[llvm-branch-commits] [llvm] fed4134 - Revert "Revert "[Coverage] Fix branch coverage merging in FunctionCoverageSummary::get() for instantiation""

[Tom Stellard via llvm-branch-commits]

Author: Tom Stellard
Date: 2021-06-28T09:23:38-07:00
New Revision: fed41342a82f5a3a9201819a82bf7a48313e296b

URL: https://github.com/llvm/llvm-project/commit/fed41342a82f5a3a9201819a82bf7a48313e296b
DIFF: https://github.com/llvm/llvm-project/commit/fed41342a82f5a3a9201819a82bf7a48313e296b.diff

LOG: Revert "Revert "[Coverage] Fix branch coverage merging in FunctionCoverageSummary::get() for instantiation""

This reverts commit 33d312b2d731507327252fd597bac1b738870330.

The original patch was correct, so we need to restore it in the
release branch.

Added: 
    

Modified: 
    llvm/test/tools/llvm-cov/branch-templates.cpp
    llvm/tools/llvm-cov/CoverageSummaryInfo.cpp
    llvm/tools/llvm-cov/CoverageSummaryInfo.h

Removed: 
    


################################################################################
diff  --git a/llvm/test/tools/llvm-cov/branch-templates.cpp b/llvm/test/tools/llvm-cov/branch-templates.cpp
index 750dc7bd58f27..4797428f8835a 100644
--- a/llvm/test/tools/llvm-cov/branch-templates.cpp
+++ b/llvm/test/tools/llvm-cov/branch-templates.cpp
@@ -1,9 +1,9 @@
 // RUN: llvm-profdata merge %S/Inputs/branch-templates.proftext -o %t.profdata
 // RUN: llvm-cov show --show-expansions --show-branches=count %S/Inputs/branch-templates.o32l -instr-profile %t.profdata -path-equivalence=/tmp,%S %s | FileCheck %s
 // RUN: llvm-cov report --show-branch-summary %S/Inputs/branch-templates.o32l -instr-profile %t.profdata -show-functions -path-equivalence=/tmp,%S %s | FileCheck %s -check-prefix=REPORT
+// RUN: llvm-cov report --show-branch-summary %S/Inputs/branch-templates.o32l -instr-profile %t.profdata -path-equivalence=/tmp,%S %s | FileCheck %s -check-prefix=REPORTFILE
 
 #include <stdio.h>
-
 template<typename T>
 void unused(T x) {
   return;
@@ -45,3 +45,17 @@ int main() {
 // REPORT-NEXT: _Z4funcIfEiT_                     5       2  60.00%         7       3  57.14%         2       1  50.00%
 // REPORT-NEXT: ---
 // REPORT-NEXT: TOTAL                            22       7  68.18%        31      11  64.52%        12       6  50.00%
+
+// Make sure the covered branch tally for the function instantiation group is
+// merged to reflect maximum branch coverage of a single instantiation, just
+// like what is done for lines and regions. Also, the total branch tally
+// summary for an instantiation group should agree with the total number of
+// branches in the definition (In this case, 2 and 6 for func<>() and main(),
+// respectively).  This is returned by: FunctionCoverageSummary::get(const
+// InstantiationGroup &Group, ...)
+
+// REPORTFILE: Filename                      Regions    Missed Regions     Cover   Functions  Missed Functions  Executed       Lines      Missed Lines     Cover    Branches   Missed Branches     Cover
+// REPORTFILE-NEXT: ---
+// REPORTFILE-NEXT: branch-templates.cpp          12                 3    75.00%           2                 0   100.00%          17                 4    76.47%           8                 4    50.00%
+// REPORTFILE-NEXT: ---
+// REPORTFILE-NEXT: TOTAL                              12                 3    75.00%           2                 0   100.00%          17                 4    76.47%           8                 4    50.00%

diff  --git a/llvm/tools/llvm-cov/CoverageSummaryInfo.cpp b/llvm/tools/llvm-cov/CoverageSummaryInfo.cpp
index 4a0a86168908f..10e059adeb7d8 100644
--- a/llvm/tools/llvm-cov/CoverageSummaryInfo.cpp
+++ b/llvm/tools/llvm-cov/CoverageSummaryInfo.cpp
@@ -100,11 +100,7 @@ FunctionCoverageSummary::get(const InstantiationGroup &Group,
   for (const auto &FCS : Summaries.drop_front()) {
     Summary.RegionCoverage.merge(FCS.RegionCoverage);
     Summary.LineCoverage.merge(FCS.LineCoverage);
-
-    // Sum branch coverage across instantiation groups for the summary rather
-    // than "merge" the maximum count. This is a clearer view into whether all
-    // created branches are covered.
-    Summary.BranchCoverage += FCS.BranchCoverage;
+    Summary.BranchCoverage.merge(FCS.BranchCoverage);
   }
   return Summary;
 }

diff  --git a/llvm/tools/llvm-cov/CoverageSummaryInfo.h b/llvm/tools/llvm-cov/CoverageSummaryInfo.h
index 4bc1c24a079f2..62e7cad1012b1 100644
--- a/llvm/tools/llvm-cov/CoverageSummaryInfo.h
+++ b/llvm/tools/llvm-cov/CoverageSummaryInfo.h
@@ -123,6 +123,11 @@ class BranchCoverageInfo {
     return *this;
   }
 
+  void merge(const BranchCoverageInfo &RHS) {
+    Covered = std::max(Covered, RHS.Covered);
+    NumBranches = std::max(NumBranches, RHS.NumBranches);
+  }
+
   size_t getCovered() const { return Covered; }
 
   size_t getNumBranches() const { return NumBranches; }