[Coverage][Expansion] handle nested macros in scratch space

Author: whentojump

clang/lib/CodeGen/CoverageMappingGen.cpp

@@ -298,6 +298,22 @@ class CoverageMappingBuilder {
                            : SM.getIncludeLoc(SM.getFileID(Loc));
   }
 
+  /// Find out where the current file is included or macro is expanded. If the
+  /// found expansion is a <scratch space>, keep looking.
+  SourceLocation getIncludeOrNonScratchExpansionLoc(SourceLocation Loc) {
+    if (Loc.isMacroID()) {
+      Loc = SM.getImmediateExpansionRange(Loc).getBegin();
+      while (Loc.isMacroID() &&
+             SM.isWrittenInScratchSpace(SM.getSpellingLoc(Loc))) {
+        auto ExpansionRange = SM.getImmediateExpansionRange(Loc);
+        Loc = ExpansionRange.getBegin();
+      }
+    } else {
+      Loc = SM.getIncludeLoc(SM.getFileID(Loc));
+    }
+    return Loc;
+  }
+
   /// Return true if \c Loc is a location in a built-in macro.
   bool isInBuiltin(SourceLocation Loc) {
     return SM.getBufferName(SM.getSpellingLoc(Loc)) == "<built-in>";
@@ -527,7 +543,8 @@ class CoverageMappingBuilder {
     SourceRegionFilter Filter;
     for (const auto &FM : FileIDMapping) {
       SourceLocation ExpandedLoc = FM.second.second;
-      SourceLocation ParentLoc = getIncludeOrExpansionLoc(ExpandedLoc);
+      SourceLocation ParentLoc =
+          getIncludeOrNonScratchExpansionLoc(ExpandedLoc);
       if (ParentLoc.isInvalid())
         continue;
 

clang/test/CoverageMapping/mcdc-scratch-space.c

@@ -26,6 +26,19 @@ int pre0(int pre_a, int b_post) {
   // CHECK: Branch,File 1, [[@LINE-9]]:16 -> [[@LINE-9]]:22 = #1, (#0 - #1) [1,2,0]
 }
 
+#define pre_foo pre_a
+
+// CHECK: pre1:
+int pre1(int pre_a, int b_post) {
+  // CHECK: Decision,File 0, [[@LINE+3]]:11 -> [[@LINE+4]]:20 = M:0, C:2
+  // CHECK: Expansion,File 0, [[@LINE+2]]:11 -> [[@LINE+2]]:14 = #0 (Expanded file = 1)
+  // CHECK: Branch,File 0, [[@LINE+2]]:14 -> [[@LINE+2]]:20 = #2, (#1 - #2) [2,0,0]
+  return (PRE(foo)
+          && b_post);
+  // CHECK: Expansion,File 1, 17:16 -> 17:20 = #0 (Expanded file = 2)
+  // CHECK: Branch,File 2, 29:17 -> 29:22 = #1, (#0 - #1) [1,2,0]
+}
+
 #define POST(x) x##_post
 
 // CHECK: post0:
@@ -37,3 +50,16 @@ int post0(int pre_a, int b_post) {
   // CHECK: Expansion,File 0, [[@LINE-1]]:14 -> [[@LINE-1]]:18 = #1 (Expanded file = 1)
   // CHECK: Branch,File 1, [[@LINE-9]]:17 -> [[@LINE-9]]:20 = (#1 - #2), #2 [2,0,0]
 }
+
+#define bar_post b_post
+
+// CHECK: post1:
+int post1(int pre_a, int b_post) {
+  // CHECK: Decision,File 0, [[@LINE+3]]:11 -> [[@LINE+4]]:18 = M:0, C:2
+  // CHECK: Branch,File 0, [[@LINE+2]]:11 -> [[@LINE+2]]:16 = (#0 - #1), #1 [1,0,2]
+  // CHECK: Expansion,File 0, [[@LINE+2]]:14 -> [[@LINE+2]]:18 = 0 (Expanded file = 1)
+  return (pre_a
+          || POST(bar));
+  // CHECK: Expansion,File 1, 42:17 -> 42:18 = #1 (Expanded file = 2)
+  // CHECK: Branch,File 2, 54:18 -> 54:24 = (#1 - #2), #2 [2,0,0]
+}