diff --git a/clang/lib/Driver/SanitizerArgs.cpp b/clang/lib/Driver/SanitizerArgs.cpp
--- a/clang/lib/Driver/SanitizerArgs.cpp
+++ b/clang/lib/Driver/SanitizerArgs.cpp
@@ -1071,6 +1071,20 @@
   if (Sanitizers.has(SanitizerKind::HWAddress)) {
     CmdArgs.push_back("-target-feature");
     CmdArgs.push_back("+tagged-globals");
+
+    // Workaround for HWASan not implementing the +tagged-globals feature
+    // properly in GlobalISel, which is enabled by default at -O0 for aarch64.
+    // Once GlobalISel is disabled, -O0 uses FastISel, so we disable that as
+    // well to ensure we get SelectionDagISel where the feature is properly
+    // implemented.
+    // TODO(hctim): Implement proper ISel lowering for taking the address of
+    // tagged globals in at *least* GlobalISel. Probably okay to ignore FastISel
+    // as it's not part of any defaults set.
+    CmdArgs.push_back("-mllvm");
+    CmdArgs.push_back("--aarch64-enable-global-isel-at-O=-1"); // No GlobalISel.
+
+    CmdArgs.push_back("-mllvm");
+    CmdArgs.push_back("-fast-isel=false");
   }
 
   // MSan: Workaround for PR16386.
diff --git a/clang/test/Driver/fsanitize.c b/clang/test/Driver/fsanitize.c
--- a/clang/test/Driver/fsanitize.c
+++ b/clang/test/Driver/fsanitize.c
@@ -869,8 +869,12 @@
 // RUN: %clang -target x86_64-linux-gnu -fsanitize=hwaddress -fsanitize-hwaddress-abi=foo %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-HWASAN-FOO-ABI
 // CHECK-HWASAN-INTERCEPTOR-ABI: "-default-function-attr" "hwasan-abi=interceptor"
 // CHECK-HWASAN-INTERCEPTOR-ABI: "-target-feature" "+tagged-globals"
+// CHECK-HWASAN-INTERCEPTOR-ABI: "-mllvm" "--aarch64-enable-global-isel-at-O=-1"
+// CHECK-HWASAN-INTERCEPTOR-ABI: "-mllvm" "-fast-isel=false"
 // CHECK-HWASAN-PLATFORM-ABI: "-default-function-attr" "hwasan-abi=platform"
 // CHECK-HWASAN-PLATFORM-ABI: "-target-feature" "+tagged-globals"
+// CHECK-HWASAN-PLATFORM-ABI: "-mllvm" "--aarch64-enable-global-isel-at-O=-1"
+// CHECK-HWASAN-PLATFORM-ABI: "-mllvm" "-fast-isel=false"
 // CHECK-HWASAN-FOO-ABI: error: invalid value 'foo' in '-fsanitize-hwaddress-abi=foo'
 
 // RUN: %clang -target x86_64-linux-gnu -fsanitize=address,pointer-compare,pointer-subtract %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-POINTER-ALL
diff --git a/compiler-rt/test/hwasan/TestCases/exported-tagged-global.c b/compiler-rt/test/hwasan/TestCases/exported-tagged-global.c
new file mode 100644
--- /dev/null
+++ b/compiler-rt/test/hwasan/TestCases/exported-tagged-global.c
@@ -0,0 +1,16 @@
+// RUN: %clang_hwasan %s -o %t
+// RUN: %run %t
+// RUN: %clang_hwasan -O1 %s -o %t
+// RUN: %run %t
+
+static int global;
+
+__attribute__((optnone)) int* address_of_global() {
+  return &global;
+}
+
+int main(int argc, char **argv) {
+  int* global_address = address_of_global();
+  *global_address = 13;
+  return 0;
+}
diff --git a/llvm/test/CodeGen/AArch64/tagged-globals.ll b/llvm/test/CodeGen/AArch64/tagged-globals.ll
--- a/llvm/test/CodeGen/AArch64/tagged-globals.ll
+++ b/llvm/test/CodeGen/AArch64/tagged-globals.ll
@@ -1,31 +1,70 @@
-; RUN: llc < %s | FileCheck %s
+; RUN: llc --relocation-model=static < %s | FileCheck %s
+; RUN: llc --relocation-model=pic < %s | FileCheck %s -check-prefix=CHECK-PIC
 
 target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
 target triple = "aarch64-unknown-linux-android"
 
-@global = external hidden global i32
+@global = external global i32
 declare void @func()
 
 define i32* @global_addr() #0 {
   ; CHECK: global_addr:
-  ; CHECK: adrp x0, :pg_hi21_nc:global
-  ; CHECK: movk x0, #:prel_g3:global+4294967296
-  ; CHECK: add x0, x0, :lo12:global
+  ; CHECK: adrp [[REG:x[0-9]+]], :pg_hi21_nc:global
+  ; CHECK: movk [[REG]], #:prel_g3:global+4294967296
+  ; CHECK: add x0, [[REG]], :lo12:global
+  ; CHECK: ret
+
+  ; CHECK-PIC: global_addr:
+  ; CHECK-PIC: adrp [[REG:x[0-9]+]], :got:global
+  ; CHECK-PIC: ldr x0, {{\[}}[[REG]], :got_lo12:global]
+  ; CHECK-PIC: ret
+
   ret i32* @global
 }
 
 define i32 @global_load() #0 {
   ; CHECK: global_load:
-  ; CHECK: adrp x8, :pg_hi21_nc:global
-  ; CHECK: ldr w0, [x8, :lo12:global]
+  ; CHECK: adrp [[REG:x[0-9]+]], :pg_hi21_nc:global
+  ; CHECK: ldr w0, {{\[}}[[REG]], :lo12:global{{\]}}
+  ; CHECK: ret
+
+  ; CHECK-PIC: global_load:
+  ; CHECK-PIC: adrp [[REG:x[0-9]+]], :got:global
+  ; CHECK-PIC: ldr  [[REG]], {{\[}}[[REG]], :got_lo12:global]
+  ; CHECK-PIC: ldr w0, {{\[}}[[REG]]{{\]}}
+  ; CHECK-PIC: ret
+
   %load = load i32, i32* @global
   ret i32 %load
 }
 
+define void @global_store() #0 {
+  ; CHECK: global_store:
+  ; CHECK: adrp [[REG:x[0-9]+]], :pg_hi21_nc:global
+  ; CHECK: str wzr, {{\[}}[[REG]], :lo12:global{{\]}}
+  ; CHECK: ret
+
+  ; CHECK-PIC: global_store:
+  ; CHECK-PIC: adrp [[REG:x[0-9]+]], :got:global
+  ; CHECK-PIC: ldr  [[REG]], {{\[}}[[REG]], :got_lo12:global]
+  ; CHECK-PIC: str wzr, {{\[}}[[REG]]{{\]}}
+  ; CHECK-PIC: ret
+
+  store i32 0, i32* @global
+  ret void
+}
+
 define void ()* @func_addr() #0 {
   ; CHECK: func_addr:
-  ; CHECK: adrp x0, func
-  ; CHECK: add x0, x0, :lo12:func
+  ; CHECK: adrp [[REG:x[0-9]+]], func
+  ; CHECK: add x0, [[REG]], :lo12:func
+  ; CHECK: ret
+
+  ; CHECK-PIC: func_addr:
+  ; CHECK-PIC: adrp [[REG:x[0-9]+]], :got:func
+  ; CHECK-PIC: ldr  x0, {{\[}}[[REG]], :got_lo12:func]
+  ; CHECK-PIC: ret
+
   ret void ()* @func
 }