~TargetLoweringObjectFileXCOFF() override = default;
static bool ShouldEmitEHBlock(const MachineFunction *MF);
+ static bool ShouldSetSSPCanaryBitInTB(const MachineFunction *MF);
static MCSymbol *getEHInfoTableSymbol(const MachineFunction *MF);
return true;
}
+bool TargetLoweringObjectFileXCOFF::ShouldSetSSPCanaryBitInTB(
+ const MachineFunction *MF) {
+ const Function &F = MF->getFunction();
+ if (!F.hasStackProtectorFnAttr())
+ return false;
+ // FIXME: check presence of canary word
+ // There are cases that the stack protectors are not really inserted even if
+ // the attributes are on.
+ return true;
+}
+
MCSymbol *
TargetLoweringObjectFileXCOFF::getEHInfoTableSymbol(const MachineFunction *MF) {
return MF->getMMI().getContext().getOrCreateSymbol(
#define DEBUG_TYPE "asmprinter"
+static cl::opt<bool> EnableSSPCanaryBitInTB(
+ "aix-ssp-tb-bit", cl::init(false),
+ cl::desc("Enable Passing SSP Canary info in Trackback on AIX"), cl::Hidden);
+
// Specialize DenseMapInfo to allow
// std::pair<const MCSymbol *, MCSymbolRefExpr::VariantKind> in DenseMap.
// This specialization is needed here because that type is used as keys in the
if (SecondHalfOfMandatoryField & TracebackTable::HasExtensionTableMask) {
if (ShouldEmitEHBlock)
ExtensionTableFlag |= ExtendedTBTableFlag::TB_EH_INFO;
+ if (EnableSSPCanaryBitInTB &&
+ TargetLoweringObjectFileXCOFF::ShouldSetSSPCanaryBitInTB(MF))
+ ExtensionTableFlag |= ExtendedTBTableFlag::TB_SSP_CANARY;
CommentOS << "ExtensionTableFlag = "
<< getExtendedTBTableFlagString(ExtensionTableFlag);
--- /dev/null
+; RUN: llc -aix-ssp-tb-bit -mtriple=powerpc64-ibm-aix-xcoff -O0 < %s | FileCheck %s
+
+; CHECK-LABEL: f:
+; CHECK: __ssp_canary_word
+; CHECK: TB_SSP_CANARY
+define i32 @f() #0 personality i8* bitcast (i32 (...)* @__xlcxx_personality_v1 to i8*) {
+ invoke i32 undef(i8* undef)
+ to label %invoke unwind label %lpad
+
+ invoke:
+ %var = alloca i32, align 4
+ store i32 0, i32* %var, align 4
+ %gep = getelementptr inbounds i32, i32* %var, i32 1
+ %ret = load i32, i32* %gep, align 4
+ ret i32 %ret
+ lpad:
+ landingpad { i8*, i32 }
+ catch i8* null
+ unreachable
+
+}
+
+; CHECK-LABEL: f2:
+; CHECK: __ssp_canary_word
+; Not emitting traceback bit when no unwinding needed.
+; CHECK-NOT: TB_SSP_CANARY
+define i32 @f2() #0 {
+ %var = alloca i32, align 4
+ store i32 0, i32* %var, align 4
+ %gep = getelementptr inbounds i32, i32* %var, i32 1
+ %ret = load i32, i32* %gep, align 4
+ ret i32 %ret
+}
+
+declare i32 @__xlcxx_personality_v1(...)
+attributes #0 = { sspstrong }
+