[llvm] b7ea298 - [msan] Don't use TLS slots of noundef args
Vitaly Buka via llvm-commits
llvm-commits at lists.llvm.org
Thu Oct 21 18:35:36 PDT 2021
Author: Vitaly Buka
Date: 2021-10-21T18:35:12-07:00
New Revision: b7ea298dfd835a9ff4e5e97d4f145099240ba3aa
URL: https://github.com/llvm/llvm-project/commit/b7ea298dfd835a9ff4e5e97d4f145099240ba3aa
DIFF: https://github.com/llvm/llvm-project/commit/b7ea298dfd835a9ff4e5e97d4f145099240ba3aa.diff
LOG: [msan] Don't use TLS slots of noundef args
Transformations may strip the attribute from the
argument, e.g. for unused, which will result in
shadow offsets mismatch between caller and
callee.
Stripping noundef for used arguments can be
a problem, as TLS is not going to be set
by caller. However this is not the goal of the
patch and I am not aware if that's even
possible.
Differential Revision: https://reviews.llvm.org/D112197
Added:
Modified:
llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
llvm/test/Instrumentation/MemorySanitizer/msan_eager.ll
Removed:
################################################################################
diff --git a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
index ade0d2058e0d1..4d15b784f4860 100644
--- a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
@@ -1758,8 +1758,7 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
break;
}
- if (!FArgEagerCheck)
- ArgOffset += alignTo(Size, kShadowTLSAlignment);
+ ArgOffset += alignTo(Size, kShadowTLSAlignment);
}
assert(*ShadowPtr && "Could not find shadow for an argument");
return *ShadowPtr;
@@ -3709,42 +3708,48 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
if (EagerCheck) {
insertShadowCheck(A, &CB);
- continue;
- }
- if (ByVal) {
- // ByVal requires some special handling as it's too big for a single
- // load
- assert(A->getType()->isPointerTy() &&
- "ByVal argument is not a pointer!");
- Size = DL.getTypeAllocSize(CB.getParamByValType(i));
- if (ArgOffset + Size > kParamTLSSize) break;
- const MaybeAlign ParamAlignment(CB.getParamAlign(i));
- MaybeAlign Alignment = llvm::None;
- if (ParamAlignment)
- Alignment = std::min(*ParamAlignment, kShadowTLSAlignment);
- Value *AShadowPtr =
- getShadowOriginPtr(A, IRB, IRB.getInt8Ty(), Alignment,
- /*isStore*/ false)
- .first;
-
- Store = IRB.CreateMemCpy(ArgShadowBase, Alignment, AShadowPtr,
- Alignment, Size);
- // TODO(glider): need to copy origins.
- } else {
- // Any other parameters mean we need bit-grained tracking of uninit data
Size = DL.getTypeAllocSize(A->getType());
- if (ArgOffset + Size > kParamTLSSize) break;
- Store = IRB.CreateAlignedStore(ArgShadow, ArgShadowBase,
- kShadowTLSAlignment);
- Constant *Cst = dyn_cast<Constant>(ArgShadow);
- if (Cst && Cst->isNullValue()) ArgIsInitialized = true;
+ } else {
+ if (ByVal) {
+ // ByVal requires some special handling as it's too big for a single
+ // load
+ assert(A->getType()->isPointerTy() &&
+ "ByVal argument is not a pointer!");
+ Size = DL.getTypeAllocSize(CB.getParamByValType(i));
+ if (ArgOffset + Size > kParamTLSSize)
+ break;
+ const MaybeAlign ParamAlignment(CB.getParamAlign(i));
+ MaybeAlign Alignment = llvm::None;
+ if (ParamAlignment)
+ Alignment = std::min(*ParamAlignment, kShadowTLSAlignment);
+ Value *AShadowPtr =
+ getShadowOriginPtr(A, IRB, IRB.getInt8Ty(), Alignment,
+ /*isStore*/ false)
+ .first;
+
+ Store = IRB.CreateMemCpy(ArgShadowBase, Alignment, AShadowPtr,
+ Alignment, Size);
+ // TODO(glider): need to copy origins.
+ } else {
+ // Any other parameters mean we need bit-grained tracking of uninit
+ // data
+ Size = DL.getTypeAllocSize(A->getType());
+ if (ArgOffset + Size > kParamTLSSize)
+ break;
+ Store = IRB.CreateAlignedStore(ArgShadow, ArgShadowBase,
+ kShadowTLSAlignment);
+ Constant *Cst = dyn_cast<Constant>(ArgShadow);
+ if (Cst && Cst->isNullValue())
+ ArgIsInitialized = true;
+ }
+ if (MS.TrackOrigins && !ArgIsInitialized)
+ IRB.CreateStore(getOrigin(A),
+ getOriginPtrForArgument(A, IRB, ArgOffset));
+ (void)Store;
+ assert(Store != nullptr);
+ LLVM_DEBUG(dbgs() << " Param:" << *Store << "\n");
}
- if (MS.TrackOrigins && !ArgIsInitialized)
- IRB.CreateStore(getOrigin(A),
- getOriginPtrForArgument(A, IRB, ArgOffset));
- (void)Store;
- assert(Size != 0 && Store != nullptr);
- LLVM_DEBUG(dbgs() << " Param:" << *Store << "\n");
+ assert(Size != 0);
ArgOffset += alignTo(Size, kShadowTLSAlignment);
}
LLVM_DEBUG(dbgs() << " done with call args\n");
diff --git a/llvm/test/Instrumentation/MemorySanitizer/msan_eager.ll b/llvm/test/Instrumentation/MemorySanitizer/msan_eager.ll
index 582d9a9263445..10ab029b5e2cc 100644
--- a/llvm/test/Instrumentation/MemorySanitizer/msan_eager.ll
+++ b/llvm/test/Instrumentation/MemorySanitizer/msan_eager.ll
@@ -69,8 +69,8 @@ define void @NormalArg(i32 noundef %a) nounwind uwtable sanitize_memory {
define void @NormalArgAfterNoUndef(i32 noundef %a, i32 %b) nounwind uwtable sanitize_memory {
; CHECK-LABEL: @NormalArgAfterNoUndef(
-; CHECK-NEXT: [[TMP1:%.*]] = load i32, i32* bitcast ([100 x i64]* @__msan_param_tls to i32*), align 8
-; CHECK-NEXT: [[TMP2:%.*]] = load i32, i32* getelementptr inbounds ([200 x i32], [200 x i32]* @__msan_param_origin_tls, i32 0, i32 0), align 4
+; CHECK-NEXT: [[TMP1:%.*]] = load i32, i32* inttoptr (i64 add (i64 ptrtoint ([100 x i64]* @__msan_param_tls to i64), i64 8) to i32*), align 8
+; CHECK-NEXT: [[TMP2:%.*]] = load i32, i32* inttoptr (i64 add (i64 ptrtoint ([200 x i32]* @__msan_param_origin_tls to i64), i64 8) to i32*), align 4
; CHECK-NEXT: call void @llvm.donothing()
; CHECK-NEXT: [[P:%.*]] = inttoptr i64 0 to i32*
; CHECK-NEXT: [[TMP3:%.*]] = ptrtoint i32* [[P]] to i64
@@ -135,7 +135,7 @@ define void @CallNormalArgAfterNoUndef() nounwind uwtable sanitize_memory {
; CHECK-LABEL: @CallNormalArgAfterNoUndef(
; CHECK-NEXT: call void @llvm.donothing()
; CHECK-NEXT: [[R:%.*]] = call i32 @NormalRet() #[[ATTR0]]
-; CHECK-NEXT: store i32 0, i32* bitcast ([100 x i64]* @__msan_param_tls to i32*), align 8
+; CHECK-NEXT: store i32 0, i32* inttoptr (i64 add (i64 ptrtoint ([100 x i64]* @__msan_param_tls to i64), i64 8) to i32*), align 8
; CHECK-NEXT: call void @NormalArgAfterNoUndef(i32 [[R]], i32 [[R]]) #[[ATTR0]]
; CHECK-NEXT: ret void
;
More information about the llvm-commits
mailing list