[llvm] [aarch64] XOR the frame pointer with the stack cookie when protecting the stack (PR #161114)

Pan Tao via llvm-commits llvm-commits at lists.llvm.org
Wed Oct 29 01:08:35 PDT 2025


https://github.com/PanTao2 updated https://github.com/llvm/llvm-project/pull/161114

>From 9c6d4c7ef323e45a8171b63517e05a510aef1f84 Mon Sep 17 00:00:00 2001
From: "Pan, Tao" <tao.pan at intel.com>
Date: Mon, 29 Sep 2025 09:43:17 +0800
Subject: [PATCH 1/7] [aarch64] XOR the frame pointer with the stack cookie
 when protecting the stack

---
 llvm/lib/Target/AArch64/AArch64ISelLowering.cpp     | 12 +++++++++++-
 llvm/lib/Target/AArch64/AArch64ISelLowering.h       |  3 +++
 llvm/lib/Target/AArch64/AArch64SelectionDAGInfo.cpp |  2 +-
 3 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
index a4c1e265f0e63..fffc060bbe7cd 100644
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -28818,7 +28818,17 @@ void AArch64TargetLowering::ReplaceNodeResults(
 bool AArch64TargetLowering::useLoadStackGuardNode(const Module &M) const {
   if (Subtarget->isTargetAndroid() || Subtarget->isTargetFuchsia())
     return TargetLowering::useLoadStackGuardNode(M);
-  return true;
+  return false;
+}
+
+bool AArch64TargetLowering::useStackGuardXorFP() const { return true; }
+
+SDValue AArch64TargetLowering::emitStackGuardXorFP(SelectionDAG &DAG,
+                                                   SDValue Val,
+                                                   const SDLoc &DL) const {
+  return DAG.getNode(
+      ISD::XOR, DL, Val.getValueType(), Val,
+      DAG.getRegister(getStackPointerRegisterToSaveRestore(), MVT::i64));
 }
 
 unsigned AArch64TargetLowering::combineRepeatedFPDivisors() const {
diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.h b/llvm/lib/Target/AArch64/AArch64ISelLowering.h
index d8072d15853ee..8073b0677a11b 100644
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.h
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.h
@@ -349,6 +349,9 @@ class AArch64TargetLowering : public TargetLowering {
   shouldExpandAtomicCmpXchgInIR(AtomicCmpXchgInst *AI) const override;
 
   bool useLoadStackGuardNode(const Module &M) const override;
+  bool useStackGuardXorFP() const override;
+  SDValue emitStackGuardXorFP(SelectionDAG &DAG, SDValue Val,
+                              const SDLoc &DL) const override;
   TargetLoweringBase::LegalizeTypeAction
   getPreferredVectorAction(MVT VT) const override;
 
diff --git a/llvm/lib/Target/AArch64/AArch64SelectionDAGInfo.cpp b/llvm/lib/Target/AArch64/AArch64SelectionDAGInfo.cpp
index d3b1aa621b61a..163de52386221 100644
--- a/llvm/lib/Target/AArch64/AArch64SelectionDAGInfo.cpp
+++ b/llvm/lib/Target/AArch64/AArch64SelectionDAGInfo.cpp
@@ -32,7 +32,7 @@ AArch64SelectionDAGInfo::AArch64SelectionDAGInfo()
 
 void AArch64SelectionDAGInfo::verifyTargetNode(const SelectionDAG &DAG,
                                                const SDNode *N) const {
-  SelectionDAGGenTargetInfo::verifyTargetNode(DAG, N);
+  //  SelectionDAGGenTargetInfo::verifyTargetNode(DAG, N);
 
 #ifndef NDEBUG
   // Some additional checks not yet implemented by verifyTargetNode.

>From 00ddddafaed3c5550750f1cc0e3251dc609df8b7 Mon Sep 17 00:00:00 2001
From: "Pan, Tao" <tao.pan at intel.com>
Date: Mon, 29 Sep 2025 15:21:25 +0800
Subject: [PATCH 2/7] Change DAG.getRegister to DAG.getCopyFromReg

---
 llvm/lib/Target/AArch64/AArch64ISelLowering.cpp | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
index a722b5f42fa65..59f5cca45fb45 100644
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -29101,9 +29101,10 @@ bool AArch64TargetLowering::useStackGuardXorFP() const { return true; }
 SDValue AArch64TargetLowering::emitStackGuardXorFP(SelectionDAG &DAG,
                                                    SDValue Val,
                                                    const SDLoc &DL) const {
-  return DAG.getNode(
-      ISD::XOR, DL, Val.getValueType(), Val,
-      DAG.getRegister(getStackPointerRegisterToSaveRestore(), MVT::i64));
+  return DAG.getNode(ISD::XOR, DL, Val.getValueType(), Val,
+                     DAG.getCopyFromReg(DAG.getEntryNode(), DL,
+                                        getStackPointerRegisterToSaveRestore(),
+                                        MVT::i64));
 }
 
 unsigned AArch64TargetLowering::combineRepeatedFPDivisors() const {

>From 5c230aecd2bd8c18f0f1ccae16e75a15f62c9b32 Mon Sep 17 00:00:00 2001
From: "Pan, Tao" <tao.pan at intel.com>
Date: Fri, 10 Oct 2025 08:58:21 +0800
Subject: [PATCH 3/7] Fix failed tests

---
 .../Target/AArch64/AArch64ISelLowering.cpp    | 11 +++++--
 llvm/test/CodeGen/AArch64/mingw-refptr.ll     | 30 +++++++++++--------
 .../CodeGen/AArch64/stack-protector-target.ll | 12 ++++----
 3 files changed, 33 insertions(+), 20 deletions(-)

diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
index 59f5cca45fb45..2ce9282c4156b 100644
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -29093,10 +29093,17 @@ void AArch64TargetLowering::ReplaceNodeResults(
 bool AArch64TargetLowering::useLoadStackGuardNode(const Module &M) const {
   if (Subtarget->isTargetAndroid() || Subtarget->isTargetFuchsia())
     return TargetLowering::useLoadStackGuardNode(M);
-  return false;
+  return !Subtarget->getTargetTriple().isOSMSVCRT() ||
+         Subtarget->isTargetMachO() ||
+         getTargetMachine().Options.EnableGlobalISel;
 }
 
-bool AArch64TargetLowering::useStackGuardXorFP() const { return true; }
+bool AArch64TargetLowering::useStackGuardXorFP() const {
+  // Currently only MSVC CRTs XOR the frame pointer into the stack guard value.
+  return Subtarget->getTargetTriple().isOSMSVCRT() &&
+         !Subtarget->isTargetMachO() &&
+         !getTargetMachine().Options.EnableGlobalISel;
+}
 
 SDValue AArch64TargetLowering::emitStackGuardXorFP(SelectionDAG &DAG,
                                                    SDValue Val,
diff --git a/llvm/test/CodeGen/AArch64/mingw-refptr.ll b/llvm/test/CodeGen/AArch64/mingw-refptr.ll
index cc9fac0506ff5..445888845f001 100644
--- a/llvm/test/CodeGen/AArch64/mingw-refptr.ll
+++ b/llvm/test/CodeGen/AArch64/mingw-refptr.ll
@@ -1,6 +1,6 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
 ; RUN: llc < %s -mtriple=aarch64-w64-mingw32 | FileCheck %s --check-prefixes=CHECK,CHECK-SD
-; RUN: llc < %s -mtriple=aarch64-w64-mingw32 -global-isel | FileCheck %s --check-prefixes=CHECK,CHECK-GI
+; RUN: llc < %s -mtriple=aarch64-w64-mingw32 -global-isel | FileCheck %s --check-prefixes=CHECK-GI
 
 @var = external local_unnamed_addr global i32, align 4
 @dsolocalvar = external dso_local local_unnamed_addr global i32, align 4
@@ -82,25 +82,31 @@ define dso_local void @sspFunc() #0 {
 ; CHECK-NEXT:  // %bb.0: // %entry
 ; CHECK-NEXT:    sub sp, sp, #32
 ; CHECK-NEXT:    .seh_stackalloc 32
-; CHECK-NEXT:    str x30, [sp, #16] // 8-byte Folded Spill
-; CHECK-NEXT:    .seh_save_reg x30, 16
+; CHECK-NEXT:    str x19, [sp, #16] // 8-byte Folded Spill
+; CHECK-NEXT:    .seh_save_reg	x19, 16
+; CHECK-NEXT:    str x30, [sp, #24]                  // 8-byte Folded Spill
+; CHECK-NEXT:    .seh_save_reg x30, 24
 ; CHECK-NEXT:    .seh_endprologue
-; CHECK-NEXT:    adrp x8, .refptr.__stack_chk_guard
+; CHECK-NEXT:    adrp x19, .refptr.__stack_chk_guard
+; CHECK-NEXT:    mov x9, sp
 ; CHECK-NEXT:    add x0, sp, #7
-; CHECK-NEXT:    ldr x8, [x8, :lo12:.refptr.__stack_chk_guard]
-; CHECK-NEXT:    ldr x8, [x8]
+; CHECK-NEXT:    ldr x19, [x19, :lo12:.refptr.__stack_chk_guard]
+; CHECK-NEXT:    ldr x8, [x19]
+; CHECK-NEXT:    eor x8, x8, x9
 ; CHECK-NEXT:    str x8, [sp, #8]
 ; CHECK-NEXT:    bl ptrUser
-; CHECK-NEXT:    adrp x8, .refptr.__stack_chk_guard
-; CHECK-NEXT:    ldr x8, [x8, :lo12:.refptr.__stack_chk_guard]
 ; CHECK-NEXT:    ldr x9, [sp, #8]
-; CHECK-NEXT:    ldr x8, [x8]
-; CHECK-NEXT:    cmp x8, x9
+; CHECK-NEXT:    mov x8, sp
+; CHECK-NEXT:    ldr x10, [x19]
+; CHECK-NEXT:    eor x8, x9, x8
+; CHECK-NEXT:    cmp x10, x8
 ; CHECK-NEXT:    b.ne .LBB6_2
 ; CHECK-NEXT:  // %bb.1: // %entry
 ; CHECK-NEXT:    .seh_startepilogue
-; CHECK-NEXT:    ldr x30, [sp, #16] // 8-byte Folded Reload
-; CHECK-NEXT:    .seh_save_reg x30, 16
+; CHECK-NEXT:    ldr x30, [sp, #24] // 8-byte Folded Reload
+; CHECK-NEXT:    .seh_save_reg x30, 24
+; CHECK-NEXT:    ldr x19, [sp, #16]                  // 8-byte Folded Reload
+; CHECK-NEXT:    .seh_save_reg	x19, 16
 ; CHECK-NEXT:    add sp, sp, #32
 ; CHECK-NEXT:    .seh_stackalloc 32
 ; CHECK-NEXT:    .seh_endepilogue
diff --git a/llvm/test/CodeGen/AArch64/stack-protector-target.ll b/llvm/test/CodeGen/AArch64/stack-protector-target.ll
index b1ddd1d0d160f..9940a4d75d09b 100644
--- a/llvm/test/CodeGen/AArch64/stack-protector-target.ll
+++ b/llvm/test/CodeGen/AArch64/stack-protector-target.ll
@@ -29,16 +29,16 @@ declare void @_Z7CapturePi(ptr)
 ; FUCHSIA-AARCH64-COMMON: ldr [[D:.*]], [sp,
 ; FUCHSIA-AARCH64-COMMON: cmp [[C]], [[D]]
 
-; WINDOWS-AARCH64: adrp x8, __security_cookie
-; WINDOWS-AARCH64: ldr x8, [x8, :lo12:__security_cookie]
+; WINDOWS-AARCH64: adrp x19, __security_cookie
+; WINDOWS-AARCH64: ldr x8, [x19, :lo12:__security_cookie]
 ; WINDOWS-AARCH64: str x8, [sp, #8]
 ; WINDOWS-AARCH64: bl  _Z7CapturePi
-; WINDOWS-AARCH64: ldr x0, [sp, #8]
+; WINDOWS-AARCH64: ldr x8, [sp, #8]
 ; WINDOWS-AARCH64: bl  __security_check_cookie
 
-; WINDOWS-ARM64EC: adrp x8, __security_cookie
-; WINDOWS-ARM64EC: ldr x8, [x8, :lo12:__security_cookie]
+; WINDOWS-ARM64EC: adrp x19, __security_cookie
+; WINDOWS-ARM64EC: ldr x8, [x19, :lo12:__security_cookie]
 ; WINDOWS-ARM64EC: str x8, [sp, #8]
 ; WINDOWS-ARM64EC: bl "#_Z7CapturePi"
-; WINDOWS-ARM64EC: ldr x0, [sp, #8]
+; WINDOWS-ARM64EC: ldr x8, [sp, #8]
 ; WINDOWS-ARM64EC: bl "#__security_check_cookie_arm64ec"

>From 12ded1eb51a757fee5229186589fc00b7cb38a76 Mon Sep 17 00:00:00 2001
From: "Pan, Tao" <tao.pan at intel.com>
Date: Thu, 16 Oct 2025 09:09:33 +0800
Subject: [PATCH 4/7] Add the EOR instruction in
 AArch64InstrInfo::expandPostRAPseudo

---
 .../Target/AArch64/AArch64ISelLowering.cpp    | 20 +------------
 llvm/lib/Target/AArch64/AArch64ISelLowering.h |  3 --
 llvm/lib/Target/AArch64/AArch64InstrInfo.cpp  |  8 +++++
 .../AArch64/AArch64SelectionDAGInfo.cpp       |  2 +-
 llvm/test/CodeGen/AArch64/mingw-refptr.ll     | 30 ++++++++-----------
 .../CodeGen/AArch64/stack-protector-target.ll | 14 +++++----
 6 files changed, 30 insertions(+), 47 deletions(-)

diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
index 2ce9282c4156b..60aa61e993b26 100644
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -29093,25 +29093,7 @@ void AArch64TargetLowering::ReplaceNodeResults(
 bool AArch64TargetLowering::useLoadStackGuardNode(const Module &M) const {
   if (Subtarget->isTargetAndroid() || Subtarget->isTargetFuchsia())
     return TargetLowering::useLoadStackGuardNode(M);
-  return !Subtarget->getTargetTriple().isOSMSVCRT() ||
-         Subtarget->isTargetMachO() ||
-         getTargetMachine().Options.EnableGlobalISel;
-}
-
-bool AArch64TargetLowering::useStackGuardXorFP() const {
-  // Currently only MSVC CRTs XOR the frame pointer into the stack guard value.
-  return Subtarget->getTargetTriple().isOSMSVCRT() &&
-         !Subtarget->isTargetMachO() &&
-         !getTargetMachine().Options.EnableGlobalISel;
-}
-
-SDValue AArch64TargetLowering::emitStackGuardXorFP(SelectionDAG &DAG,
-                                                   SDValue Val,
-                                                   const SDLoc &DL) const {
-  return DAG.getNode(ISD::XOR, DL, Val.getValueType(), Val,
-                     DAG.getCopyFromReg(DAG.getEntryNode(), DL,
-                                        getStackPointerRegisterToSaveRestore(),
-                                        MVT::i64));
+  return true;
 }
 
 unsigned AArch64TargetLowering::combineRepeatedFPDivisors() const {
diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.h b/llvm/lib/Target/AArch64/AArch64ISelLowering.h
index fe6ccdc5947fe..2cb8ed29f252a 100644
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.h
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.h
@@ -358,9 +358,6 @@ class AArch64TargetLowering : public TargetLowering {
   shouldExpandAtomicCmpXchgInIR(AtomicCmpXchgInst *AI) const override;
 
   bool useLoadStackGuardNode(const Module &M) const override;
-  bool useStackGuardXorFP() const override;
-  SDValue emitStackGuardXorFP(SelectionDAG &DAG, SDValue Val,
-                              const SDLoc &DL) const override;
   TargetLoweringBase::LegalizeTypeAction
   getPreferredVectorAction(MVT VT) const override;
 
diff --git a/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp b/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp
index 457e5402e0f46..ed1d9639500df 100644
--- a/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp
+++ b/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp
@@ -2310,6 +2310,14 @@ bool AArch64InstrInfo::expandPostRAPseudo(MachineInstr &MI) const {
           .addGlobalAddress(GV, 0, LoFlags)
           .addMemOperand(*MI.memoperands_begin());
     }
+    if (Subtarget.getTargetTriple().isOSMSVCRT() &&
+        !Subtarget.getTargetLowering()
+             ->getTargetMachine()
+             .Options.EnableGlobalISel) {
+      BuildMI(MBB, MI, DL, get(AArch64::EORWrr), Reg)
+          .addReg(Reg, RegState::Kill)
+          .addReg(AArch64::SP);
+    }
   }
 
   MBB.erase(MI);
diff --git a/llvm/lib/Target/AArch64/AArch64SelectionDAGInfo.cpp b/llvm/lib/Target/AArch64/AArch64SelectionDAGInfo.cpp
index 163de52386221..d3b1aa621b61a 100644
--- a/llvm/lib/Target/AArch64/AArch64SelectionDAGInfo.cpp
+++ b/llvm/lib/Target/AArch64/AArch64SelectionDAGInfo.cpp
@@ -32,7 +32,7 @@ AArch64SelectionDAGInfo::AArch64SelectionDAGInfo()
 
 void AArch64SelectionDAGInfo::verifyTargetNode(const SelectionDAG &DAG,
                                                const SDNode *N) const {
-  //  SelectionDAGGenTargetInfo::verifyTargetNode(DAG, N);
+  SelectionDAGGenTargetInfo::verifyTargetNode(DAG, N);
 
 #ifndef NDEBUG
   // Some additional checks not yet implemented by verifyTargetNode.
diff --git a/llvm/test/CodeGen/AArch64/mingw-refptr.ll b/llvm/test/CodeGen/AArch64/mingw-refptr.ll
index 445888845f001..cc9fac0506ff5 100644
--- a/llvm/test/CodeGen/AArch64/mingw-refptr.ll
+++ b/llvm/test/CodeGen/AArch64/mingw-refptr.ll
@@ -1,6 +1,6 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
 ; RUN: llc < %s -mtriple=aarch64-w64-mingw32 | FileCheck %s --check-prefixes=CHECK,CHECK-SD
-; RUN: llc < %s -mtriple=aarch64-w64-mingw32 -global-isel | FileCheck %s --check-prefixes=CHECK-GI
+; RUN: llc < %s -mtriple=aarch64-w64-mingw32 -global-isel | FileCheck %s --check-prefixes=CHECK,CHECK-GI
 
 @var = external local_unnamed_addr global i32, align 4
 @dsolocalvar = external dso_local local_unnamed_addr global i32, align 4
@@ -82,31 +82,25 @@ define dso_local void @sspFunc() #0 {
 ; CHECK-NEXT:  // %bb.0: // %entry
 ; CHECK-NEXT:    sub sp, sp, #32
 ; CHECK-NEXT:    .seh_stackalloc 32
-; CHECK-NEXT:    str x19, [sp, #16] // 8-byte Folded Spill
-; CHECK-NEXT:    .seh_save_reg	x19, 16
-; CHECK-NEXT:    str x30, [sp, #24]                  // 8-byte Folded Spill
-; CHECK-NEXT:    .seh_save_reg x30, 24
+; CHECK-NEXT:    str x30, [sp, #16] // 8-byte Folded Spill
+; CHECK-NEXT:    .seh_save_reg x30, 16
 ; CHECK-NEXT:    .seh_endprologue
-; CHECK-NEXT:    adrp x19, .refptr.__stack_chk_guard
-; CHECK-NEXT:    mov x9, sp
+; CHECK-NEXT:    adrp x8, .refptr.__stack_chk_guard
 ; CHECK-NEXT:    add x0, sp, #7
-; CHECK-NEXT:    ldr x19, [x19, :lo12:.refptr.__stack_chk_guard]
-; CHECK-NEXT:    ldr x8, [x19]
-; CHECK-NEXT:    eor x8, x8, x9
+; CHECK-NEXT:    ldr x8, [x8, :lo12:.refptr.__stack_chk_guard]
+; CHECK-NEXT:    ldr x8, [x8]
 ; CHECK-NEXT:    str x8, [sp, #8]
 ; CHECK-NEXT:    bl ptrUser
+; CHECK-NEXT:    adrp x8, .refptr.__stack_chk_guard
+; CHECK-NEXT:    ldr x8, [x8, :lo12:.refptr.__stack_chk_guard]
 ; CHECK-NEXT:    ldr x9, [sp, #8]
-; CHECK-NEXT:    mov x8, sp
-; CHECK-NEXT:    ldr x10, [x19]
-; CHECK-NEXT:    eor x8, x9, x8
-; CHECK-NEXT:    cmp x10, x8
+; CHECK-NEXT:    ldr x8, [x8]
+; CHECK-NEXT:    cmp x8, x9
 ; CHECK-NEXT:    b.ne .LBB6_2
 ; CHECK-NEXT:  // %bb.1: // %entry
 ; CHECK-NEXT:    .seh_startepilogue
-; CHECK-NEXT:    ldr x30, [sp, #24] // 8-byte Folded Reload
-; CHECK-NEXT:    .seh_save_reg x30, 24
-; CHECK-NEXT:    ldr x19, [sp, #16]                  // 8-byte Folded Reload
-; CHECK-NEXT:    .seh_save_reg	x19, 16
+; CHECK-NEXT:    ldr x30, [sp, #16] // 8-byte Folded Reload
+; CHECK-NEXT:    .seh_save_reg x30, 16
 ; CHECK-NEXT:    add sp, sp, #32
 ; CHECK-NEXT:    .seh_stackalloc 32
 ; CHECK-NEXT:    .seh_endepilogue
diff --git a/llvm/test/CodeGen/AArch64/stack-protector-target.ll b/llvm/test/CodeGen/AArch64/stack-protector-target.ll
index 9940a4d75d09b..59045190c8892 100644
--- a/llvm/test/CodeGen/AArch64/stack-protector-target.ll
+++ b/llvm/test/CodeGen/AArch64/stack-protector-target.ll
@@ -29,16 +29,18 @@ declare void @_Z7CapturePi(ptr)
 ; FUCHSIA-AARCH64-COMMON: ldr [[D:.*]], [sp,
 ; FUCHSIA-AARCH64-COMMON: cmp [[C]], [[D]]
 
-; WINDOWS-AARCH64: adrp x19, __security_cookie
-; WINDOWS-AARCH64: ldr x8, [x19, :lo12:__security_cookie]
+; WINDOWS-AARCH64: adrp x8, __security_cookie
+; WINDOWS-AARCH64: ldr x8, [x8, :lo12:__security_cookie]
+; WINDOWS-AARCH64: eor x8, x8, sp
 ; WINDOWS-AARCH64: str x8, [sp, #8]
 ; WINDOWS-AARCH64: bl  _Z7CapturePi
-; WINDOWS-AARCH64: ldr x8, [sp, #8]
+; WINDOWS-AARCH64: ldr x0, [sp, #8]
 ; WINDOWS-AARCH64: bl  __security_check_cookie
 
-; WINDOWS-ARM64EC: adrp x19, __security_cookie
-; WINDOWS-ARM64EC: ldr x8, [x19, :lo12:__security_cookie]
+; WINDOWS-ARM64EC: adrp x8, __security_cookie
+; WINDOWS-ARM64EC: ldr x8, [x8, :lo12:__security_cookie]
+; WINDOWS-ARM64EC: eor x8, x8, sp
 ; WINDOWS-ARM64EC: str x8, [sp, #8]
 ; WINDOWS-ARM64EC: bl "#_Z7CapturePi"
-; WINDOWS-ARM64EC: ldr x8, [sp, #8]
+; WINDOWS-ARM64EC: ldr x0, [sp, #8]
 ; WINDOWS-ARM64EC: bl "#__security_check_cookie_arm64ec"

>From 23fbbbbf5e52dcdb04774f2d1041eba42df7cd1a Mon Sep 17 00:00:00 2001
From: "Pan, Tao" <tao.pan at intel.com>
Date: Thu, 16 Oct 2025 14:17:29 +0800
Subject: [PATCH 5/7] Add the eor instruction to any code model

---
 llvm/lib/Target/AArch64/AArch64InstrInfo.cpp | 17 +++++++++--------
 llvm/test/CodeGen/AArch64/mingw-refptr.ll    |  4 +++-
 2 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp b/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp
index ed1d9639500df..8bc65f8b4c575 100644
--- a/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp
+++ b/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp
@@ -2310,14 +2310,15 @@ bool AArch64InstrInfo::expandPostRAPseudo(MachineInstr &MI) const {
           .addGlobalAddress(GV, 0, LoFlags)
           .addMemOperand(*MI.memoperands_begin());
     }
-    if (Subtarget.getTargetTriple().isOSMSVCRT() &&
-        !Subtarget.getTargetLowering()
-             ->getTargetMachine()
-             .Options.EnableGlobalISel) {
-      BuildMI(MBB, MI, DL, get(AArch64::EORWrr), Reg)
-          .addReg(Reg, RegState::Kill)
-          .addReg(AArch64::SP);
-    }
+  }
+  // To match MSVC
+  if (Subtarget.getTargetTriple().isOSMSVCRT() &&
+      !Subtarget.getTargetLowering()
+           ->getTargetMachine()
+           .Options.EnableGlobalISel) {
+    BuildMI(MBB, MI, DL, get(AArch64::EORWrr), Reg)
+        .addReg(Reg, RegState::Kill)
+        .addReg(AArch64::SP);
   }
 
   MBB.erase(MI);
diff --git a/llvm/test/CodeGen/AArch64/mingw-refptr.ll b/llvm/test/CodeGen/AArch64/mingw-refptr.ll
index cc9fac0506ff5..fb95d945b8e22 100644
--- a/llvm/test/CodeGen/AArch64/mingw-refptr.ll
+++ b/llvm/test/CodeGen/AArch64/mingw-refptr.ll
@@ -1,6 +1,6 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
 ; RUN: llc < %s -mtriple=aarch64-w64-mingw32 | FileCheck %s --check-prefixes=CHECK,CHECK-SD
-; RUN: llc < %s -mtriple=aarch64-w64-mingw32 -global-isel | FileCheck %s --check-prefixes=CHECK,CHECK-GI
+; RUN: llc < %s -mtriple=aarch64-w64-mingw32 -global-isel | FileCheck %s --check-prefixes=CHECK-GI
 
 @var = external local_unnamed_addr global i32, align 4
 @dsolocalvar = external dso_local local_unnamed_addr global i32, align 4
@@ -89,12 +89,14 @@ define dso_local void @sspFunc() #0 {
 ; CHECK-NEXT:    add x0, sp, #7
 ; CHECK-NEXT:    ldr x8, [x8, :lo12:.refptr.__stack_chk_guard]
 ; CHECK-NEXT:    ldr x8, [x8]
+; CHECK-NEXT:    eor x8, x8, sp
 ; CHECK-NEXT:    str x8, [sp, #8]
 ; CHECK-NEXT:    bl ptrUser
 ; CHECK-NEXT:    adrp x8, .refptr.__stack_chk_guard
 ; CHECK-NEXT:    ldr x8, [x8, :lo12:.refptr.__stack_chk_guard]
 ; CHECK-NEXT:    ldr x9, [sp, #8]
 ; CHECK-NEXT:    ldr x8, [x8]
+; CHECK-NEXT:    eor x8, x8, sp
 ; CHECK-NEXT:    cmp x8, x9
 ; CHECK-NEXT:    b.ne .LBB6_2
 ; CHECK-NEXT:  // %bb.1: // %entry

>From c61707ae9c8a92770b66b28f4a8b3bd55d3708bc Mon Sep 17 00:00:00 2001
From: "Pan, Tao" <tao.pan at intel.com>
Date: Fri, 17 Oct 2025 09:45:22 +0800
Subject: [PATCH 6/7] Add the eor instruction in the failure BB

---
 llvm/include/llvm/CodeGen/TargetLowering.h    |  2 +-
 .../SelectionDAG/SelectionDAGBuilder.cpp      |  6 +++---
 .../Target/AArch64/AArch64ISelLowering.cpp    | 19 +++++++++++++++++++
 llvm/lib/Target/AArch64/AArch64ISelLowering.h |  3 +++
 llvm/lib/Target/X86/X86ISelLowering.cpp       |  3 ++-
 llvm/lib/Target/X86/X86ISelLowering.h         |  5 ++---
 .../CodeGen/AArch64/stack-protector-target.ll |  8 ++++++--
 7 files changed, 36 insertions(+), 10 deletions(-)

diff --git a/llvm/include/llvm/CodeGen/TargetLowering.h b/llvm/include/llvm/CodeGen/TargetLowering.h
index 1920b98c8a1ef..3dbae93c76efd 100644
--- a/llvm/include/llvm/CodeGen/TargetLowering.h
+++ b/llvm/include/llvm/CodeGen/TargetLowering.h
@@ -5798,7 +5798,7 @@ class LLVM_ABI TargetLowering : public TargetLoweringBase {
   virtual bool useLoadStackGuardNode(const Module &M) const { return false; }
 
   virtual SDValue emitStackGuardXorFP(SelectionDAG &DAG, SDValue Val,
-                                      const SDLoc &DL) const {
+                                      const SDLoc &DL, bool FailureBB) const {
     llvm_unreachable("not implemented for this target");
   }
 
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index a52265055c88a..d12a46ebfe66c 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -3129,7 +3129,7 @@ void SelectionDAGBuilder::visitSPDescriptorParent(StackProtectorDescriptor &SPD,
       MachineMemOperand::MOVolatile);
 
   if (TLI.useStackGuardXorFP())
-    GuardVal = TLI.emitStackGuardXorFP(DAG, GuardVal, dl);
+    GuardVal = TLI.emitStackGuardXorFP(DAG, GuardVal, dl, false);
 
   // If we're using function-based instrumentation, call the guard check
   // function
@@ -3238,7 +3238,7 @@ void SelectionDAGBuilder::visitSPDescriptorFailure(
         MachineMemOperand::MOVolatile);
 
     if (TLI.useStackGuardXorFP())
-      GuardVal = TLI.emitStackGuardXorFP(DAG, GuardVal, dl);
+      GuardVal = TLI.emitStackGuardXorFP(DAG, GuardVal, dl, true);
 
     // The target provides a guard check function to validate the guard value.
     // Generate a call to that function with the content of the guard slot as
@@ -7381,7 +7381,7 @@ void SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I,
                         MachineMemOperand::MOVolatile);
     }
     if (TLI.useStackGuardXorFP())
-      Res = TLI.emitStackGuardXorFP(DAG, Res, sdl);
+      Res = TLI.emitStackGuardXorFP(DAG, Res, sdl, false);
     DAG.setRoot(Chain);
     setValue(&I, Res);
     return;
diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
index 60aa61e993b26..a8e98d92771a2 100644
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -29096,6 +29096,25 @@ bool AArch64TargetLowering::useLoadStackGuardNode(const Module &M) const {
   return true;
 }
 
+bool AArch64TargetLowering::useStackGuardXorFP() const {
+  // Currently only MSVC CRTs XOR the frame pointer into the stack guard value.
+  return Subtarget->getTargetTriple().isOSMSVCRT() &&
+         !Subtarget->isTargetMachO() &&
+         !getTargetMachine().Options.EnableGlobalISel;
+}
+
+SDValue AArch64TargetLowering::emitStackGuardXorFP(SelectionDAG &DAG,
+                                                   SDValue Val, const SDLoc &DL,
+                                                   bool FailureBB) const {
+  if (FailureBB) {
+    return DAG.getNode(
+        ISD::XOR, DL, Val.getValueType(), Val,
+        DAG.getCopyFromReg(DAG.getEntryNode(), DL,
+                           getStackPointerRegisterToSaveRestore(), MVT::i64));
+  }
+  return Val;
+}
+
 unsigned AArch64TargetLowering::combineRepeatedFPDivisors() const {
   // Combine multiple FDIVs with the same divisor into multiple FMULs by the
   // reciprocal if there are three or more FDIVs.
diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.h b/llvm/lib/Target/AArch64/AArch64ISelLowering.h
index 2cb8ed29f252a..405a0103f1944 100644
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.h
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.h
@@ -358,6 +358,9 @@ class AArch64TargetLowering : public TargetLowering {
   shouldExpandAtomicCmpXchgInIR(AtomicCmpXchgInst *AI) const override;
 
   bool useLoadStackGuardNode(const Module &M) const override;
+  bool useStackGuardXorFP() const override;
+  SDValue emitStackGuardXorFP(SelectionDAG &DAG, SDValue Val, const SDLoc &DL,
+                              bool FailureBB) const override;
   TargetLoweringBase::LegalizeTypeAction
   getPreferredVectorAction(MVT VT) const override;
 
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index 5785440a20e43..4420cf628962a 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -2739,7 +2739,8 @@ bool X86TargetLowering::useStackGuardXorFP() const {
 }
 
 SDValue X86TargetLowering::emitStackGuardXorFP(SelectionDAG &DAG, SDValue Val,
-                                               const SDLoc &DL) const {
+                                               const SDLoc &DL,
+                                               bool FailureBB) const {
   EVT PtrTy = getPointerTy(DAG.getDataLayout());
   unsigned XorOp = Subtarget.is64Bit() ? X86::XOR64_FP : X86::XOR32_FP;
   MachineSDNode *Node = DAG.getMachineNode(XorOp, DL, PtrTy, Val);
diff --git a/llvm/lib/Target/X86/X86ISelLowering.h b/llvm/lib/Target/X86/X86ISelLowering.h
index b7151f65942b4..752b94520c4c4 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.h
+++ b/llvm/lib/Target/X86/X86ISelLowering.h
@@ -1592,9 +1592,8 @@ namespace llvm {
     bool useLoadStackGuardNode(const Module &M) const override;
     bool useStackGuardXorFP() const override;
     void insertSSPDeclarations(Module &M) const override;
-    SDValue emitStackGuardXorFP(SelectionDAG &DAG, SDValue Val,
-                                const SDLoc &DL) const override;
-
+    SDValue emitStackGuardXorFP(SelectionDAG &DAG, SDValue Val, const SDLoc &DL,
+                                bool FailureBB) const override;
 
     /// Return true if the target stores SafeStack pointer at a fixed offset in
     /// some non-standard address space, and populates the address space and
diff --git a/llvm/test/CodeGen/AArch64/stack-protector-target.ll b/llvm/test/CodeGen/AArch64/stack-protector-target.ll
index 59045190c8892..201950a6355a3 100644
--- a/llvm/test/CodeGen/AArch64/stack-protector-target.ll
+++ b/llvm/test/CodeGen/AArch64/stack-protector-target.ll
@@ -34,7 +34,9 @@ declare void @_Z7CapturePi(ptr)
 ; WINDOWS-AARCH64: eor x8, x8, sp
 ; WINDOWS-AARCH64: str x8, [sp, #8]
 ; WINDOWS-AARCH64: bl  _Z7CapturePi
-; WINDOWS-AARCH64: ldr x0, [sp, #8]
+; WINDOWS-AARCH64: ldr x8, [sp, #8]
+; WINDOWS-AARCH64: mov x9, sp
+; WINDOWS-AARCH64: eor x0, x8, x9
 ; WINDOWS-AARCH64: bl  __security_check_cookie
 
 ; WINDOWS-ARM64EC: adrp x8, __security_cookie
@@ -42,5 +44,7 @@ declare void @_Z7CapturePi(ptr)
 ; WINDOWS-ARM64EC: eor x8, x8, sp
 ; WINDOWS-ARM64EC: str x8, [sp, #8]
 ; WINDOWS-ARM64EC: bl "#_Z7CapturePi"
-; WINDOWS-ARM64EC: ldr x0, [sp, #8]
+; WINDOWS-ARM64EC: ldr x8, [sp, #8]
+; WINDOWS-ARM64EC: mov x9, sp
+; WINDOWS-ARM64EC: eor x0, x8, x9
 ; WINDOWS-ARM64EC: bl "#__security_check_cookie_arm64ec"

>From 2b02cb2b8d25c2ec222536d609f8cc4e40d24699 Mon Sep 17 00:00:00 2001
From: "Pan, Tao" <tao.pan at intel.com>
Date: Tue, 21 Oct 2025 09:17:57 +0800
Subject: [PATCH 7/7] Remove the isTargetMachO() check and change EORWrr to
 EORXrr

---
 llvm/lib/Target/AArch64/AArch64ISelLowering.cpp | 1 -
 llvm/lib/Target/AArch64/AArch64InstrInfo.cpp    | 2 +-
 2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
index a8e98d92771a2..37b9c01d730d3 100644
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -29099,7 +29099,6 @@ bool AArch64TargetLowering::useLoadStackGuardNode(const Module &M) const {
 bool AArch64TargetLowering::useStackGuardXorFP() const {
   // Currently only MSVC CRTs XOR the frame pointer into the stack guard value.
   return Subtarget->getTargetTriple().isOSMSVCRT() &&
-         !Subtarget->isTargetMachO() &&
          !getTargetMachine().Options.EnableGlobalISel;
 }
 
diff --git a/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp b/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp
index 8bc65f8b4c575..312c159748cda 100644
--- a/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp
+++ b/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp
@@ -2316,7 +2316,7 @@ bool AArch64InstrInfo::expandPostRAPseudo(MachineInstr &MI) const {
       !Subtarget.getTargetLowering()
            ->getTargetMachine()
            .Options.EnableGlobalISel) {
-    BuildMI(MBB, MI, DL, get(AArch64::EORWrr), Reg)
+    BuildMI(MBB, MI, DL, get(AArch64::EORXrr), Reg)
         .addReg(Reg, RegState::Kill)
         .addReg(AArch64::SP);
   }



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