Index: lib/Transforms/Instrumentation/AddressSanitizer.cpp =================================================================== --- lib/Transforms/Instrumentation/AddressSanitizer.cpp +++ lib/Transforms/Instrumentation/AddressSanitizer.cpp @@ -211,6 +211,8 @@ "Number of optimized accesses to global arrays"); STATISTIC(NumOptimizedAccessesToGlobalVar, "Number of optimized accesses to global vars"); +STATISTIC(NumOptimizedAccessesToStackVar, + "Number of optimized accesses to stack vars"); namespace { /// Frontend-provided metadata for source location. @@ -876,6 +878,22 @@ } } + // A direct inbounds access to a stack variable is always valid. + if (isa(Addr->stripInBoundsConstantOffsets())) { + NumOptimizedAccessesToStackVar++; + return; + } +/* + This does not give the desired result. + if (ConstantExpr *CE = dyn_cast(Addr)) { + if (CE->isGEPWithNoNotionalOverIndexing() && + isa(CE->getOperand(0))) { + NumOptimizedAccessesToStackVar++; + return; + } + } +*/ + Type *OrigPtrTy = Addr->getType(); Type *OrigTy = cast(OrigPtrTy)->getElementType(); Index: test/Instrumentation/AddressSanitizer/instrument-stack.ll =================================================================== --- test/Instrumentation/AddressSanitizer/instrument-stack.ll +++ test/Instrumentation/AddressSanitizer/instrument-stack.ll @@ -0,0 +1,46 @@ +; This test checks that we are not instrumenting direct inbound stack accesses. +; RUN: opt < %s -asan -asan-module -S | FileCheck %s + +target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +;@sink = global i32* null, align 4 + +define void @foo() uwtable sanitize_address { +entry: + %a = alloca i32, align 4 + store i32 42, i32* %a, align 4 + ret void +; CHECK-LABEL: define void @foo +; CHECK-NOT: __asan_report +; CHECK: ret void +} + +define void @baz(i64 %i) sanitize_address { +entry: + %a = alloca [10 x i32], align 4 + %e = getelementptr inbounds [10 x i32]* %a, i32 0, i64 %i + store i32 42, i32* %e, align 4 + ret void +; CHECK-LABEL: define void @baz +; CHECK: __asan_report +; CHECK: ret void +} + +define void @bar() sanitize_address { +entry: + %a = alloca [10 x i32], align 4 + %e = getelementptr inbounds [10 x i32]* %a, i32 0, i64 12 + store i32 42, i32* %e, align 4 + ret void +; CHECK-LABEL: define void @bar +; CHECK: __asan_report +; CHECK: ret void +} + +define void @endoftests() sanitize_address { +entry: + ret void +; CHECK-LABEL: define void @endoftests +} +