Author: efriedma Date: Thu Aug 3 15:27:36 2017 New Revision: 309995 URL: http://llvm.org/viewvc/llvm-project?rev=309995&view=rev Log: [coverage] Special-case calls to noreturn functions.
The code after a noreturn call doesn't execute. The pattern in the testcase is pretty common in LLVM (a switch with a default case that calls llvm_unreachable). Differential Revision: https://reviews.llvm.org/D36250 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=309995&r1=309994&r2=309995&view=diff ============================================================================== --- cfe/trunk/lib/CodeGen/CoverageMappingGen.cpp (original) +++ cfe/trunk/lib/CodeGen/CoverageMappingGen.cpp Thu Aug 3 15:27:36 2017 @@ -716,6 +716,18 @@ struct CounterCoverageMappingBuilder terminateRegion(S); } + void VisitCallExpr(const CallExpr *E) { + extendRegion(E); + for (const Stmt *Child : E->children()) + this->Visit(Child); + + // Terminate the region when we hit a noreturn function. + // (This is helpful dealing with switch statements.) + QualType CalleeType = E->getCallee()->getType(); + if (getFunctionExtInfo(*CalleeType).getNoReturn()) + terminateRegion(E); + } + void VisitWhileStmt(const WhileStmt *S) { extendRegion(S); Modified: cfe/trunk/test/CoverageMapping/switch.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CoverageMapping/switch.cpp?rev=309995&r1=309994&r2=309995&view=diff ============================================================================== --- cfe/trunk/test/CoverageMapping/switch.cpp (original) +++ cfe/trunk/test/CoverageMapping/switch.cpp Thu Aug 3 15:27:36 2017 @@ -97,3 +97,16 @@ int fallthrough(int i) { // CHECK-NEXT: break; } } + +void abort(void) __attribute((noreturn)); + // CHECK: noret +int noret(int x) { // CHECK-NEXT: File 0, [[@LINE]]:18 -> [[@LINE+9]]:2 + switch (x) { + default: // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+1]]:12 + abort(); + case 1: // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+1]]:13 + return 5; + case 2: // CHECK-NEXT: File 0, [[@LINE]]:3 -> [[@LINE+1]]:14 + return 10; + } +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
