[llvm-cov] Correctly export branch coverage in LCOV format

[fetzerch]

Summary

Commit 9f2967bcfe2f7d1fc02281f0098306c90c2c10a5 introduced support for
branch coverage including export to the LCOV format.

This commit corrects the LCOV field name for branches from BFH to BRH.
The mistake seems to have slipped in as typo because the correct field
name BRH is used in the comment section at the beginning of the file.

See also https://github.com/linux-test-project/lcov/blob/d100e6cdd4c67cbe5322fa26b2ee8aa34ea7ebcf/man/geninfo.1#L561
for the LCOV format specification.

[alanphipps]

Thank you for catching this! LGTM. Can you please ensure this defect fix blocks 12.x and 13.x release branches as well?

[fetzerch]

Thanks! This is my first contribution to LLVM and I don't have commit permissions. Could you or some of the maintainers please commit it on my behalf (Christian Fetzer <[e-mail]>)? What would I need to do to 'block 12.x and 13.x release branches'?

[alanphipps]

In D108358#2954926, @fetzerch wrote:

Thanks! This is my first contribution to LLVM and I don't have commit permissions. Could you or some of the maintainers please commit it on my behalf (Christian Fetzer <[e-mail]>)? What would I need to do to 'block 12.x and 13.x release branches'?

Certainly, I can commit this for you with you as author. It'll probably be within the next day or so.

For the 12.x/13.x release branches, it requires creating a bugzilla record and noting the commit. I've done this once before, but I'll take care of it.

[fetzerch]

In D108358#2954968, @alanphipps wrote:

In D108358#2954926, @fetzerch wrote:

Thanks! This is my first contribution to LLVM and I don't have commit permissions. Could you or some of the maintainers please commit it on my behalf (Christian Fetzer <[e-mail]>)? What would I need to do to 'block 12.x and 13.x release branches'?

Certainly, I can commit this for you with you as author. It'll probably be within the next day or so.

For the 12.x/13.x release branches, it requires creating a bugzilla record and noting the commit. I've done this once before, but I'll take care of it.

Thanks, much appreciated!

llvm/test/tools/llvm-cov/branch-export-lcov.test

 // CHECK-DAG: BRDA:45,0,0,0
 // CHECK-DAG: BRDA:45,0,1,5
 // CHECK-DAG: BRDA:47,0,0,3
 // CHECK-DAG: BRDA:47,0,1,2
 // CHECK-DAG: BRDA:53,0,0,50
 // CHECK-DAG: BRDA:53,0,1,5
 // CHECK-NOT: BRDA
 // CHECK: BRF:30
-// CHECK: BFH:26
+// CHECK: BRH:26
 
 // Check recursive macro-expansions.
 // RUN: llvm-profdata merge %S/Inputs/branch-macros.proftext -o %t.profdata
 // RUN: llvm-cov export --format=lcov %S/Inputs/branch-macros.o32l -instr-profile %t.profdata | FileCheck %s -check-prefix=MACROS
 
 // MACROS-COUNT-4: BRDA:17
 // MACROS-NOT: BRDA:17
 

 // MACROS: BRDA:27,3,7,-
 // MACROS: BRDA:27,4,8,-
 // MACROS: BRDA:27,4,9,-
 
 // MACROS-COUNT-10: BRDA:37
 // MACROS-NOT: BRDA:37
 // MACROS-NOT: BRDA
 // MACROS: BRF:40
-// MACROS: BFH:24
+// MACROS: BRH:24

llvm/tools/llvm-cov/CoverageExporterLcov.cpp

 
 void renderLineSummary(raw_ostream &OS, const FileCoverageSummary &Summary) {
   OS << "LF:" << Summary.LineCoverage.getNumLines() << '\n'
      << "LH:" << Summary.LineCoverage.getCovered() << '\n';
 }
 
 void renderBranchSummary(raw_ostream &OS, const FileCoverageSummary &Summary) {
   OS << "BRF:" << Summary.BranchCoverage.getNumBranches() << '\n'
-     << "BFH:" << Summary.BranchCoverage.getCovered() << '\n';
+     << "BRH:" << Summary.BranchCoverage.getCovered() << '\n';
 }
 
 void renderFile(raw_ostream &OS, const coverage::CoverageMapping &Coverage,
                 const std::string &Filename,
                 const FileCoverageSummary &FileReport, bool ExportSummaryOnly,
                 bool SkipFunctions) {
   OS << "SF:" << Filename << '\n';