverage.c | 2 +-
 llvm/include/llvm/ProfileData/InstrProf.h           | 5 ++++-
 llvm/lib/ProfileData/Coverage/CoverageMapping.cpp   | 3 +++
 llvm/lib/ProfileData/InstrProf.cpp                  | 2 +-
 llvm/lib/ProfileData/InstrProfReader.cpp            | 1 +
 6 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/compiler-rt/test/profile/instrprof-block-coverage.c b/compiler-rt/test/profile/instrprof-block-coverage.c
index 829d5af8dc3f9e..8d924e1cac64d8 100644
--- a/compiler-rt/test/profile/instrprof-block-coverage.c
+++ b/compiler-rt/test/profile/instrprof-block-coverage.c
@@ -49,4 +49,4 @@ int main(int argc, char *argv[]) {
 
 // CHECK-ERROR-NOT: warning: {{.*}}: Found inconsistent block coverage
 
-// COUNTS: Maximum function count: 4
+// COUNTS: Maximum function count: 1
diff --git a/compiler-rt/test/profile/instrprof-entry-coverage.c b/compiler-rt/test/profile/instrprof-entry-coverage.c
index 1c6816ba01964b..b93a4e0c43ccd6 100644
--- a/compiler-rt/test/profile/instrprof-entry-coverage.c
+++ b/compiler-rt/test/profile/instrprof-entry-coverage.c
@@ -36,4 +36,4 @@ int main(int argc, char *argv[]) {
 // CHECK-DAG: foo
 // CHECK-DAG: bar
 
-// COUNTS: Maximum function count: 2
+// COUNTS: Maximum function count: 1
diff --git a/llvm/include/llvm/ProfileData/InstrProf.h b/llvm/include/llvm/ProfileData/InstrProf.h
index b0b2258735e2ae..df9e76966bf42b 100644
--- a/llvm/include/llvm/ProfileData/InstrProf.h
+++ b/llvm/include/llvm/ProfileData/InstrProf.h
@@ -830,6 +830,7 @@ struct InstrProfValueSiteRecord {
 /// Profiling information for a single function.
 struct InstrProfRecord {
   std::vector<uint64_t> Counts;
+  bool SingleByteCoverage = false;
   std::vector<uint8_t> BitmapBytes;
 
   InstrProfRecord() = default;
@@ -839,13 +840,15 @@ struct InstrProfRecord {
       : Counts(std::move(Counts)), BitmapBytes(std::move(BitmapBytes)) {}
   InstrProfRecord(InstrProfRecord &&) = default;
   InstrProfRecord(const InstrProfRecord &RHS)
-      : Counts(RHS.Counts), BitmapBytes(RHS.BitmapBytes),
+      : Counts(RHS.Counts), SingleByteCoverage(RHS.SingleByteCoverage),
+        BitmapBytes(RHS.BitmapBytes),
         ValueData(RHS.ValueData
                       ? std::make_unique<ValueProfData>(*RHS.ValueData)
                       : nullptr) {}
   InstrProfRecord &operator=(InstrProfRecord &&) = default;
   InstrProfRecord &operator=(const InstrProfRecord &RHS) {
     Counts = RHS.Counts;
+    SingleByteCoverage = RHS.SingleByteCoverage;
     BitmapBytes = RHS.BitmapBytes;
     if (!RHS.ValueData) {
       ValueData = nullptr;
diff --git a/llvm/lib/ProfileData/Coverage/CoverageMapping.cpp b/llvm/lib/ProfileData/Coverage/CoverageMapping.cpp
index a02136d5b0386d..bc765c59381718 100644
--- a/llvm/lib/ProfileData/Coverage/CoverageMapping.cpp
+++ b/llvm/lib/ProfileData/Coverage/CoverageMapping.cpp
@@ -874,6 +874,9 @@ Error CoverageMapping::loadFunctionRecord(
       consumeError(std::move(E));
       return Error::success();
     }
+    assert(!SingleByteCoverage ||
+           (0 <= *ExecutionCount && *ExecutionCount <= 1 &&
+            0 <= *AltExecutionCount && *AltExecutionCount <= 1));
     Function.pushRegion(Region, *ExecutionCount, *AltExecutionCount);
 
     // Record ExpansionRegion.
diff --git a/llvm/lib/ProfileData/InstrProf.cpp b/llvm/lib/ProfileData/InstrProf.cpp
index b9937c9429b77d..0f6677b4d35718 100644
--- a/llvm/lib/ProfileData/InstrProf.cpp
+++ b/llvm/lib/ProfileData/InstrProf.cpp
@@ -952,7 +952,7 @@ void InstrProfRecord::merge(InstrProfRecord &Other, uint64_t Weight,
       Value = getInstrMaxCountValue();
       Overflowed = true;
     }
-    Counts[I] = Value;
+    Counts[I] = (SingleByteCoverage && Value != 0 ? 1 : Value);
     if (Overflowed)
       Warn(instrprof_error::counter_overflow);
   }
diff --git a/llvm/lib/ProfileData/InstrProfReader.cpp b/llvm/lib/ProfileData/InstrProfReader.cpp
index b90617c74f6d13..a07d7f573275ba 100644
--- a/llvm/lib/ProfileData/InstrProfReader.cpp
+++ b/llvm/lib/ProfileData/InstrProfReader.cpp
@@ -743,6 +743,7 @@ Error RawInstrProfReader<IntPtrT>::readRawCounts(
 
   Record.Counts.clear();
   Record.Counts.reserve(NumCounters);
+  Record.SingleByteCoverage = hasSingleByteCoverage();
   for (uint32_t I = 0; I < NumCounters; I++) {
     const char *Ptr =
         CountersStart + CounterBaseOffset + I * getCounterTypeSize();