Author: efriedma Date: Wed Aug 2 16:22:50 2017 New Revision: 309901 URL: http://llvm.org/viewvc/llvm-project?rev=309901&view=rev Log: [coverage] Make smaller regions for the first case of a switch.
We never overwrite the end location of a region, so we would end up with an overly large region when we reused the switch's region. It's possible this code will be substantially rewritten in the near future to deal with fallthrough more accurately, but this seems like an improvement on its own for now. Differential Revision: https://reviews.llvm.org/D34801 Modified: cfe/trunk/lib/CodeGen/CoverageMappingGen.cpp cfe/trunk/test/CoverageMapping/switch.cpp Modified: cfe/trunk/lib/CodeGen/CoverageMappingGen.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CoverageMappingGen.cpp?rev=309901&r1=309900&r2=309901&view=diff ============================================================================== --- cfe/trunk/lib/CodeGen/CoverageMappingGen.cpp (original) +++ cfe/trunk/lib/CodeGen/CoverageMappingGen.cpp Wed Aug 2 16:22:50 2017 @@ -704,6 +704,8 @@ struct CounterCoverageMappingBuilder assert(!BreakContinueStack.empty() && "break not in a loop or switch!"); BreakContinueStack.back().BreakCount = addCounters( BreakContinueStack.back().BreakCount, getRegion().getCounter()); + // FIXME: a break in a switch should terminate regions for all preceding + // case statements, not just the most recent one. terminateRegion(S); } @@ -845,15 +847,20 @@ struct CounterCoverageMappingBuilder extendRegion(Body); if (const auto *CS = dyn_cast<CompoundStmt>(Body)) { if (!CS->body_empty()) { - // The body of the switch needs a zero region so that fallthrough counts - // behave correctly, but it would be misleading to include the braces of - // the compound statement in the zeroed area, so we need to handle this - // specially. + // Make a region for the body of the switch. If the body starts with + // a case, that case will reuse this region; otherwise, this covers + // the unreachable code at the beginning of the switch body. size_t Index = - pushRegion(Counter::getZero(), getStart(CS->body_front()), - getEnd(CS->body_back())); + pushRegion(Counter::getZero(), getStart(CS->body_front())); for (const auto *Child : CS->children()) Visit(Child); + + // Set the end for the body of the switch, if it isn't already set. + for (size_t i = RegionStack.size(); i != Index; --i) { + if (!RegionStack[i - 1].hasEndLoc()) + RegionStack[i - 1].setEndLoc(getEnd(CS->body_back())); + } + popRegions(Index); } } else Modified: cfe/trunk/test/CoverageMapping/switch.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CoverageMapping/switch.cpp?rev=309901&r1=309900&r2=309901&view=diff ============================================================================== --- cfe/trunk/test/CoverageMapping/switch.cpp (original) +++ cfe/trunk/test/CoverageMapping/switch.cpp Wed Aug 2 16:22:50 2017 @@ -3,7 +3,7 @@ // CHECK: foo void foo(int i) { // CHECK-NEXT: File 0, [[@LINE]]:17 -> [[@LINE+8]]:2 = #0 switch(i) { - case 1: // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+3]]:10 = #2 + case 1: // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+1]]:11 = #2 return; case 2: // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+1]]:10 = #3 break; @@ -48,7 +48,7 @@ void baz() { // CHECK-NEXT: File int main() { // CHECK-NEXT: File 0, [[@LINE]]:12 -> [[@LINE+35]]:2 = #0 int i = 0; switch(i) { - case 0: // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+7]]:10 = #2 + case 0: // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+2]]:10 = #2 i = 1; break; case 1: // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+2]]:10 = #3 @@ -58,7 +58,7 @@ int main() { // CHECK-NEXT: File break; } switch(i) { // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+23]]:2 = #1 - case 0: // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+6]]:10 = #6 + case 0: // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+2]]:10 = #6 i = 1; break; case 1: // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+3]]:10 = #7 @@ -81,3 +81,19 @@ int main() { // CHECK-NEXT: File baz(); return 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+12]]:2 = #0 + switch(i) { + case 1: // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+8]]:10 = #2 + i = 23; + case 2: // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+2]]:10 = (#2 + #3) + i = 11; + break; + case 3: // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+3]]:10 = #4 + case 4: // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+2]]:10 = (#4 + #5) + i = 99; + break; + } +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
