From 704ca6ef7fac8f85ab76a9b934fec3cd65a5230d Mon Sep 17 00:00:00 2001
From: Matt Morehouse <mascasa@google.com>
Date: Wed, 24 Mar 2021 16:17:38 -0700
Subject: [PATCH] Revert "[HWASan] Use page aliasing on x86_64."

This reverts commit 63f73c3eb9716256ab8dbb868e16d08a88636cba due to
breakage on aarch64 without TBI.
---
 .../Instrumentation/HWAddressSanitizer.cpp    |  3 +--
 .../HWAddressSanitizer/X86/atomic.ll          | 10 ++++++--
 .../HWAddressSanitizer/X86/basic.ll           | 25 +++++++++++++++----
 .../HWAddressSanitizer/X86/kernel.ll          |  5 +++-
 .../HWAddressSanitizer/X86/with-calls.ll      | 20 ++++++++++++---
 5 files changed, 49 insertions(+), 14 deletions(-)

diff --git a/lib/Transforms/Instrumentation/HWAddressSanitizer.cpp b/lib/Transforms/Instrumentation/HWAddressSanitizer.cpp
index 07892bdc854..1c368e7cd13 100644
--- a/lib/Transforms/Instrumentation/HWAddressSanitizer.cpp
+++ b/lib/Transforms/Instrumentation/HWAddressSanitizer.cpp
@@ -708,7 +708,7 @@ static size_t TypeSizeToSizeIndex(uint32_t TypeSize) {
 }
 
 void HWAddressSanitizer::untagPointerOperand(Instruction *I, Value *Addr) {
-  if (TargetTriple.isAArch64() || TargetTriple.getArch() == Triple::x86_64)
+  if (TargetTriple.isAArch64())
     return;
 
   IRBuilder<> IRB(I);
@@ -1004,7 +1004,6 @@ Value *HWAddressSanitizer::tagPointer(IRBuilder<> &IRB, Type *Ty,
 
 // Remove tag from an address.
 Value *HWAddressSanitizer::untagPointer(IRBuilder<> &IRB, Value *PtrLong) {
-  assert(!UsePageAliases);
   Value *UntaggedPtrLong;
   if (CompileKernel) {
     // Kernel addresses have 0xFF in the most significant byte.
diff --git a/test/Instrumentation/HWAddressSanitizer/X86/atomic.ll b/test/Instrumentation/HWAddressSanitizer/X86/atomic.ll
index e85fc70fecf..ce2c187cf03 100644
--- a/test/Instrumentation/HWAddressSanitizer/X86/atomic.ll
+++ b/test/Instrumentation/HWAddressSanitizer/X86/atomic.ll
@@ -11,7 +11,10 @@ define void @atomicrmw(i64* %ptr) sanitize_hwaddress {
 
 ; CHECK: call void @__hwasan_store8(i64 %[[A]])
 
-; CHECK: atomicrmw add i64* %ptr, i64 1 seq_cst
+; CHECK: %[[A:[^ ]*]] = ptrtoint i64* %ptr to i64
+; CHECK: %[[UNTAGGED:[^ ]*]] = and i64 %[[A]], 72057594037927935
+; CHECK: %[[UNTAGGED_PTR:[^ ]*]] = inttoptr i64 %[[UNTAGGED]] to i64*
+; CHECK: atomicrmw add i64* %[[UNTAGGED_PTR]], i64 1 seq_cst
 ; CHECK: ret void
 
 entry:
@@ -25,7 +28,10 @@ define void @cmpxchg(i64* %ptr, i64 %compare_to, i64 %new_value) sanitize_hwaddr
 
 ; CHECK: call void @__hwasan_store8(i64 %[[A]])
 
-; CHECK: cmpxchg i64* %ptr, i64 %compare_to, i64 %new_value seq_cst seq_cst
+; CHECK: %[[A:[^ ]*]] = ptrtoint i64* %ptr to i64
+; CHECK: %[[UNTAGGED:[^ ]*]] = and i64 %[[A]], 72057594037927935
+; CHECK: %[[UNTAGGED_PTR:[^ ]*]] = inttoptr i64 %[[UNTAGGED]] to i64*
+; CHECK: cmpxchg i64* %[[UNTAGGED_PTR]], i64 %compare_to, i64 %new_value seq_cst seq_cst
 ; CHECK: ret void
 
 entry:
diff --git a/test/Instrumentation/HWAddressSanitizer/X86/basic.ll b/test/Instrumentation/HWAddressSanitizer/X86/basic.ll
index 59e73c5f208..e93ebb76625 100644
--- a/test/Instrumentation/HWAddressSanitizer/X86/basic.ll
+++ b/test/Instrumentation/HWAddressSanitizer/X86/basic.ll
@@ -15,7 +15,10 @@ define i8 @test_load8(i8* %a) sanitize_hwaddress {
 ; ABORT: call void @__hwasan_load1(i64 %[[A]])
 ; RECOVER: call void @__hwasan_load1_noabort(i64 %[[A]])
 
-; CHECK: %[[G:[^ ]*]] = load i8, i8* %a, align 4
+; CHECK: %[[A:[^ ]*]] = ptrtoint i8* %a to i64
+; CHECK: %[[UNTAGGED:[^ ]*]] = and i64 %[[A]], 72057594037927935
+; CHECK: %[[UNTAGGED_PTR:[^ ]*]] = inttoptr i64 %[[UNTAGGED]] to i8*
+; CHECK: %[[G:[^ ]*]] = load i8, i8* %[[UNTAGGED_PTR]], align 4
 ; CHECK: ret i8 %[[G]]
 
 entry:
@@ -30,7 +33,10 @@ define i40 @test_load40(i40* %a) sanitize_hwaddress {
 ; ABORT: call void @__hwasan_loadN(i64 %[[A]], i64 5)
 ; RECOVER: call void @__hwasan_loadN_noabort(i64 %[[A]], i64 5)
 
-; CHECK: %[[B:[^ ]*]] = load i40, i40* %a
+; CHECK: %[[A:[^ ]*]] = ptrtoint i40* %a to i64
+; CHECK: %[[UNTAGGED:[^ ]*]] = and i64 %[[A]], 72057594037927935
+; CHECK: %[[UNTAGGED_PTR:[^ ]*]] = inttoptr i64 %[[UNTAGGED]] to i40*
+; CHECK: %[[B:[^ ]*]] = load i40, i40* %[[UNTAGGED_PTR]]
 ; CHECK: ret i40 %[[B]]
 
 entry:
@@ -45,7 +51,10 @@ define void @test_store8(i8* %a, i8 %b) sanitize_hwaddress {
 ; ABORT: call void @__hwasan_store1(i64 %[[A]])
 ; RECOVER: call void @__hwasan_store1_noabort(i64 %[[A]])
 
-; CHECK: store i8 %b, i8* %a, align 4
+; CHECK: %[[A:[^ ]*]] = ptrtoint i8* %a to i64
+; CHECK: %[[UNTAGGED:[^ ]*]] = and i64 %[[A]], 72057594037927935
+; CHECK: %[[UNTAGGED_PTR:[^ ]*]] = inttoptr i64 %[[UNTAGGED]] to i8*
+; CHECK: store i8 %b, i8* %[[UNTAGGED_PTR]], align 4
 ; CHECK: ret void
 
 entry:
@@ -60,7 +69,10 @@ define void @test_store40(i40* %a, i40 %b) sanitize_hwaddress {
 ; ABORT: call void @__hwasan_storeN(i64 %[[A]], i64 5)
 ; RECOVER: call void @__hwasan_storeN_noabort(i64 %[[A]], i64 5)
 
-; CHECK: store i40 %b, i40* %a
+; CHECK: %[[A:[^ ]*]] = ptrtoint i40* %a to i64
+; CHECK: %[[UNTAGGED:[^ ]*]] = and i64 %[[A]], 72057594037927935
+; CHECK: %[[UNTAGGED_PTR:[^ ]*]] = inttoptr i64 %[[UNTAGGED]] to i40*
+; CHECK: store i40 %b, i40* %[[UNTAGGED_PTR]]
 ; CHECK: ret void
 
 entry:
@@ -75,7 +87,10 @@ define void @test_store_unaligned(i64* %a, i64 %b) sanitize_hwaddress {
 ; ABORT: call void @__hwasan_storeN(i64 %[[A]], i64 8)
 ; RECOVER: call void @__hwasan_storeN_noabort(i64 %[[A]], i64 8)
 
-; CHECK: store i64 %b, i64* %a, align 4
+; CHECK: %[[A:[^ ]*]] = ptrtoint i64* %a to i64
+; CHECK: %[[UNTAGGED:[^ ]*]] = and i64 %[[A]], 72057594037927935
+; CHECK: %[[UNTAGGED_PTR:[^ ]*]] = inttoptr i64 %[[UNTAGGED]] to i64*
+; CHECK: store i64 %b, i64* %[[UNTAGGED_PTR]], align 4
 ; CHECK: ret void
 
 entry:
diff --git a/test/Instrumentation/HWAddressSanitizer/X86/kernel.ll b/test/Instrumentation/HWAddressSanitizer/X86/kernel.ll
index 7cea081f6de..66e13daf68f 100644
--- a/test/Instrumentation/HWAddressSanitizer/X86/kernel.ll
+++ b/test/Instrumentation/HWAddressSanitizer/X86/kernel.ll
@@ -18,7 +18,10 @@ define i8 @test_load(i8* %a) sanitize_hwaddress {
 ; ABORT: call void @__hwasan_load1(i64 %[[A]])
 ; RECOVER: call void @__hwasan_load1_noabort(i64 %[[A]])
 
-; CHECK: %[[G:[^ ]*]] = load i8, i8* %a, align 4
+; CHECK: %[[A:[^ ]*]] = ptrtoint i8* %a to i64
+; CHECK: %[[UNTAGGED:[^ ]*]] = or i64 %[[A]], -72057594037927936
+; CHECK: %[[UNTAGGED_PTR:[^ ]*]] = inttoptr i64 %[[UNTAGGED]] to i8*
+; CHECK: %[[G:[^ ]*]] = load i8, i8* %[[UNTAGGED_PTR]], align 4
 ; CHECK: ret i8 %[[G]]
 
 entry:
diff --git a/test/Instrumentation/HWAddressSanitizer/X86/with-calls.ll b/test/Instrumentation/HWAddressSanitizer/X86/with-calls.ll
index 60d2f047b7f..c6fce2fe2ca 100644
--- a/test/Instrumentation/HWAddressSanitizer/X86/with-calls.ll
+++ b/test/Instrumentation/HWAddressSanitizer/X86/with-calls.ll
@@ -13,7 +13,10 @@ define i8 @test_load8(i8* %a) sanitize_hwaddress {
 ; ABORT: call void @__hwasan_load1(i64 %[[A]])
 ; RECOVER: call void @__hwasan_load1_noabort(i64 %[[A]])
 
-; CHECK: %[[B:[^ ]*]] = load i8, i8* %a
+; CHECK: %[[A:[^ ]*]] = ptrtoint i8* %a to i64
+; CHECK: %[[UNTAGGED:[^ ]*]] = and i64 %[[A]], 72057594037927935
+; CHECK: %[[UNTAGGED_PTR:[^ ]*]] = inttoptr i64 %[[UNTAGGED]] to i8*
+; CHECK: %[[B:[^ ]*]] = load i8, i8* %[[UNTAGGED_PTR]]
 ; CHECK: ret i8 %[[B]]
 
 entry:
@@ -28,7 +31,10 @@ define i40 @test_load40(i40* %a) sanitize_hwaddress {
 ; ABORT: call void @__hwasan_loadN(i64 %[[A]], i64 5)
 ; RECOVER: call void @__hwasan_loadN_noabort(i64 %[[A]], i64 5)
 
-; CHECK: %[[B:[^ ]*]] = load i40, i40* %a
+; CHECK: %[[A:[^ ]*]] = ptrtoint i40* %a to i64
+; CHECK: %[[UNTAGGED:[^ ]*]] = and i64 %[[A]], 72057594037927935
+; CHECK: %[[UNTAGGED_PTR:[^ ]*]] = inttoptr i64 %[[UNTAGGED]] to i40*
+; CHECK: %[[B:[^ ]*]] = load i40, i40* %[[UNTAGGED_PTR]]
 ; CHECK: ret i40 %[[B]]
 
 entry:
@@ -43,7 +49,10 @@ define void @test_store8(i8* %a, i8 %b) sanitize_hwaddress {
 ; ABORT: call void @__hwasan_store1(i64 %[[A]])
 ; RECOVER: call void @__hwasan_store1_noabort(i64 %[[A]])
 
-; CHECK: store i8 %b, i8* %a
+; CHECK: %[[A:[^ ]*]] = ptrtoint i8* %a to i64
+; CHECK: %[[UNTAGGED:[^ ]*]] = and i64 %[[A]], 72057594037927935
+; CHECK: %[[UNTAGGED_PTR:[^ ]*]] = inttoptr i64 %[[UNTAGGED]] to i8*
+; CHECK: store i8 %b, i8* %[[UNTAGGED_PTR]]
 ; CHECK: ret void
 
 entry:
@@ -58,7 +67,10 @@ define void @test_store40(i40* %a, i40 %b) sanitize_hwaddress {
 ; ABORT: call void @__hwasan_storeN(i64 %[[A]], i64 5)
 ; RECOVER: call void @__hwasan_storeN_noabort(i64 %[[A]], i64 5)
 
-; CHECK: store i40 %b, i40* %a
+; CHECK: %[[A:[^ ]*]] = ptrtoint i40* %a to i64
+; CHECK: %[[UNTAGGED:[^ ]*]] = and i64 %[[A]], 72057594037927935
+; CHECK: %[[UNTAGGED_PTR:[^ ]*]] = inttoptr i64 %[[UNTAGGED]] to i40*
+; CHECK: store i40 %b, i40* %[[UNTAGGED_PTR]]
 ; CHECK: ret void
 
 entry: