[llvm] r214561 - [dfsan] Correctly handle loads and stores of zero size.

[Peter Collingbourne]

Author: pcc
Date: Fri Aug  1 16:18:18 2014
New Revision: 214561

URL: http://llvm.org/viewvc/llvm-project?rev=214561&view=rev
Log:
[dfsan] Correctly handle loads and stores of zero size.

Modified:
    llvm/trunk/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp
    llvm/trunk/test/Instrumentation/DataFlowSanitizer/load.ll
    llvm/trunk/test/Instrumentation/DataFlowSanitizer/store.ll

Modified: llvm/trunk/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp?rev=214561&r1=214560&r2=214561&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp (original)
+++ llvm/trunk/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp Fri Aug  1 16:18:18 2014
@@ -1092,6 +1092,11 @@ Value *DFSanFunction::loadShadow(Value *
 
 void DFSanVisitor::visitLoadInst(LoadInst &LI) {
   uint64_t Size = DFSF.DFS.DL->getTypeStoreSize(LI.getType());
+  if (Size == 0) {
+    DFSF.setShadow(&LI, DFSF.DFS.ZeroShadow);
+    return;
+  }
+
   uint64_t Align;
   if (ClPreserveAlignment) {
     Align = LI.getAlignment();
@@ -1166,6 +1171,9 @@ void DFSanFunction::storeShadow(Value *A
 void DFSanVisitor::visitStoreInst(StoreInst &SI) {
   uint64_t Size =
       DFSF.DFS.DL->getTypeStoreSize(SI.getValueOperand()->getType());
+  if (Size == 0)
+    return;
+
   uint64_t Align;
   if (ClPreserveAlignment) {
     Align = SI.getAlignment();

Modified: llvm/trunk/test/Instrumentation/DataFlowSanitizer/load.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Instrumentation/DataFlowSanitizer/load.ll?rev=214561&r1=214560&r2=214561&view=diff
==============================================================================
--- llvm/trunk/test/Instrumentation/DataFlowSanitizer/load.ll (original)
+++ llvm/trunk/test/Instrumentation/DataFlowSanitizer/load.ll Fri Aug  1 16:18:18 2014
@@ -2,6 +2,18 @@
 ; RUN: opt < %s -dfsan -dfsan-combine-pointer-labels-on-load=0 -S | FileCheck %s --check-prefix=NO_COMBINE_PTR_LABEL
 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"
 
+define {} @load0({}* %p) {
+  ; COMBINE_PTR_LABEL: @"dfs$load0"
+  ; COMBINE_PTR_LABEL: load
+  ; COMBINE_PTR_LABEL-NOT: load
+
+  ; NO_COMBINE_PTR_LABEL: @"dfs$load0"
+  ; NO_COMBINE_PTR_LABEL: load
+  ; NO_COMBINE_PTR_LABEL-NOT: load
+  %a = load {}* %p
+  ret {} %a
+}
+
 define i8 @load8(i8* %p) {
   ; COMBINE_PTR_LABEL: @"dfs$load8"
   ; COMBINE_PTR_LABEL: load i16*
@@ -152,4 +164,4 @@ define i64 @load64(i64* %p) {
 
   %a = load i64* %p
   ret i64 %a
-}
\ No newline at end of file
+}

Modified: llvm/trunk/test/Instrumentation/DataFlowSanitizer/store.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Instrumentation/DataFlowSanitizer/store.ll?rev=214561&r1=214560&r2=214561&view=diff
==============================================================================
--- llvm/trunk/test/Instrumentation/DataFlowSanitizer/store.ll (original)
+++ llvm/trunk/test/Instrumentation/DataFlowSanitizer/store.ll Fri Aug  1 16:18:18 2014
@@ -2,6 +2,19 @@
 ; RUN: opt < %s -dfsan -dfsan-combine-pointer-labels-on-store=0 -S | FileCheck %s --check-prefix=NO_COMBINE_PTR_LABEL
 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"
 
+define void @store0({} %v, {}* %p) {
+  ; COMBINE_PTR_LABEL: @"dfs$store0"
+  ; COMBINE_PTR_LABEL: store
+  ; COMBINE_PTR_LABEL-NOT: store
+
+  ; NO_COMBINE_PTR_LABEL: @"dfs$store0"
+  ; NO_COMBINE_PTR_LABEL: store
+  ; NO_COMBINE_PTR_LABEL-NOT: store
+
+  store {} %v, {}* %p
+  ret void
+}
+
 define void @store8(i8 %v, i8* %p) {
   ; NO_COMBINE_PTR_LABEL: @"dfs$store8"
   ; NO_COMBINE_PTR_LABEL: load i16* {{.*}} @__dfsan_arg_tls