[LLVM] Make sanitizers respect the disable_santizer_instrumentation attribute.

llvm/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp

@@ -1546,7 +1546,8 @@ bool DataFlowSanitizer::runImpl(
   SmallPtrSet<Constant *, 1> PersonalityFns;
   for (Function &F : M)
     if (!F.isIntrinsic() && !DFSanRuntimeFunctions.contains(&F) &&
-        !LibAtomicFunction(F)) {
+        !LibAtomicFunction(F) &&
+        !F.hasFnAttribute(Attribute::DisableSanitizerInstrumentation)) {
       FnsToInstrument.push_back(&F);
       if (F.hasPersonalityFn())
         PersonalityFns.insert(F.getPersonalityFn()->stripPointerCasts());

llvm/lib/Transforms/Instrumentation/SanitizerCoverage.cpp

@@ -631,6 +631,8 @@ void ModuleSanitizerCoverage::instrumentFunction(Function &F) {
     return;
   if (F.hasFnAttribute(Attribute::NoSanitizeCoverage))
     return;
+  if (F.hasFnAttribute(Attribute::DisableSanitizerInstrumentation))
+    return;
   if (Options.CoverageType >= SanitizerCoverageOptions::SCK_Edge) {
     SplitAllCriticalEdges(
         F, CriticalEdgeSplittingOptions().setIgnoreUnreachableDests());

llvm/test/Instrumentation/DataFlowSanitizer/dataflow-disable-sanitizer-instrumentation.ll

@@ -0,0 +1,47 @@
+
+; This test checks that we are not instrumenting sanitizer code.
+; RUN: opt < %s -passes='module(msan)' -S | FileCheck %s
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+; Function with sanitize_memory is instrumented.
+; Function Attrs: nounwind uwtable
+define void @instr_sa(ptr %a) sanitize_memory {
+entry:
+  %tmp1 = load i32, ptr %a, align 4
+  %tmp2 = add i32 %tmp1,  1
+  store i32 %tmp2, ptr %a, align 4
+  ret void
+}
+
+; CHECK-LABEL: @instr_sa
+; CHECK: %0 = load i64, ptr @__msan_param_tls
+
+
+; Function with disable_sanitizer_instrumentation is not instrumented.
+; Function Attrs: nounwind uwtable
+define void @noinstr_dsi(ptr %a) disable_sanitizer_instrumentation {
+entry:
+  %tmp1 = load i32, ptr %a, align 4
+  %tmp2 = add i32 %tmp1,  1
+  store i32 %tmp2, ptr %a, align 4
+  ret void
+}
+
+; CHECK-LABEL: @noinstr_dsi
+; CHECK-NOT: %0 = load i64, ptr @__msan_param_tls
+
+
+; disable_sanitizer_instrumentation takes precedence over sanitize_memory.
+; Function Attrs: nounwind uwtable
+define void @noinstr_dsi_sa(ptr %a) disable_sanitizer_instrumentation sanitize_memory {
+entry:
+  %tmp1 = load i32, ptr %a, align 4
+  %tmp2 = add i32 %tmp1,  1
+  store i32 %tmp2, ptr %a, align 4
+  ret void
+}
+
+; CHECK-LABEL: @noinstr_dsi_sa
+; CHECK-NOT: %0 = load i64, ptr @__msan_param_tls

llvm/test/Instrumentation/SanitizerCoverage/coverage-disable-sanitizer-instrumentation.ll

@@ -0,0 +1,46 @@
+; This test checks that we are not instrumenting sanitizer code.
+; RUN: opt < %s -passes='module(sancov-module)' -sanitizer-coverage-level=3 -sanitizer-coverage-control-flow -S | FileCheck %s
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+; Function with sanitize_address is instrumented.
+; Function Attrs: nounwind uwtable
+define void @instr_sa(ptr %a) sanitize_address {
+entry:
+  %tmp1 = load i32, ptr %a, align 4
+  %tmp2 = add i32 %tmp1,  1
+  store i32 %tmp2, ptr %a, align 4
+  ret void
+}
+
+; CHECK-LABEL: @instr_sa
+; CHECK: call void @__sanitizer_cov_trace_pc_guard(
+
+
+; Function with disable_sanitizer_instrumentation is not instrumented.
+; Function Attrs: nounwind uwtable
+define void @noinstr_dsi(ptr %a) disable_sanitizer_instrumentation {
+entry:
+  %tmp1 = load i32, ptr %a, align 4
+  %tmp2 = add i32 %tmp1,  1
+  store i32 %tmp2, ptr %a, align 4
+  ret void
+}
+
+; CHECK-LABEL: @noinstr_dsi
+; CHECK-NOT: call void @__sanitizer_cov_trace_pc_guard(
+
+
+; disable_sanitizer_instrumentation takes precedence over sanitize_address.
+; Function Attrs: nounwind uwtable
+define void @noinstr_dsi_sa(ptr %a) disable_sanitizer_instrumentation sanitize_address {
+entry:
+  %tmp1 = load i32, ptr %a, align 4
+  %tmp2 = add i32 %tmp1,  1
+  store i32 %tmp2, ptr %a, align 4
+  ret void
+}
+
+; CHECK-LABEL: @noinstr_dsi_sa
+; CHECK-NOT: call void @__sanitizer_cov_trace_pc_guard(