[llvm] r212872 - [ASan] Collect unmangled names of global variables in Clang to print them in error reports.
Alexey Samsonov
vonosmas at gmail.com
Fri Jul 11 17:42:52 PDT 2014
Author: samsonov
Date: Fri Jul 11 19:42:52 2014
New Revision: 212872
URL: http://llvm.org/viewvc/llvm-project?rev=212872&view=rev
Log:
[ASan] Collect unmangled names of global variables in Clang to print them in error reports.
Currently ASan instrumentation pass creates a string with global name
for each instrumented global (to include global names in the error report). Global
name is already mangled at this point, and we may not be able to demangle it
at runtime (e.g. there is no __cxa_demangle on Android).
Instead, create a string with fully qualified global name in Clang, and pass it
to ASan instrumentation pass in llvm.asan.globals metadata. If there is no metadata
for some global, ASan will use the original algorithm.
This fixes https://code.google.com/p/address-sanitizer/issues/detail?id=264.
Modified:
llvm/trunk/lib/Transforms/Instrumentation/AddressSanitizer.cpp
llvm/trunk/test/Instrumentation/AddressSanitizer/global_metadata.ll
llvm/trunk/test/Instrumentation/AddressSanitizer/instrument_global.ll
llvm/trunk/test/Instrumentation/AddressSanitizer/instrument_initializer_metadata.ll
Modified: llvm/trunk/lib/Transforms/Instrumentation/AddressSanitizer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Instrumentation/AddressSanitizer.cpp?rev=212872&r1=212871&r2=212872&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Instrumentation/AddressSanitizer.cpp (original)
+++ llvm/trunk/lib/Transforms/Instrumentation/AddressSanitizer.cpp Fri Jul 11 19:42:52 2014
@@ -216,8 +216,11 @@ namespace {
class GlobalsMetadata {
public:
struct Entry {
- Entry() : SourceLoc(nullptr), IsDynInit(false), IsBlacklisted(false) {}
+ Entry()
+ : SourceLoc(nullptr), Name(nullptr), IsDynInit(false),
+ IsBlacklisted(false) {}
GlobalVariable *SourceLoc;
+ GlobalVariable *Name;
bool IsDynInit;
bool IsBlacklisted;
};
@@ -232,7 +235,7 @@ class GlobalsMetadata {
return;
for (auto MDN : Globals->operands()) {
// Metadata node contains the global and the fields of "Entry".
- assert(MDN->getNumOperands() == 4);
+ assert(MDN->getNumOperands() == 5);
Value *V = MDN->getOperand(0);
// The optimizer may optimize away a global entirely.
if (!V)
@@ -246,9 +249,14 @@ class GlobalsMetadata {
E.SourceLoc = GVLoc;
addSourceLocationGlobal(GVLoc);
}
- ConstantInt *IsDynInit = cast<ConstantInt>(MDN->getOperand(2));
+ if (Value *Name = MDN->getOperand(2)) {
+ GlobalVariable *GVName = cast<GlobalVariable>(Name);
+ E.Name = GVName;
+ InstrumentationGlobals.insert(GVName);
+ }
+ ConstantInt *IsDynInit = cast<ConstantInt>(MDN->getOperand(3));
E.IsDynInit |= IsDynInit->isOne();
- ConstantInt *IsBlacklisted = cast<ConstantInt>(MDN->getOperand(3));
+ ConstantInt *IsBlacklisted = cast<ConstantInt>(MDN->getOperand(4));
E.IsBlacklisted |= IsBlacklisted->isOne();
}
}
@@ -1049,6 +1057,14 @@ bool AddressSanitizerModule::InstrumentG
for (size_t i = 0; i < n; i++) {
static const uint64_t kMaxGlobalRedzone = 1 << 18;
GlobalVariable *G = GlobalsToChange[i];
+
+ auto MD = GlobalsMD.get(G);
+ // Create string holding the global name unless it was provided by
+ // the metadata.
+ GlobalVariable *Name =
+ MD.Name ? MD.Name : createPrivateGlobalForString(M, G->getName(),
+ /*AllowMerging*/ true);
+
PointerType *PtrTy = cast<PointerType>(G->getType());
Type *Ty = PtrTy->getElementType();
uint64_t SizeInBytes = DL->getTypeAllocSize(Ty);
@@ -1070,9 +1086,6 @@ bool AddressSanitizerModule::InstrumentG
NewTy, G->getInitializer(),
Constant::getNullValue(RightRedZoneTy), NULL);
- GlobalVariable *Name =
- createPrivateGlobalForString(M, G->getName(), /*AllowMerging*/true);
-
// Create a new global variable with enough space for a redzone.
GlobalValue::LinkageTypes Linkage = G->getLinkage();
if (G->isConstant() && Linkage == GlobalValue::PrivateLinkage)
@@ -1092,8 +1105,6 @@ bool AddressSanitizerModule::InstrumentG
NewGlobal->takeName(G);
G->eraseFromParent();
- auto MD = GlobalsMD.get(G);
-
Initializers[i] = ConstantStruct::get(
GlobalStructTy, ConstantExpr::getPointerCast(NewGlobal, IntptrTy),
ConstantInt::get(IntptrTy, SizeInBytes),
Modified: llvm/trunk/test/Instrumentation/AddressSanitizer/global_metadata.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Instrumentation/AddressSanitizer/global_metadata.ll?rev=212872&r1=212871&r2=212872&view=diff
==============================================================================
--- llvm/trunk/test/Instrumentation/AddressSanitizer/global_metadata.ll (original)
+++ llvm/trunk/test/Instrumentation/AddressSanitizer/global_metadata.ll Fri Jul 11 19:42:52 2014
@@ -18,12 +18,20 @@ target triple = "x86_64-unknown-linux-gn
@.asan_loc_descr2 = private unnamed_addr constant { [22 x i8]*, i32, i32 } { [22 x i8]* @.str1, i32 12, i32 14 }
@.asan_loc_descr4 = private unnamed_addr constant { [22 x i8]*, i32, i32 } { [22 x i8]* @.str1, i32 14, i32 25 }
+; Global names:
+ at .str2 = private unnamed_addr constant [7 x i8] c"global\00", align 1
+ at .str3 = private unnamed_addr constant [16 x i8] c"dyn_init_global\00", align 1
+ at .str4 = private unnamed_addr constant [11 x i8] c"static_var\00", align 1
+ at .str5 = private unnamed_addr constant [17 x i8] c"<string literal>\00", align 1
+
; Check that globals were instrumented, but sanitizer location descriptors weren't:
; CHECK: @global = global { i32, [60 x i8] } zeroinitializer, align 32
; CHECK: @.str = internal unnamed_addr constant { [14 x i8], [50 x i8] } { [14 x i8] c"Hello, world!\00", [50 x i8] zeroinitializer }, align 32
; CHECK: @.asan_loc_descr = private unnamed_addr constant { [22 x i8]*, i32, i32 } { [22 x i8]* @.str1, i32 5, i32 5 }
+; CHECK: @.str2 = private unnamed_addr constant [7 x i8] c"global\00", align 1
-; Check that location decriptors were passed into __asan_register_globals:
+; Check that location decriptors and global names were passed into __asan_register_globals:
+; CHECK: i64 ptrtoint ([7 x i8]* @.str2 to i64)
; CHECK: i64 ptrtoint ({ [22 x i8]*, i32, i32 }* @.asan_loc_descr to i64)
; Function Attrs: nounwind sanitize_address
@@ -55,9 +63,9 @@ attributes #1 = { nounwind sanitize_addr
!llvm.asan.globals = !{!0, !1, !2, !3, !4}
!llvm.ident = !{!5}
-!0 = metadata !{i32* @global, { [22 x i8]*, i32, i32 }* @.asan_loc_descr, i1 false, i1 false}
-!1 = metadata !{i32* @dyn_init_global, { [22 x i8]*, i32, i32 }* @.asan_loc_descr1, i1 true, i1 false}
-!2 = metadata !{i32* @blacklisted_global, null, i1 false, i1 true}
-!3 = metadata !{i32* @_ZZ4funcvE10static_var, { [22 x i8]*, i32, i32 }* @.asan_loc_descr2, i1 false, i1 false}
-!4 = metadata !{[14 x i8]* @.str, { [22 x i8]*, i32, i32 }* @.asan_loc_descr4, i1 false, i1 false}
+!0 = metadata !{i32* @global, { [22 x i8]*, i32, i32 }* @.asan_loc_descr, [7 x i8]* @.str2, i1 false, i1 false}
+!1 = metadata !{i32* @dyn_init_global, { [22 x i8]*, i32, i32 }* @.asan_loc_descr1, [16 x i8]* @.str3, i1 true, i1 false}
+!2 = metadata !{i32* @blacklisted_global, null, null, i1 false, i1 true}
+!3 = metadata !{i32* @_ZZ4funcvE10static_var, { [22 x i8]*, i32, i32 }* @.asan_loc_descr2, [11 x i8]* @.str4, i1 false, i1 false}
+!4 = metadata !{[14 x i8]* @.str, { [22 x i8]*, i32, i32 }* @.asan_loc_descr4, [17 x i8]* @.str5, i1 false, i1 false}
!5 = metadata !{metadata !"clang version 3.5.0 (211282)"}
Modified: llvm/trunk/test/Instrumentation/AddressSanitizer/instrument_global.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Instrumentation/AddressSanitizer/instrument_global.ll?rev=212872&r1=212871&r2=212872&view=diff
==============================================================================
--- llvm/trunk/test/Instrumentation/AddressSanitizer/instrument_global.ll (original)
+++ llvm/trunk/test/Instrumentation/AddressSanitizer/instrument_global.ll Fri Jul 11 19:42:52 2014
@@ -69,7 +69,7 @@ entry:
!llvm.asan.globals = !{!0}
-!0 = metadata !{[10 x i32]* @GlobDy, null, i1 true, i1 false}
+!0 = metadata !{[10 x i32]* @GlobDy, null, null, i1 true, i1 false}
; CHECK-LABEL: define internal void @asan.module_ctor
; CHECK-NOT: ret
Modified: llvm/trunk/test/Instrumentation/AddressSanitizer/instrument_initializer_metadata.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Instrumentation/AddressSanitizer/instrument_initializer_metadata.ll?rev=212872&r1=212871&r2=212872&view=diff
==============================================================================
--- llvm/trunk/test/Instrumentation/AddressSanitizer/instrument_initializer_metadata.ll (original)
+++ llvm/trunk/test/Instrumentation/AddressSanitizer/instrument_initializer_metadata.ll Fri Jul 11 19:42:52 2014
@@ -7,10 +7,10 @@ target triple = "x86_64-unknown-linux-gn
@YYY = global i32 0, align 4 ; W/o dynamic initializer.
; Clang will emit the following metadata identifying @xxx as dynamically
; initialized.
-!0 = metadata !{i32* @xxx, null, i1 true, i1 false}
-!1 = metadata !{i32* @XXX, null, i1 true, i1 false}
-!2 = metadata !{i32* @yyy, null, i1 false, i1 false}
-!3 = metadata !{i32* @YYY, null, i1 false, i1 false}
+!0 = metadata !{i32* @xxx, null, null, i1 true, i1 false}
+!1 = metadata !{i32* @XXX, null, null, i1 true, i1 false}
+!2 = metadata !{i32* @yyy, null, null, i1 false, i1 false}
+!3 = metadata !{i32* @YYY, null, null, i1 false, i1 false}
!llvm.asan.globals = !{!0, !1, !2, !3}
define i32 @initializer() uwtable {
More information about the llvm-commits
mailing list