[clang] ef95590 - [Coverage] Resurrect Branch:FalseCnt in SwitchStmt that was pruned in #112694 (#120418)

via cfe-commits cfe-commits at lists.llvm.org
Wed Dec 18 15:41:11 PST 2024


Author: NAKAMURA Takumi
Date: 2024-12-19T08:41:07+09:00
New Revision: ef955908302b6a6170e9775d89a94846fde12ebf

URL: https://github.com/llvm/llvm-project/commit/ef955908302b6a6170e9775d89a94846fde12ebf
DIFF: https://github.com/llvm/llvm-project/commit/ef955908302b6a6170e9775d89a94846fde12ebf.diff

LOG: [Coverage] Resurrect Branch:FalseCnt in SwitchStmt that was pruned in #112694 (#120418)

I missed that FalseCnt for each Case was used to calculate percentage in
the SwitchStmt. At the moment I resurrect them.

In `!HasDefaultCase`, the pair of Counters shall be `[CaseCountSum,
FalseCnt]`. (Reversal of before #112694)
I think it can be considered as the False count on SwitchStmt.

FalseCnt shall be folded (same as current impl) in the coming
SingleByteCoverage changes, since percentage would not make sense.

Added: 
    

Modified: 
    clang/lib/CodeGen/CoverageMappingGen.cpp
    clang/test/CoverageMapping/switch.cpp
    clang/test/CoverageMapping/switchmacro.c

Removed: 
    


################################################################################
diff  --git a/clang/lib/CodeGen/CoverageMappingGen.cpp b/clang/lib/CodeGen/CoverageMappingGen.cpp
index 7248abe480cba8..cda218eac34af8 100644
--- a/clang/lib/CodeGen/CoverageMappingGen.cpp
+++ b/clang/lib/CodeGen/CoverageMappingGen.cpp
@@ -1146,12 +1146,15 @@ struct CounterCoverageMappingBuilder
 
   /// Create a Branch Region around a SwitchCase for code coverage
   /// and add it to the function's SourceRegions.
-  void createSwitchCaseRegion(const SwitchCase *SC, Counter TrueCnt) {
+  /// Returns Counter that corresponds to SC.
+  Counter createSwitchCaseRegion(const SwitchCase *SC, Counter ParentCount) {
     // Push region onto RegionStack but immediately pop it (which adds it to
     // the function's SourceRegions) because it doesn't apply to any other
     // source other than the SwitchCase.
+    Counter TrueCnt = getRegionCounter(SC);
     popRegions(pushRegion(TrueCnt, getStart(SC), SC->getColonLoc(),
-                          Counter::getZero()));
+                          subtractCounters(ParentCount, TrueCnt)));
+    return TrueCnt;
   }
 
   /// Check whether a region with bounds \c StartLoc and \c EndLoc
@@ -1863,16 +1866,22 @@ struct CounterCoverageMappingBuilder
     const SwitchCase *Case = S->getSwitchCaseList();
     for (; Case; Case = Case->getNextSwitchCase()) {
       HasDefaultCase = HasDefaultCase || isa<DefaultStmt>(Case);
-      auto CaseCount = getRegionCounter(Case);
+      auto CaseCount = createSwitchCaseRegion(Case, ParentCount);
       CaseCountSum = addCounters(CaseCountSum, CaseCount, /*Simplify=*/false);
-      createSwitchCaseRegion(Case, CaseCount);
     }
     // If no explicit default case exists, create a branch region to represent
     // the hidden branch, which will be added later by the CodeGen. This region
     // will be associated with the switch statement's condition.
     if (!HasDefaultCase) {
-      Counter DefaultCount = subtractCounters(ParentCount, CaseCountSum);
-      createBranchRegion(S->getCond(), Counter::getZero(), DefaultCount);
+      // Simplify is skipped while building the counters above: it can get
+      // really slow on top of switches with thousands of cases. Instead,
+      // trigger simplification by adding zero to the last counter.
+      CaseCountSum =
+          addCounters(CaseCountSum, Counter::getZero(), /*Simplify=*/true);
+
+      // This is considered as the False count on SwitchStmt.
+      Counter SwitchFalse = subtractCounters(ParentCount, CaseCountSum);
+      createBranchRegion(S->getCond(), CaseCountSum, SwitchFalse);
     }
   }
 

diff  --git a/clang/test/CoverageMapping/switch.cpp b/clang/test/CoverageMapping/switch.cpp
index a1fee644faaf0e..db4cddbc6b9415 100644
--- a/clang/test/CoverageMapping/switch.cpp
+++ b/clang/test/CoverageMapping/switch.cpp
@@ -2,13 +2,13 @@
 
 // CHECK: foo
 void foo(int i) {   // CHECK-NEXT: File 0, [[@LINE]]:17 -> [[@LINE+11]]:2 = #0
-  switch(i) {       // CHECK-NEXT: Branch,File 0, [[@LINE]]:10 -> [[@LINE]]:11 = 0, ((#0 - #2) - #3)
+  switch(i) {       // CHECK-NEXT: Branch,File 0, [[@LINE]]:10 -> [[@LINE]]:11 = (#2 + #3), ((#0 - #2) - #3)
                     // CHECK-NEXT: Gap,File 0, [[@LINE-1]]:13 -> [[@LINE+5]]:10 = 0
   case 1:           // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+1]]:11 = #2
-    return;         // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #2, 0
+    return;         // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #2, (#0 - #2)
                     // CHECK-NEXT: Gap,File 0, [[@LINE-1]]:12 -> [[@LINE+1]]:3 = 0
   case 2:           // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+1]]:10 = #3
-    break;          // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #3, 0
+    break;          // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #3, (#0 - #3)
 
   }                 // CHECK-NEXT: Gap,File 0, [[@LINE]]:4 -> [[@LINE+1]]:3 = #1
   int x = 0;        // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+1]]:2 = #1
@@ -28,14 +28,14 @@ void bar(int i) {   // CHECK-NEXT: File 0, [[@LINE]]:17 -> [[@LINE+21]]:2 = #0
     nop();          // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:11 -> [[@LINE-1]]:12 = 0, #2
                     // CHECK-NEXT: File 0, [[@LINE-1]]:5 -> [[@LINE-1]]:10 = 0
   switch (i)        // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+11]]:2 = #3
-  case 1:           // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:11 -> [[@LINE-1]]:12 = 0, (#3 - #5)
+  case 1:           // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:11 -> [[@LINE-1]]:12 = #5, (#3 - #5)
                     // CHECK-NEXT: File 0, [[@LINE-1]]:3 -> [[@LINE+1]]:10 = #5
-    nop();          // CHECK-NEXT: Branch,File 0, [[@LINE-2]]:3 -> [[@LINE-2]]:9 = #5, 0
+    nop();          // CHECK-NEXT: Branch,File 0, [[@LINE-2]]:3 -> [[@LINE-2]]:9 = #5, (#3 - #5)
                     // CHECK-NEXT: File 0, [[@LINE+1]]:3 -> [[@LINE+7]]:2 = #4
-  switch (i) {      // CHECK-NEXT: Branch,File 0, [[@LINE]]:11 -> [[@LINE]]:12 = 0, (#4 - #7)
+  switch (i) {      // CHECK-NEXT: Branch,File 0, [[@LINE]]:11 -> [[@LINE]]:12 = #7, (#4 - #7)
     nop();          // CHECK-NEXT: Gap,File 0, [[@LINE-1]]:14 -> [[@LINE+2]]:10 = 0
   case 1:           // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+1]]:10 = #7
-    nop();          // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #7, 0
+    nop();          // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #7, (#4 - #7)
   }
   nop();            // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+1]]:2 = #6
 }
@@ -53,35 +53,35 @@ int main() {        // CHECK-NEXT: File 0, [[@LINE]]:12 -> [[@LINE+39]]:2 = #0
   int i = 0;
   switch(i) {       // CHECK-NEXT: Gap,File 0, [[@LINE]]:13 -> [[@LINE+8]]:10 = 0
   case 0:           // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+2]]:10 = #2
-    i = 1;          // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #2, 0
+    i = 1;          // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #2, (#0 - #2)
     break;          // CHECK-NEXT: Gap,File 0, [[@LINE]]:11 -> [[@LINE+1]]:3 = 0
   case 1:           // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+2]]:10 = #3
-    i = 2;          // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #3, 0
+    i = 2;          // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #3, (#0 - #3)
     break;          // CHECK-NEXT: Gap,File 0, [[@LINE]]:11 -> [[@LINE+1]]:3 = 0
   default:          // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+1]]:10 = #4
-    break;          // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:10 = #4, 0
+    break;          // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:10 = #4, (#0 - #4)
   }                 // CHECK-NEXT: Gap,File 0, [[@LINE]]:4 -> [[@LINE+1]]:3 = #1
   switch(i) {       // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+27]]:2 = #1
   case 0:           // CHECK-NEXT: Gap,File 0, [[@LINE-1]]:13 -> [[@LINE+7]]:10 = 0
     i = 1;          // CHECK-NEXT: File 0, [[@LINE-1]]:3 -> [[@LINE+1]]:10 = #6
-    break;          // CHECK-NEXT: Branch,File 0, [[@LINE-2]]:3 -> [[@LINE-2]]:9 = #6, 0
+    break;          // CHECK-NEXT: Branch,File 0, [[@LINE-2]]:3 -> [[@LINE-2]]:9 = #6, (#1 - #6)
                     // CHECK-NEXT: Gap,File 0, [[@LINE-1]]:11 -> [[@LINE+1]]:3 = 0
   case 1:           // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+3]]:10 = #7
-    i = 2;          // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #7, 0
+    i = 2;          // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #7, (#1 - #7)
   default:          // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+1]]:10 = (#7 + #8)
-    break;          // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:10 = #8, 0
+    break;          // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:10 = #8, (#1 - #8)
   }                 // CHECK-NEXT: Gap,File 0, [[@LINE]]:4 -> [[@LINE+2]]:3 = #5
                     // CHECK-NEXT: File 0, [[@LINE+1]]:3 -> [[@LINE+17]]:2 = #5
-  switch(i) {       // CHECK-NEXT: Branch,File 0, [[@LINE]]:10 -> [[@LINE]]:11 = 0, ((((#5 - #10) - #11) - #12) - #13)
+  switch(i) {       // CHECK-NEXT: Branch,File 0, [[@LINE]]:10 -> [[@LINE]]:11 = (((#10 + #11) + #12) + #13), ((((#5 - #10) - #11) - #12) - #13)
                     // CHECK-NEXT: Gap,File 0, [[@LINE-1]]:13 -> [[@LINE+8]]:11 = 0
   case 1:           // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+7]]:11 = #10
-                    // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #10, 0
+                    // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #10, (#5 - #10)
   case 2:           // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+5]]:11 = (#10 + #11)
-    i = 11;         // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #11, 0
+    i = 11;         // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #11, (#5 - #11)
   case 3:           // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+3]]:11 = ((#10 + #11) + #12)
-                    // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #12, 0
+                    // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #12, (#5 - #12)
   case 4:           // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+1]]:11 = (((#10 + #11) + #12) + #13)
-    i = 99;         // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #13, 0
+    i = 99;         // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #13, (#5 - #13)
   }
 
   foo(1);           // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+3]]:11 = #9
@@ -95,10 +95,10 @@ int pr44011(int i) { // CHECK-NEXT: File 0, [[@LINE]]:20 -> {{.*}}:2 = #0
   switch (i) {       // CHECK-NEXT: Gap,File 0, [[@LINE]]:14 -> [[@LINE+6]]:13 = 0
 
   case 1:            // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+1]]:13 = #2
-    return 0;        // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #2, 0
+    return 0;        // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #2, (#0 - #2)
                      // CHECK-NEXT: Gap,File 0, [[@LINE-1]]:14 -> [[@LINE+1]]:3 = 0
   default:           // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+1]]:13 = #3
-    return 1;        // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:10 = #3, 0
+    return 1;        // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:10 = #3, (#0 - #3)
   }
 } // A region for counter #1 is missing due to the missing return.
 
@@ -106,17 +106,17 @@ int pr44011(int i) { // CHECK-NEXT: File 0, [[@LINE]]:20 -> {{.*}}:2 = #0
 // FIXME: End location for "case 1" shouldn't point at the end of the switch.
                          // CHECK: fallthrough
 int fallthrough(int i) { // CHECK-NEXT: File 0, [[@LINE]]:24 -> [[@LINE+14]]:2 = #0
-                    // CHECK-NEXT: Branch,File 0, [[@LINE+1]]:10 -> [[@LINE+1]]:11 = 0, ((((#0 - #2) - #3) - #4) - #5)
+                    // CHECK-NEXT: Branch,File 0, [[@LINE+1]]:10 -> [[@LINE+1]]:11 = (((#2 + #3) + #4) + #5), ((((#0 - #2) - #3) - #4) - #5)
   switch(i) {       // CHECK-NEXT: Gap,File 0, [[@LINE]]:13 -> [[@LINE+10]]:10 = 0
   case 1:           // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+9]]:10 = #2
-    i = 23;         // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #2, 0
+    i = 23;         // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #2, (#0 - #2)
   case 2:           // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+2]]:10 = (#2 + #3)
-    i = 11;         // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #3, 0
+    i = 11;         // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #3, (#0 - #3)
     break;          // CHECK-NEXT: Gap,File 0, [[@LINE]]:11 -> [[@LINE+1]]:3 = 0
   case 3:           // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+4]]:10 = #4
-                    // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #4, 0
+                    // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #4, (#0 - #4)
   case 4:           // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+2]]:10 = (#4 + #5)
-    i = 99;         // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #5, 0
+    i = 99;         // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #5, (#0 - #5)
     break;
   }
 }
@@ -126,12 +126,12 @@ void abort(void) __attribute((noreturn));
 int noret(int x) { // CHECK-NEXT: File 0, [[@LINE]]:18 -> [[@LINE+11]]:2
   switch (x) {     // CHECK-NEXT: Gap,File 0, [[@LINE]]:14 -> [[@LINE+8]]:14 = 0
   default:         // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+1]]:12
-    abort();      // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:10 = #2, 0
+    abort();      // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:10 = #2, (#0 - #2)
                   // CHECK-NEXT: Gap,File 0, [[@LINE-1]]:13 -> [[@LINE+1]]:3 = 0
   case 1:         // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+1]]:13
-    return 5;     // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #3, 0
+    return 5;     // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #3, (#0 - #3)
                   // CHECK-NEXT: Gap,File 0, [[@LINE-1]]:14 -> [[@LINE+1]]:3 = 0
   case 2:         // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+1]]:14
-    return 10;    // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #4, 0
+    return 10;    // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #4, (#0 - #4)
   }
 }

diff  --git a/clang/test/CoverageMapping/switchmacro.c b/clang/test/CoverageMapping/switchmacro.c
index 0696e7490cdf99..4c98cc7d9403a4 100644
--- a/clang/test/CoverageMapping/switchmacro.c
+++ b/clang/test/CoverageMapping/switchmacro.c
@@ -6,7 +6,7 @@
 int foo(int i) { // CHECK-NEXT: File 0, [[@LINE]]:16 -> {{[0-9]+}}:2 = #0
   switch (i) {   // CHECK-NEXT: Gap,File 0, [[@LINE]]:14 -> {{[0-9]+}}:11 = 0
   default:       // CHECK-NEXT: File 0, [[@LINE]]:3 -> {{[0-9]+}}:11 = #2
-                 // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:10 = #2, 0
+                 // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:10 = #2, (#0 - #2)
     if (i == 1)  // CHECK-NEXT: File 0, [[@LINE]]:9 -> [[@LINE]]:15 = #2
                  // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:9 -> [[@LINE-1]]:15 = #3, (#2 - #3)
       return 0;  // CHECK: File 0, [[@LINE]]:7 -> [[@LINE]]:15 = #3
@@ -15,7 +15,7 @@ int foo(int i) { // CHECK-NEXT: File 0, [[@LINE]]:16 -> {{[0-9]+}}:2 = #0
     // CHECK-NEXT: File 0, [[@LINE+1]]:8 -> {{[0-9]+}}:11 = (#2 - #3)
     FOO(1);
   case 0:        // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+2]]:13 = ((#2 + #4) - #3)
-                 // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #4, 0
+                 // CHECK-NEXT: Branch,File 0, [[@LINE-1]]:3 -> [[@LINE-1]]:9 = #4, (#0 - #4)
     return 2;    // CHECK-NEXT: Gap,File 0, [[@LINE]]:14 -> [[@LINE+4]]:3 = 0
 
   // CHECK-NEXT: Expansion,File 0, [[@LINE+2]]:3 -> [[@LINE+2]]:6 = 0


        


More information about the cfe-commits mailing list