[llvm-cov] reset executation count to 0 after wrapped segment

Fix the bug: https://bugs.llvm.org/show_bug.cgi?id=36979. It also fixes this bug: https://bugs.llvm.org/show_bug.cgi?id=35404, which I think is caused by the same problem.

Differential Revision: https://reviews.llvm.org/D85036

Author: ZequanWu

llvm/lib/ProfileData/Coverage/CoverageMapping.cpp

@@ -770,6 +770,7 @@ LineCoverageStats::LineCoverageStats(
     ExecutionCount = WrappedSegment->Count;
   if (!MinRegionCount)
     return;
+  ExecutionCount = 0;
   for (const auto *LS : LineSegments)
     if (isStartOfRegion(LS))
       ExecutionCount = std::max(ExecutionCount, LS->Count);

llvm/test/tools/llvm-cov/Inputs/instrprof-comdat.h

@@ -12,7 +12,7 @@ template <class T> T FOO<T>::DoIt(T ti) { // HEADER: [[@LINE]]|  2|template
   for (T I = 0; I < ti; I++) {            // HEADER: [[@LINE]]| 22|  for (T
     t += I;                               // HEADER: [[@LINE]]| 20|   t += I;
     if (I > ti / 2)                       // HEADER: [[@LINE]]| 20|   if (I > ti
-      t -= 1;                             // HEADER: [[@LINE]]| 20|     t -= 1;
+      t -= 1;                             // HEADER: [[@LINE]]|  8|     t -= 1;
   }                                       // HEADER: [[@LINE]]| 20| }
                                           // HEADER: [[@LINE]]|  2|
   return t;                               // HEADER: [[@LINE]]|  2|  return t;

llvm/test/tools/llvm-cov/ignore-filename-regex.test

@@ -22,7 +22,7 @@ REPORT_IGNORE_DIR-NOT: {{.*}}extra{{[/\\]}}dec.h{{.*}}
 REPORT_IGNORE_DIR-NOT: {{.*}}extra{{[/\\]}}inc.h{{.*}}
 REPORT_IGNORE_DIR: {{.*}}abs.h{{.*}}
 REPORT_IGNORE_DIR: {{.*}}main.cc{{.*}}
-REPORT_IGNORE_DIR: {{^}}TOTAL 5{{.*}}100.00%{{$}}
+REPORT_IGNORE_DIR: {{^}}TOTAL 5{{.*}}90.00%{{$}}
 
 # Ignore all files from "extra" directory even when SOURCES specified.
 RUN: llvm-cov report -instr-profile %S/Inputs/sources_specified/main.profdata \
@@ -35,7 +35,7 @@ REPORT_IGNORE_DIR_WITH_SOURCES-NOT: {{.*}}extra{{[/\\]}}dec.h{{.*}}
 REPORT_IGNORE_DIR_WITH_SOURCES-NOT: {{.*}}extra{{[/\\]}}inc.h{{.*}}
 REPORT_IGNORE_DIR_WITH_SOURCES-NOT: {{.*}}main.cc{{.*}}
 REPORT_IGNORE_DIR_WITH_SOURCES: {{.*}}abs.h{{.*}}
-REPORT_IGNORE_DIR_WITH_SOURCES: {{^}}TOTAL 4{{.*}}100.00%{{$}}
+REPORT_IGNORE_DIR_WITH_SOURCES: {{^}}TOTAL 4{{.*}}80.00%{{$}}
 
 ########################
 # Test "show" command.

llvm/unittests/ProfileData/CoverageMappingTest.cpp

@@ -675,7 +675,7 @@ TEST_P(CoverageMappingTest, test_line_coverage_iterator) {
   CoverageData Data = LoadedCoverage->getCoverageForFile("file1");
 
   unsigned Line = 0;
-  unsigned LineCounts[] = {20, 20, 20, 20, 30, 10, 10, 10, 10, 0, 0};
+  unsigned LineCounts[] = {20, 20, 20, 20, 10, 10, 10, 10, 10, 0, 0};
   for (const auto &LCS : getLineCoverageStats(Data)) {
     ASSERT_EQ(Line + 1, LCS.getLine());
     errs() << "Line: " << Line + 1 << ", count = " << LCS.getExecutionCount() << "\n";