diff --git a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp --- a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp +++ b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp @@ -4068,6 +4068,12 @@ setOrigin(&I, getCleanOrigin()); } + void visitFreezeInst(FreezeInst &I) { + // Freeze always returns a fully defined value. + setShadow(&I, getCleanShadow(&I)); + setOrigin(&I, getCleanOrigin()); + } + void visitInstruction(Instruction &I) { // Everything else: stop propagating and check for poisoned shadow. if (ClDumpStrictInstructions) diff --git a/llvm/test/Instrumentation/MemorySanitizer/freeze.ll b/llvm/test/Instrumentation/MemorySanitizer/freeze.ll new file mode 100644 --- /dev/null +++ b/llvm/test/Instrumentation/MemorySanitizer/freeze.ll @@ -0,0 +1,23 @@ +; RUN: opt < %s -msan-check-access-address=0 -S -passes=msan 2>&1 | FileCheck %s +; RUN: opt < %s -msan-check-access-address=0 -msan-track-origins=2 -S -passes=msan 2>&1 | FileCheck %s -check-prefixes=CHECK,CHECK-ORIGIN +; RUN: opt < %s -msan -msan-check-access-address=0 -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" + +define i32 @nofreeze(i32* %ptr) sanitize_memory { + ; CHECK-LABEL: @nofreeze + %val = load i32, i32* %ptr + ; CHECK: [[SHADOW_PTR:%.*]] = inttoptr + ; CHECK: [[SHADOW:%.*]] = load i32, i32* [[SHADOW_PTR]] + ; CHECK: store i32 [[SHADOW]], {{.*}} @__msan_retval_tls + ret i32 %val +} + +define i32 @freeze_inst(i32* %ptr) sanitize_memory { + ; CHECK-LABEL: @freeze_inst + %val = load i32, i32* %ptr + %freeze_val = freeze i32 %val + ; CHECK-NOT: __msan_warning + ; CHECK: store i32 0, {{.*}} @__msan_retval_tls + ret i32 %freeze_val +}