[Coverage] Emit gap region after conditions when macro is present.

[zequanwu]

Summary

Bug filed here: https://bugs.llvm.org/show_bug.cgi?id=45849
This is caused by gap area not emitted if either AfterLoc or BeforeLoc is a macro location.

[vsk]

clang/test/CoverageMapping/macro-expressions.cpp

64

The gap region appears to start from the 'E' in 'EXPR'. That looks like it's too early -- I'd expect it to start after the final closing parenthesis ")".

78

Ditto.

[zequanwu]

Address comments.

[vsk]

Thanks, looks good to me! Please check for any issues in a stage2 coverage build before landing this.

[zequanwu]

Here is a repro of crash caused by this change.

int k, l;
#define m(e) e##e
void p() {
  int kk,ll;
  if (k)
    m(k);
  else
    l = m(l);
}

SM.getExpansLoc(AfterLoc) for m(k) gives location pointing to m(l), which caused the crash.

[phosek]

We started seeing assertion failure after rolling a toolchain that contains this change and git bisect identified this change. I have filed a bug with a reproducer as PR47324.

[zequanwu]

In D85176#2241257, @phosek wrote:

We started seeing assertion failure after rolling a toolchain that contains this change and git bisect identified this change. I have filed a bug with a reproducer as PR47324.

It has been reverted for now.

[zequanwu]

Tested on clange stage2 build.

[vsk]

Could you check in the reproducer program (void p) as a regression test?

clang/lib/CodeGen/CoverageMappingGen.cpp

995

It could aid debugging to assert that the result of getIncludeOrExpansionLoc(AfterLoc) is valid.

clang/test/CoverageMapping/if.cpp

10

Just to double-check: this is now starting the gap after the '?', instead of including the '?' - if so, that looks right.

[zequanwu]

• Added regression test.
• Assert getIncludeOrExpansionLoc(AfterLoc) is valid.

clang/test/CoverageMapping/if.cpp

10

Yes.

[vsk]

Thanks!

[zequanwu]

Landed at https://github.com/llvm/llvm-project/commit/d83511dd26ca8d0dd5be6302ad7b55de05cedab2 (forgot to add the differential revision line).

[saugustine]

This commit introduced an unused variable warning when built without asserts. (CoverageMappingGen.cpp:984) I have fixed it with rG4544a63b7705.

[zequanwu]

In D85176#2572661, @saugustine wrote:

This commit introduced an unused variable warning when built without asserts. (CoverageMappingGen.cpp:984) I have fixed it with rG4544a63b7705.

Thanks.

clang/lib/CodeGen/CoverageMappingGen.cpp

void terminateRegion(const Stmt *S) {
     auto &ZeroRegion = getRegion();
     ZeroRegion.setDeferred(true);
     LastTerminatedRegion = {EndLoc, RegionStack.size()};
   }
 
   /// Find a valid gap range between \p AfterLoc and \p BeforeLoc.
   Optional<SourceRange> findGapAreaBetween(SourceLocation AfterLoc,
                                            SourceLocation BeforeLoc) {
+    size_t StartDepth = locationDepth(AfterLoc);
+    size_t EndDepth = locationDepth(BeforeLoc);
+    while (!SM.isWrittenInSameFile(AfterLoc, BeforeLoc)) {
+      bool UnnestStart = StartDepth >= EndDepth;
+      bool UnnestEnd = EndDepth >= StartDepth;
+      if (UnnestEnd) {
+        SourceLocation NestedLoc = getStartOfFileOrMacro(BeforeLoc);
+        assert(SM.isWrittenInSameFile(NestedLoc, BeforeLoc));
+
+        BeforeLoc = getIncludeOrExpansionLoc(BeforeLoc);
+        assert(BeforeLoc.isValid());
+        EndDepth--;
+      }
+      if (UnnestStart) {
+        SourceLocation NestedLoc = getEndOfFileOrMacro(AfterLoc);
+        assert(SM.isWrittenInSameFile(AfterLoc, NestedLoc));
+
+        AfterLoc = getIncludeOrExpansionLoc(AfterLoc);
+        assert(AfterLoc.isValid());
+        AfterLoc = getPreciseTokenLocEnd(AfterLoc);
+        assert(AfterLoc.isValid());
+        StartDepth--;
+      }
+    }
+    AfterLoc = getPreciseTokenLocEnd(AfterLoc);
     // If the start and end locations of the gap are both within the same macro
     // file, the range may not be in source order.
     if (AfterLoc.isMacroID() || BeforeLoc.isMacroID())
       return None;
     if (!SM.isWrittenInSameFile(AfterLoc, BeforeLoc))
       return None;
     return {{AfterLoc, BeforeLoc}};
   }
 
-  /// Find the source range after \p AfterStmt and before \p BeforeStmt.
-  Optional<SourceRange> findGapAreaBetween(const Stmt *AfterStmt,
-                                           const Stmt *BeforeStmt) {
-    return findGapAreaBetween(getPreciseTokenLocEnd(getEnd(AfterStmt)),
-                              getStart(BeforeStmt));
-  }
-
   /// Emit a gap region between \p StartLoc and \p EndLoc with the given count.
   void fillGapAreaWithCount(SourceLocation StartLoc, SourceLocation EndLoc,
                             Counter Count) {
     if (StartLoc == EndLoc)
       return;
     assert(SpellingRegion(SM, StartLoc, EndLoc).isInSourceOrder());
     handleFileExit(StartLoc);
     size_t Index = pushRegion(Count, StartLoc, EndLoc);
void VisitWhileStmt(const WhileStmt *S) {
 
     // Go back to handle the condition.
     Counter CondCount =
         addCounters(ParentCount, BackedgeCount, BC.ContinueCount);
     propagateCounts(CondCount, S->getCond());
     adjustForOutOfOrderTraversal(getEnd(S));
 
     // The body count applies to the area immediately after the increment.
-    auto Gap = findGapAreaBetween(S->getCond(), S->getBody());
+    auto Gap = findGapAreaBetween(S->getRParenLoc(), getStart(S->getBody()));
     if (Gap)
       fillGapAreaWithCount(Gap->getBegin(), Gap->getEnd(), BodyCount);
 
     Counter OutCount =
         addCounters(BC.BreakCount, subtractCounters(CondCount, BodyCount));
     if (OutCount != ParentCount)
       pushRegion(OutCount);
 
Counter CondCount = addCounters(
         addCounters(ParentCount, BackedgeCount, BodyBC.ContinueCount),
         IncrementBC.ContinueCount);
     if (const Expr *Cond = S->getCond()) {
       propagateCounts(CondCount, Cond);
       adjustForOutOfOrderTraversal(getEnd(S));
     }
 
     // The body count applies to the area immediately after the increment.
-    auto Gap = findGapAreaBetween(getPreciseTokenLocEnd(S->getRParenLoc()),
-                                  getStart(S->getBody()));
+    auto Gap = findGapAreaBetween(S->getRParenLoc(), getStart(S->getBody()));
     if (Gap)
       fillGapAreaWithCount(Gap->getBegin(), Gap->getEnd(), BodyCount);
 
     Counter OutCount = addCounters(BodyBC.BreakCount, IncrementBC.BreakCount,
                                    subtractCounters(CondCount, BodyCount));
     if (OutCount != ParentCount)
       pushRegion(OutCount);
 
void VisitCXXForRangeStmt(const CXXForRangeStmt *S) {
     Counter BodyCount = getRegionCounter(S);
 
     BreakContinueStack.push_back(BreakContinue());
     extendRegion(S->getBody());
     Counter BackedgeCount = propagateCounts(BodyCount, S->getBody());
     BreakContinue BC = BreakContinueStack.pop_back_val();
 
     // The body count applies to the area immediately after the range.
-    auto Gap = findGapAreaBetween(getPreciseTokenLocEnd(S->getRParenLoc()),
-                                  getStart(S->getBody()));
+    auto Gap = findGapAreaBetween(S->getRParenLoc(), getStart(S->getBody()));
     if (Gap)
       fillGapAreaWithCount(Gap->getBegin(), Gap->getEnd(), BodyCount);
 
     Counter LoopCount =
         addCounters(ParentCount, BackedgeCount, BC.ContinueCount);
     Counter OutCount =
         addCounters(BC.BreakCount, subtractCounters(LoopCount, BodyCount));
     if (OutCount != ParentCount)
void VisitObjCForCollectionStmt(const ObjCForCollectionStmt *S) {
     Counter BodyCount = getRegionCounter(S);
 
     BreakContinueStack.push_back(BreakContinue());
     extendRegion(S->getBody());
     Counter BackedgeCount = propagateCounts(BodyCount, S->getBody());
     BreakContinue BC = BreakContinueStack.pop_back_val();
 
     // The body count applies to the area immediately after the collection.
-    auto Gap = findGapAreaBetween(getPreciseTokenLocEnd(S->getRParenLoc()),
-                                  getStart(S->getBody()));
+    auto Gap = findGapAreaBetween(S->getRParenLoc(), getStart(S->getBody()));
     if (Gap)
       fillGapAreaWithCount(Gap->getBegin(), Gap->getEnd(), BodyCount);
 
     Counter LoopCount =
         addCounters(ParentCount, BackedgeCount, BC.ContinueCount);
     Counter OutCount =
         addCounters(BC.BreakCount, subtractCounters(LoopCount, BodyCount));
     if (OutCount != ParentCount)
void VisitIfStmt(const IfStmt *S) {
     Counter ParentCount = getRegion().getCounter();
     Counter ThenCount = getRegionCounter(S);
 
     // Emitting a counter for the condition makes it easier to interpret the
     // counter for the body when looking at the coverage.
     propagateCounts(ParentCount, S->getCond());
 
     // The 'then' count applies to the area immediately after the condition.
-    auto Gap = findGapAreaBetween(S->getCond(), S->getThen());
+    auto Gap = findGapAreaBetween(S->getRParenLoc(), getStart(S->getThen()));
     if (Gap)
       fillGapAreaWithCount(Gap->getBegin(), Gap->getEnd(), ThenCount);
 
     extendRegion(S->getThen());
     Counter OutCount = propagateCounts(ThenCount, S->getThen());
 
     Counter ElseCount = subtractCounters(ParentCount, ThenCount);
     if (const Stmt *Else = S->getElse()) {
       // The 'else' count applies to the area immediately after the 'then'.
-      Gap = findGapAreaBetween(S->getThen(), Else);
+      Gap = findGapAreaBetween(getEnd(S->getThen()), getStart(Else));
       if (Gap)
         fillGapAreaWithCount(Gap->getBegin(), Gap->getEnd(), ElseCount);
       extendRegion(Else);
       OutCount = addCounters(OutCount, propagateCounts(ElseCount, Else));
     } else
       OutCount = addCounters(OutCount, ElseCount);
 
     if (OutCount != ParentCount)

clang/test/CoverageMapping/if.cpp

 // RUN: %clang_cc1 -mllvm -emptyline-comment-coverage=false -fprofile-instrument=clang -fcoverage-mapping -dump-coverage-mapping -emit-llvm-only -std=c++1z -triple %itanium_abi_triple -main-file-name if.cpp %s | FileCheck %s
 
 int nop() { return 0; }
 
 // CHECK-LABEL: _Z3foov:
                                 // CHECK-NEXT: [[@LINE+3]]:12 -> [[@LINE+8]]:2 = #0
                                 // CHECK-NEXT: [[@LINE+3]]:15 -> [[@LINE+3]]:19 = #0
                                 // CHECK-NEXT: Branch,File 0, [[@LINE+2]]:15 -> [[@LINE+2]]:19 = 0, 0
-void foo() {                    // CHECK-NEXT: Gap,File 0, [[@LINE+1]]:20 -> [[@LINE+1]]:22 = #2
+void foo() {                    // CHECK-NEXT: Gap,File 0, [[@LINE+1]]:21 -> [[@LINE+1]]:22 = #2
   if (int j = true ? nop()      // CHECK-NEXT: [[@LINE]]:22 -> [[@LINE]]:27 = #2
                    : nop();     // CHECK-NEXT: [[@LINE]]:22 -> [[@LINE]]:27 = (#0 - #2)
       j)                        // CHECK-NEXT: [[@LINE]]:7 -> [[@LINE]]:8 = #0
     ++j;                        // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:7 -> [[@LINE-1]]:8 = #1, (#0 - #1)
 }                               // CHECK-NEXT: [[@LINE-2]]:9 -> [[@LINE-1]]:5 = #1
                                 // CHECK-NEXT: [[@LINE-2]]:5 -> [[@LINE-2]]:8 = #1
 // CHECK-LABEL: main:
 int main() {                    // CHECK: File 0, [[@LINE]]:12 -> {{[0-9]+}}:2 = #0
   int i = 0;
int main() {                    // CHECK: File 0, [[@LINE]]:12 -> {{[0-9]+}}:2 = #0
   if(i != 0) {                  // CHECK-NEXT: Gap,File 0, [[@LINE]]:13 -> [[@LINE]]:14 = #4
     i = 1;                      // CHECK-NEXT: File 0, [[@LINE-1]]:14 -> [[@LINE+1]]:4 = #4
   } else {                      // CHECK-NEXT: Gap,File 0, [[@LINE]]:4 -> [[@LINE]]:10 = (#0 - #4)
     i = 3;                      // CHECK-NEXT: File 0, [[@LINE-1]]:10 -> [[@LINE+1]]:4 = (#0 - #4)
   }
 
                                 // CHECK-NEXT: File 0, [[@LINE+2]]:7 -> [[@LINE+2]]:13 = #0
                                 // CHECK-NEXT: Branch,File 0, [[@LINE+1]]:7 -> [[@LINE+1]]:13 = #5, (#0 - #5)
-  i = i == 0?                   // CHECK-NEXT: Gap,File 0, [[@LINE]]:13 -> [[@LINE+1]]:9 = #5
+  i = i == 0?                   // CHECK-NEXT: Gap,File 0, [[@LINE]]:14 -> [[@LINE+1]]:9 = #5
         i + 1 :                 // CHECK-NEXT: File 0, [[@LINE]]:9 -> [[@LINE]]:14 = #5
         i + 2;                  // CHECK-NEXT: File 0, [[@LINE]]:9 -> [[@LINE]]:14 = (#0 - #5)
 
-                                // CHECK-NEXT: File 0, [[@LINE+4]]:7 -> [[@LINE+4]]:13 = #0
-                                // CHECK-NEXT: Branch,File 0, [[@LINE+3]]:7 -> [[@LINE+3]]:13 = #6, (#0 - #6)
-                                // CHECK-NEXT: Gap,File 0, [[@LINE+2]]:13 -> [[@LINE+2]]:14 = #6
+                                // CHECK-NEXT: File 0, [[@LINE+3]]:7 -> [[@LINE+3]]:13 = #0
+                                // CHECK-NEXT: Branch,File 0, [[@LINE+2]]:7 -> [[@LINE+2]]:13 = #6, (#0 - #6)
                                 // CHECK-NEXT: File 0, [[@LINE+1]]:14 -> [[@LINE+1]]:20 = #6
   i = i == 0?i + 12:i + 10;     // CHECK-NEXT: File 0, [[@LINE]]:21 -> [[@LINE]]:27 = (#0 - #6)
 
   return 0;
 }
 
 #define FOO true
 
 // CHECK-LABEL: _Z7ternaryv:
 void ternary() {
   true ? FOO : FOO; // CHECK-NOT: Gap,{{.*}}, [[@LINE]]:8 ->
 }

clang/test/CoverageMapping/macro-expressions.cpp

 }
 
 void STMT(fn3)() {
 }
 
 // CHECK: foo
 // CHECK-NEXT: File 0, [[@LINE+1]]:17 -> {{[0-9]+}}:2 = #0
 void foo(int i) {
-  // CHECK-NEXT: File 0, [[@LINE+2]]:7 -> [[@LINE+2]]:8 = #0
-  // CHECK: File 0, [[@LINE+1]]:10 -> [[@LINE+1]]:12 = #1
+  // CHECK-NEXT: File 0, [[@LINE+3]]:7 -> [[@LINE+3]]:8 = #0
+  // CHECK: Gap,File 0, [[@LINE+2]]:9 -> [[@LINE+2]]:10 = #1
+  // CHECK-NEXT: File 0, [[@LINE+1]]:10 -> [[@LINE+1]]:12 = #1
   if (0) {}
 
-  // CHECK-NEXT: Expansion,File 0, [[@LINE+2]]:7 -> [[@LINE+2]]:11 = #0
+  // CHECK-NEXT: Expansion,File 0, [[@LINE+3]]:7 -> [[@LINE+3]]:11 = #0
+  // CHECK-NEXT: Gap,File 0, [[@LINE+2]]:15 -> [[@LINE+2]]:16 = #2
   // CHECK-NEXT: File 0, [[@LINE+1]]:16 -> [[@LINE+1]]:18 = #2
   if (EXPR(i)) {}
-  // CHECK-NEXT: Expansion,File 0, [[@LINE+2]]:9 -> [[@LINE+2]]:14 = (#0 + #3)
-  // CHECK: File 0, [[@LINE+1]]:20 -> [[@LINE+1]]:22 = #3
+  // CHECK-NEXT: Expansion,File 0, [[@LINE+3]]:9 -> [[@LINE+3]]:14 = (#0 + #3)
+  // CHECK-NEXT: Gap,File 0, [[@LINE+2]]:19 -> [[@LINE+2]]:20 = #3
+  // CHECK-NEXT: File 0, [[@LINE+1]]:20 -> [[@LINE+1]]:22 = #3
   for (;NEXPR(i);) {}
-  // CHECK-NEXT: Expansion,File 0, [[@LINE+4]]:8 -> [[@LINE+4]]:14 = #0
-  // CHECK-NEXT: Expansion,File 0, [[@LINE+3]]:33 -> [[@LINE+3]]:35 = (#0 + #4)
-  // CHECK-NEXT: Expansion,File 0, [[@LINE+2]]:43 -> [[@LINE+2]]:46 = #4
+  // CHECK-NEXT: Expansion,File 0, [[@LINE+5]]:8 -> [[@LINE+5]]:14 = #0
+  // CHECK-NEXT: Expansion,File 0, [[@LINE+4]]:33 -> [[@LINE+4]]:35 = (#0 + #4)
+  // CHECK-NEXT: Expansion,File 0, [[@LINE+3]]:43 -> [[@LINE+3]]:46 = #4
+  // CHECK-NEXT: Gap,File 0, [[@LINE+2]]:50 -> [[@LINE+2]]:51 = #4
   // CHECK: File 0, [[@LINE+1]]:51 -> [[@LINE+1]]:53 = #4
   for (ASSIGN(DECL(int, j), 0); LT(j, i); INC(j)) {}
   // CHECK-NEXT: Expansion,File 0, [[@LINE+1]]:3 -> [[@LINE+1]]:9 = #0
   ASSIGN(DECL(int, k), 0);
-  // CHECK-NEXT: Expansion,File 0, [[@LINE+3]]:10 -> [[@LINE+3]]:12 = (#0 + #5)
+  // CHECK-NEXT: Expansion,File 0, [[@LINE+4]]:10 -> [[@LINE+4]]:12 = (#0 + #5)
+  // CHECK-NEXT: Gap,File 0, [[@LINE+3]]:19 -> [[@LINE+3]]:20 = #5
   // CHECK-NEXT: File 0, [[@LINE+2]]:20 -> [[@LINE+2]]:31 = #5
   // CHECK-NEXT: Expansion,File 0, [[@LINE+1]]:22 -> [[@LINE+1]]:25 = #5
   while (LT(k, i)) { INC(k); }
   // CHECK-NEXT: File 0, [[@LINE+2]]:6 -> [[@LINE+2]]:8 = (#0 + #6)
   // CHECK-NEXT: Expansion,File 0, [[@LINE+1]]:16 -> [[@LINE+1]]:21 = (#0 + #6)
   do {} while (NEXPR(i));
-  // CHECK-NEXT: Expansion,File 0, [[@LINE+4]]:8 -> [[@LINE+4]]:12 = #0
-  // CHECK-NEXT: Branch,File 0, [[@LINE+3]]:21 -> [[@LINE+3]]:22 = #7, #0
-  // CHECK-NEXT: Expansion,File 0, [[@LINE+2]]:23 -> [[@LINE+2]]:26 = #0
+  // CHECK-NEXT: Expansion,File 0, [[@LINE+5]]:8 -> [[@LINE+5]]:12 = #0
+  // CHECK-NEXT: Branch,File 0, [[@LINE+4]]:21 -> [[@LINE+4]]:22 = #7, #0
+  // CHECK-NEXT: Expansion,File 0, [[@LINE+3]]:23 -> [[@LINE+3]]:26 = #0
+  // CHECK-NEXT: Gap,File 0, [[@LINE+2]]:41 -> [[@LINE+2]]:42 = #7
   // CHECK: File 0, [[@LINE+1]]:42 -> [[@LINE+1]]:44 = #7
   for (DECL(int, j) : ARR(int, 1, 2, 3)) {}
 
-  // CHECK-NEXT: File 0, [[@LINE+4]]:10 -> [[@LINE+4]]:11 = #0
-  // CHECK-NEXT: Branch,File 0, [[@LINE+3]]:10 -> [[@LINE+3]]:11 = #8, (#0 - #8)
+  // CHECK-NEXT: File 0, [[@LINE+5]]:10 -> [[@LINE+5]]:11 = #0
+  // CHECK-NEXT: Branch,File 0, [[@LINE+4]]:10 -> [[@LINE+4]]:11 = #8, (#0 - #8)
+  // CHECK-NEXT: Gap,File 0, [[@LINE+3]]:13 -> [[@LINE+3]]:14 = #8
   // CHECK-NEXT: Expansion,File 0, [[@LINE+2]]:14 -> [[@LINE+2]]:20 = #0
   // CHECK-NEXT: Expansion,File 0, [[@LINE+1]]:23 -> [[@LINE+1]]:29 = #0
   (void)(i ? PRIo64 : PRIu64);
 
   // CHECK-NEXT: File 0, [[@LINE+6]]:10 -> [[@LINE+6]]:11 = #0
   // CHECK: File 0, [[@LINE+5]]:14 -> [[@LINE+5]]:15 = #9
   // CHECK-NEXT: File 0, [[@LINE+4]]:18 -> [[@LINE+4]]:33 = (#0 - #9)
   // CHECK-NEXT: Expansion,File 0, [[@LINE+3]]:18 -> [[@LINE+3]]:22 = (#0 - #9)

clang/test/CoverageMapping/macroparams2.c

 // RUN: %clang_cc1 -mllvm -emptyline-comment-coverage=false -fprofile-instrument=clang -fcoverage-mapping -dump-coverage-mapping -emit-llvm-only -main-file-name macroparams2.c %s | FileCheck %s
 
 #define MACRO(REFS, CALLS)  (4 * (CALLS) < (REFS))
 
 struct S {
   int i, j;
 };
 
-// CHECK: File 0, [[@LINE+1]]:12 -> [[@LINE+10]]:2 = #0
+// CHECK: File 0, [[@LINE+1]]:12 -> [[@LINE+11]]:2 = #0
 int main() {
   struct S arr[32] = { 0 };
   int n = 0;
-  // CHECK-NEXT: Expansion,File 0, [[@LINE+2]]:7 -> [[@LINE+2]]:12 = #0
+  // CHECK-NEXT: Expansion,File 0, [[@LINE+3]]:7 -> [[@LINE+3]]:12 = #0
+  // CHECK-NEXT: Gap,File 0, [[@LINE+2]]:33 -> [[@LINE+2]]:34 = #1
   // CHECK-NEXT: File 0, [[@LINE+1]]:34 -> [[@LINE+3]]:4 = #1
   if (MACRO(arr[n].j, arr[n].i)) {
     n = 1;
   }
   return n;
 }
 
 // CHECK: File 1, 3:29 -> 3:51 = #0

clang/test/CoverageMapping/macros.c

 void func3() { // CHECK-NEXT: File 0, [[@LINE]]:14 -> [[@LINE+3]]:2 = #0
   MACRO_2; // CHECK-NEXT: Expansion,File 0, [[@LINE]]:3 -> [[@LINE]]:10 = #0
   MACRO_2; // CHECK-NEXT: Expansion,File 0, [[@LINE]]:3 -> [[@LINE]]:10 = #0
 }
 // CHECK-NEXT: File 1, 4:17 -> 4:22 = #0
 // CHECK-NEXT: File 2, 4:17 -> 4:22 = #0
 
 // CHECK-NEXT: func4
-void func4() { // CHECK-NEXT: File 0, [[@LINE]]:14 -> [[@LINE+7]]:2 = #0
+void func4() { // CHECK-NEXT: File 0, [[@LINE]]:14 -> [[@LINE+8]]:2 = #0
   int i = 0;
   while (i++ < 10) // CHECK-NEXT: File 0, [[@LINE]]:10 -> [[@LINE]]:18 = (#0 + #1)
-    if (i < 5) // CHECK: File 0, [[@LINE]]:5 -> [[@LINE+3]]:14 = #1
+    if (i < 5) // CHECK: File 0, [[@LINE]]:5 -> [[@LINE+4]]:14 = #1
                // CHECK-NEXT: File 0, [[@LINE-1]]:9 -> [[@LINE-1]]:14 = #1
                // CHECK-NEXT: Branch,File 0, [[@LINE-2]]:9 -> [[@LINE-2]]:14 = #2, (#1 - #2)
+               // CHECK-NEXT: Gap,File 0, [[@LINE-3]]:15 -> [[@LINE+1]]:7 = #2
       MACRO_2; // CHECK-NEXT: Expansion,File 0, [[@LINE]]:7 -> [[@LINE]]:14 = #2
 }
 // CHECK-NEXT: File 1, 4:17 -> 4:22 = #2
 // CHECK-NOT: File 1
 
 // CHECK-NEXT: func5
-void func5() { // CHECK-NEXT: File 0, [[@LINE]]:14 -> [[@LINE+5]]:2 = #0
+void func5() { // CHECK-NEXT: File 0, [[@LINE]]:14 -> [[@LINE+6]]:2 = #0
   int i = 0;
   if (i > 5) // CHECK-NEXT: File 0, [[@LINE]]:7 -> [[@LINE]]:12 = #0
              // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:7 -> [[@LINE-1]]:12 = #1, (#0 - #1)
+             // CHECK-NEXT: Gap,File 0, [[@LINE-2]]:13 -> [[@LINE+1]]:5 = #1
     MACRO_3; // CHECK-NEXT: Expansion,File 0, [[@LINE]]:5 -> [[@LINE]]:12 = #1
 }
 // CHECK-NEXT: Expansion,File 1, 6:17 -> 6:24 = #1
 // CHECK-NEXT: File 2, 4:17 -> 4:22 = #1
 
 // CHECK-NEXT: func6
-void func6(unsigned count) { // CHECK-NEXT: File 0, [[@LINE]]:28 -> [[@LINE+5]]:2 = #0
-begin:                       // CHECK-NEXT: File 0, [[@LINE]]:1 -> [[@LINE+4]]:2 = #1
+void func6(unsigned count) { // CHECK-NEXT: File 0, [[@LINE]]:28 -> [[@LINE+6]]:2 = #0
+begin:                       // CHECK-NEXT: File 0, [[@LINE]]:1 -> [[@LINE+5]]:2 = #1
     if (count--)             // CHECK-NEXT: File 0, [[@LINE]]:9 -> [[@LINE]]:16 = #1
                              // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:9 -> [[@LINE-1]]:16 = #2, (#1 - #2)
+                             // CHECK-NEXT: Gap,File 0, [[@LINE-2]]:17 -> [[@LINE+1]]:9 = #2
         GOTO begin;          // CHECK-NEXT: File 0, [[@LINE]]:9 -> [[@LINE]]:19 = #2
 }
 // CHECK-NEXT: Expansion,File 0, [[@LINE-2]]:9 -> [[@LINE-2]]:13 = #2
 // CHECK-NEXT: File 1, 7:14 -> 7:18 = #2
 
+// Regression test for gap region between macros.
+// CHECK-NEXT: func7
+int k, l;
+#define m(e) e##e
+void func7() { // CHECK-NEXT: File 0, [[@LINE]]:14 -> [[@LINE+6]]:2 = #0
+  int kk,ll;   // CHECK-NEXT: File 0, [[@LINE+1]]:7 -> [[@LINE+1]]:8 = #0
+  if (k)       // CHECK-NEXT: Branch,File 0, [[@LINE]]:7 -> [[@LINE]]:8 = #1
+    m(k);      // CHECK-NEXT: Gap,File 0, [[@LINE-1]]:9 -> [[@LINE]]:5 = #1
+  else         // CHECK-NEXT: Expansion,File 0, [[@LINE-1]]:5 -> [[@LINE-1]]:6 = #0
+    l = m(l);  // CHECK-NEXT: Gap,File 0, [[@LINE-2]]:7 -> [[@LINE]]:5 = (#0 - #1)
+}              // CHECK-NEXT: File 0, [[@LINE-1]]:5 -> [[@LINE-1]]:10 = (#0 - #1)
+               // CHECK-NEXT: Expansion,File 0, [[@LINE-2]]:9 -> [[@LINE-2]]:10 = (#0 - #1)
+               // CHECK-NEXT: File 1, [[@LINE-9]]:14 -> [[@LINE-9]]:18 = #0
+               // CHECK-NEXT: File 2, [[@LINE-10]]:14 -> [[@LINE-10]]:15 = (#0 - #1)
+
 int main(int argc, const char *argv[]) {
   func();
   func2();
   func3();
   func4();
 }

clang/test/CoverageMapping/macroscopes.cpp

int main() {
   ends_a_scope
 
   // CHECK-NEXT: Expansion,File 0, [[@LINE+3]]:3 -> [[@LINE+3]]:17 = #0
   // CHECK-NEXT: File 0, [[@LINE+2]]:17 -> [[@LINE+3]]:15 = #7
   // CHECK-NEXT: Expansion,File 0, [[@LINE+2]]:3 -> [[@LINE+2]]:15 = #7
   starts_a_scope
   ends_a_scope
 
-  // CHECK-NEXT: Expansion,File 0, [[@LINE+2]]:3 -> [[@LINE+2]]:17 = #0
+  // CHECK-NEXT: Expansion,File 0, [[@LINE+3]]:3 -> [[@LINE+3]]:17 = #0
+  // CHECK-NEXT: Gap,File 0, [[@LINE+2]]:17 -> [[@LINE+3]]:5 = #8
   // CHECK-NEXT: Expansion,File 0, [[@LINE+2]]:5 -> [[@LINE+2]]:16 = #8
   starts_a_while
     simple_stmt;
 
   x = 0;
-  // CHECK-NEXT: Expansion,File 0, [[@LINE+4]]:3 -> [[@LINE+4]]:17 = #0
+  // CHECK-NEXT: Expansion,File 0, [[@LINE+5]]:3 -> [[@LINE+5]]:17 = #0
+  // CHECK-NEXT: Gap,File 0, [[@LINE+4]]:17 -> [[@LINE+4]]:18 = #9
   // CHECK-NEXT: File 0, [[@LINE+3]]:18 -> [[@LINE+5]]:15 = #9
   // CHECK-NEXT: Expansion,File 0, [[@LINE+3]]:5 -> [[@LINE+3]]:16 = #9
   // CHECK-NEXT: Expansion,File 0, [[@LINE+3]]:3 -> [[@LINE+3]]:15 = #9
   starts_a_while {
     simple_stmt;
   ends_a_scope
 
   // CHECK-NEXT: Expansion,File 0, [[@LINE+1]]:3 -> [[@LINE+1]]:17 = #0

clang/test/CoverageMapping/moremacros.c

 // RUN: %clang_cc1 -mllvm -emptyline-comment-coverage=false -fprofile-instrument=clang -fcoverage-mapping -dump-coverage-mapping -emit-llvm-only -main-file-name macro-expansion.c %s | FileCheck %s
 
 #define LBRAC {
 #define RBRAC }
 
 // CHECK: main:
 // CHECK-NEXT: File 0, [[@LINE+1]]:40 -> {{[0-9]+}}:2 = #0
 int main(int argc, const char *argv[]) {
   // CHECK-NEXT: File 0, [[@LINE+1]]:7 -> [[@LINE+1]]:12 = #0
   if (!argc) {} // CHECK: File 0, [[@LINE]]:14 -> [[@LINE]]:16 = #1
 
-  // CHECK-NEXT: File 0, [[@LINE+4]]:7 -> [[@LINE+4]]:12 = #0
-  // CHECK-NEXT: Branch,File 0, [[@LINE+3]]:7 -> [[@LINE+3]]:12 = #2, (#0 - #2)
+  // CHECK-NEXT: File 0, [[@LINE+5]]:7 -> [[@LINE+5]]:12 = #0
+  // CHECK-NEXT: Branch,File 0, [[@LINE+4]]:7 -> [[@LINE+4]]:12 = #2, (#0 - #2)
+  // CHECK-NEXT: Gap,File 0, [[@LINE+3]]:13 -> [[@LINE+3]]:14 = #2
   // CHECK-NEXT: Expansion,File 0, [[@LINE+2]]:14 -> [[@LINE+2]]:19 = #2
   // CHECK-NEXT: File 0, [[@LINE+1]]:19 -> [[@LINE+4]]:8 = #2
   if (!argc) LBRAC
     return 0;
   // CHECK-NEXT: Expansion,File 0, [[@LINE+1]]:3 -> [[@LINE+1]]:8 = #2
-  RBRAC // CHECK-NEXT: [[@LINE]]:8 -> [[@LINE+7]]:3 = (#0 - #2)
+  RBRAC // CHECK-NEXT: [[@LINE]]:8 -> [[@LINE+8]]:3 = (#0 - #2)
 
-  // CHECK-NEXT: File 0, [[@LINE+5]]:3 -> [[@LINE+16]]:2 = (#0 - #2)
-  // CHECK-NEXT: File 0, [[@LINE+4]]:7 -> [[@LINE+4]]:12 = (#0 - #2)
-  // CHECK-NEXT: Branch,File 0, [[@LINE+3]]:7 -> [[@LINE+3]]:12 = #3, ((#0 - #2) - #3)
+  // CHECK-NEXT: File 0, [[@LINE+6]]:3 -> [[@LINE+17]]:2 = (#0 - #2)
+  // CHECK-NEXT: File 0, [[@LINE+5]]:7 -> [[@LINE+5]]:12 = (#0 - #2)
+  // CHECK-NEXT: Branch,File 0, [[@LINE+4]]:7 -> [[@LINE+4]]:12 = #3, ((#0 - #2) - #3)
+  // CHECK-NEXT: Gap,File 0, [[@LINE+3]]:13 -> [[@LINE+3]]:14 = #3
   // CHECK-NEXT: Expansion,File 0, [[@LINE+2]]:14 -> [[@LINE+2]]:19 = #3
   // CHECK-NEXT: File 0, [[@LINE+1]]:19 -> [[@LINE+3]]:4 = #3
   if (!argc) LBRAC
     return 0;
   } // CHECK-NEXT: [[@LINE]]:4 -> [[@LINE+5]]:3 = ((#0 - #2) - #3)
 
   // CHECK-NEXT: File 0, [[@LINE+3]]:3 -> [[@LINE+7]]:2 = ((#0 - #2) - #3)
   // CHECK-NEXT: File 0, [[@LINE+2]]:7 -> [[@LINE+2]]:12 = ((#0 - #2) - #3)