Usage of atomic counters for llvm code coverage

Dushistov · Dushistov · commit 6b58ff5cdf47 · 2023-05-12T01:40:04.000+03:00
diff --git a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
@@ -745,6 +745,9 @@ LLVMRustOptimize(
         if (InstrProfileOutput) {
           Options.InstrProfileOutput = InstrProfileOutput;
         }
+        // cargo run tests in multhreading mode by default
+        // so use atomics for coverage counters
+        Options.Atomic = true;
         MPM.addPass(InstrProfiling(Options, false));
       }
     );
diff --git a/tests/run-make/coverage-llvmir/filecheck.testprog.txt b/tests/run-make/coverage-llvmir/filecheck.testprog.txt
@@ -36,7 +36,7 @@ CHECK-SAME:   section "llvm.metadata"
 CHECK:        [[DEFINE_INTERNAL]] { {{.*}} } @_R{{[a-zA-Z0-9_]+}}testprog14will_be_called() unnamed_addr #{{[0-9]+}} {
 CHECK-NEXT:   start:
 CHECK-NOT:    [[DEFINE_INTERNAL]]
-CHECK:        %pgocount = load i64, {{i64\*|ptr}}
+CHECK:        atomicrmw add ptr
 CHECK-SAME:   @__profc__R{{[a-zA-Z0-9_]+}}testprog14will_be_called,
 
 CHECK:        declare void @llvm.instrprof.increment({{i8\*|ptr}}, i64, i32, i32) #[[LLVM_INSTRPROF_INCREMENT_ATTR:[0-9]+]]

Original file line number	Diff line number	Diff line change
`@@ -745,6 +745,9 @@ LLVMRustOptimize(`
`745`	`745`	`if (InstrProfileOutput) {`
`746`	`746`	`Options.InstrProfileOutput = InstrProfileOutput;`
`747`	`747`	`}`
	`748`	`+ // cargo run tests in multhreading mode by default`
	`749`	`+ // so use atomics for coverage counters`
	`750`	`+ Options.Atomic = true;`
`748`	`751`	`MPM.addPass(InstrProfiling(Options, false));`
`749`	`752`	`}`
`750`	`753`	`);`