diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -16669,25 +16669,36 @@
 
   unsigned Size = AI->getType()->getPrimitiveSizeInBits();
   if (Size > 128) return AtomicExpansionKind::None;
-  // Nand not supported in LSE.
-  if (AI->getOperation() == AtomicRMWInst::Nand) return AtomicExpansionKind::LLSC;
-  // Leave 128 bits to LLSC.
-  if (Subtarget->hasLSE() && Size < 128)
-    return AtomicExpansionKind::None;
-  if (Subtarget->outlineAtomics() && Size < 128) {
-    // [U]Min/[U]Max RWM atomics are used in __sync_fetch_ libcalls so far.
-    // Don't outline them unless
-    // (1) high level <atomic> support approved:
-    //   http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2020/p0493r1.pdf
-    // (2) low level libgcc and compiler-rt support implemented by:
-    //   min/max outline atomics helpers
-    if (AI->getOperation() != AtomicRMWInst::Min &&
-        AI->getOperation() != AtomicRMWInst::Max &&
-        AI->getOperation() != AtomicRMWInst::UMin &&
-        AI->getOperation() != AtomicRMWInst::UMax) {
+
+  // Nand is not supported in LSE.
+  // Leave 128 bits to LLSC or CmpXChg.
+  if (AI->getOperation() != AtomicRMWInst::Nand && Size < 128) {
+    if (Subtarget->hasLSE())
       return AtomicExpansionKind::None;
+    if (Subtarget->outlineAtomics()) {
+      // [U]Min/[U]Max RWM atomics are used in __sync_fetch_ libcalls so far.
+      // Don't outline them unless
+      // (1) high level <atomic> support approved:
+      //   http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2020/p0493r1.pdf
+      // (2) low level libgcc and compiler-rt support implemented by:
+      //   min/max outline atomics helpers
+      if (AI->getOperation() != AtomicRMWInst::Min &&
+          AI->getOperation() != AtomicRMWInst::Max &&
+          AI->getOperation() != AtomicRMWInst::UMin &&
+          AI->getOperation() != AtomicRMWInst::UMax) {
+        return AtomicExpansionKind::None;
+      }
     }
   }
+
+  // At -O0, fast-regalloc cannot cope with the live vregs necessary to
+  // implement atomicrmw without spilling. If the target address is also on the
+  // stack and close enough to the spill slot, this can lead to a situation
+  // where the monitor always gets cleared and the atomic operation can never
+  // succeed. So at -O0 lower this operation to a CAS loop.
+  if (getTargetMachine().getOptLevel() == CodeGenOpt::None)
+    return AtomicExpansionKind::CmpXChg;
+
   return AtomicExpansionKind::LLSC;
 }
 
diff --git a/llvm/test/CodeGen/AArch64/GlobalISel/arm64-atomic.ll b/llvm/test/CodeGen/AArch64/GlobalISel/arm64-atomic.ll
--- a/llvm/test/CodeGen/AArch64/GlobalISel/arm64-atomic.ll
+++ b/llvm/test/CodeGen/AArch64/GlobalISel/arm64-atomic.ll
@@ -225,22 +225,37 @@
 ;
 ; CHECK-NOLSE-O0-LABEL: fetch_and_nand:
 ; CHECK-NOLSE-O0:       ; %bb.0:
-; CHECK-NOLSE-O0-NEXT:    sub sp, sp, #16 ; =16
-; CHECK-NOLSE-O0-NEXT:    str x0, [sp, #8] ; 8-byte Folded Spill
+; CHECK-NOLSE-O0-NEXT:    sub sp, sp, #32 ; =32
+; CHECK-NOLSE-O0-NEXT:    str x0, [sp, #16] ; 8-byte Folded Spill
+; CHECK-NOLSE-O0-NEXT:    ldr w8, [x0]
+; CHECK-NOLSE-O0-NEXT:    str w8, [sp, #28] ; 4-byte Folded Spill
 ; CHECK-NOLSE-O0-NEXT:  LBB4_1: ; %atomicrmw.start
-; CHECK-NOLSE-O0-NEXT:    ; =>This Inner Loop Header: Depth=1
-; CHECK-NOLSE-O0-NEXT:    ldr x10, [sp, #8] ; 8-byte Folded Reload
-; CHECK-NOLSE-O0-NEXT:    ldxr w8, [x10]
-; CHECK-NOLSE-O0-NEXT:    ; kill: def $x8 killed $w8
-; CHECK-NOLSE-O0-NEXT:    ; kill: def $w8 killed $w8 killed $x8
-; CHECK-NOLSE-O0-NEXT:    str w8, [sp, #4] ; 4-byte Folded Spill
-; CHECK-NOLSE-O0-NEXT:    and w8, w8, #0x7
-; CHECK-NOLSE-O0-NEXT:    mvn w9, w8
-; CHECK-NOLSE-O0-NEXT:    stlxr w8, w9, [x10]
-; CHECK-NOLSE-O0-NEXT:    cbnz w8, LBB4_1
-; CHECK-NOLSE-O0-NEXT:  ; %bb.2: ; %atomicrmw.end
-; CHECK-NOLSE-O0-NEXT:    ldr w0, [sp, #4] ; 4-byte Folded Reload
-; CHECK-NOLSE-O0-NEXT:    add sp, sp, #16 ; =16
+; CHECK-NOLSE-O0-NEXT:    ; =>This Loop Header: Depth=1
+; CHECK-NOLSE-O0-NEXT:    ; Child Loop BB4_2 Depth 2
+; CHECK-NOLSE-O0-NEXT:    ldr w8, [sp, #28] ; 4-byte Folded Reload
+; CHECK-NOLSE-O0-NEXT:    ldr x11, [sp, #16] ; 8-byte Folded Reload
+; CHECK-NOLSE-O0-NEXT:    and w9, w8, #0x7
+; CHECK-NOLSE-O0-NEXT:    mvn w12, w9
+; CHECK-NOLSE-O0-NEXT:  LBB4_2: ; %atomicrmw.start
+; CHECK-NOLSE-O0-NEXT:    ; Parent Loop BB4_1 Depth=1
+; CHECK-NOLSE-O0-NEXT:    ; => This Inner Loop Header: Depth=2
+; CHECK-NOLSE-O0-NEXT:    ldaxr w9, [x11]
+; CHECK-NOLSE-O0-NEXT:    cmp w9, w8
+; CHECK-NOLSE-O0-NEXT:    b.ne LBB4_4
+; CHECK-NOLSE-O0-NEXT:  ; %bb.3: ; %atomicrmw.start
+; CHECK-NOLSE-O0-NEXT:    ; in Loop: Header=BB4_2 Depth=2
+; CHECK-NOLSE-O0-NEXT:    stlxr w10, w12, [x11]
+; CHECK-NOLSE-O0-NEXT:    cbnz w10, LBB4_2
+; CHECK-NOLSE-O0-NEXT:  LBB4_4: ; %atomicrmw.start
+; CHECK-NOLSE-O0-NEXT:    ; in Loop: Header=BB4_1 Depth=1
+; CHECK-NOLSE-O0-NEXT:    str w9, [sp, #12] ; 4-byte Folded Spill
+; CHECK-NOLSE-O0-NEXT:    subs w8, w9, w8
+; CHECK-NOLSE-O0-NEXT:    cset w8, eq
+; CHECK-NOLSE-O0-NEXT:    str w9, [sp, #28] ; 4-byte Folded Spill
+; CHECK-NOLSE-O0-NEXT:    tbz w8, #0, LBB4_1
+; CHECK-NOLSE-O0-NEXT:  ; %bb.5: ; %atomicrmw.end
+; CHECK-NOLSE-O0-NEXT:    ldr w0, [sp, #12] ; 4-byte Folded Reload
+; CHECK-NOLSE-O0-NEXT:    add sp, sp, #32 ; =32
 ; CHECK-NOLSE-O0-NEXT:    ret
 ;
 ; CHECK-LSE-O1-LABEL: fetch_and_nand:
@@ -258,22 +273,26 @@
 ;
 ; CHECK-LSE-O0-LABEL: fetch_and_nand:
 ; CHECK-LSE-O0:       ; %bb.0:
-; CHECK-LSE-O0-NEXT:    sub sp, sp, #16 ; =16
-; CHECK-LSE-O0-NEXT:    str x0, [sp, #8] ; 8-byte Folded Spill
+; CHECK-LSE-O0-NEXT:    sub sp, sp, #32 ; =32
+; CHECK-LSE-O0-NEXT:    str x0, [sp, #16] ; 8-byte Folded Spill
+; CHECK-LSE-O0-NEXT:    ldr w8, [x0]
+; CHECK-LSE-O0-NEXT:    str w8, [sp, #28] ; 4-byte Folded Spill
 ; CHECK-LSE-O0-NEXT:  LBB4_1: ; %atomicrmw.start
 ; CHECK-LSE-O0-NEXT:    ; =>This Inner Loop Header: Depth=1
-; CHECK-LSE-O0-NEXT:    ldr x10, [sp, #8] ; 8-byte Folded Reload
-; CHECK-LSE-O0-NEXT:    ldxr w8, [x10]
-; CHECK-LSE-O0-NEXT:    ; kill: def $x8 killed $w8
-; CHECK-LSE-O0-NEXT:    ; kill: def $w8 killed $w8 killed $x8
-; CHECK-LSE-O0-NEXT:    str w8, [sp, #4] ; 4-byte Folded Spill
-; CHECK-LSE-O0-NEXT:    and w8, w8, #0x7
-; CHECK-LSE-O0-NEXT:    mvn w9, w8
-; CHECK-LSE-O0-NEXT:    stlxr w8, w9, [x10]
-; CHECK-LSE-O0-NEXT:    cbnz w8, LBB4_1
+; CHECK-LSE-O0-NEXT:    ldr w8, [sp, #28] ; 4-byte Folded Reload
+; CHECK-LSE-O0-NEXT:    ldr x11, [sp, #16] ; 8-byte Folded Reload
+; CHECK-LSE-O0-NEXT:    and w9, w8, #0x7
+; CHECK-LSE-O0-NEXT:    mvn w10, w9
+; CHECK-LSE-O0-NEXT:    mov x9, x8
+; CHECK-LSE-O0-NEXT:    casl w9, w10, [x11]
+; CHECK-LSE-O0-NEXT:    str w9, [sp, #12] ; 4-byte Folded Spill
+; CHECK-LSE-O0-NEXT:    subs w8, w9, w8
+; CHECK-LSE-O0-NEXT:    cset w8, eq
+; CHECK-LSE-O0-NEXT:    str w9, [sp, #28] ; 4-byte Folded Spill
+; CHECK-LSE-O0-NEXT:    tbz w8, #0, LBB4_1
 ; CHECK-LSE-O0-NEXT:  ; %bb.2: ; %atomicrmw.end
-; CHECK-LSE-O0-NEXT:    ldr w0, [sp, #4] ; 4-byte Folded Reload
-; CHECK-LSE-O0-NEXT:    add sp, sp, #16 ; =16
+; CHECK-LSE-O0-NEXT:    ldr w0, [sp, #12] ; 4-byte Folded Reload
+; CHECK-LSE-O0-NEXT:    add sp, sp, #32 ; =32
 ; CHECK-LSE-O0-NEXT:    ret
   %val = atomicrmw nand i32* %p, i32 7 release
   ret i32 %val
@@ -295,20 +314,37 @@
 ;
 ; CHECK-NOLSE-O0-LABEL: fetch_and_nand_64:
 ; CHECK-NOLSE-O0:       ; %bb.0:
-; CHECK-NOLSE-O0-NEXT:    sub sp, sp, #16 ; =16
-; CHECK-NOLSE-O0-NEXT:    str x0, [sp, #8] ; 8-byte Folded Spill
+; CHECK-NOLSE-O0-NEXT:    sub sp, sp, #32 ; =32
+; CHECK-NOLSE-O0-NEXT:    str x0, [sp, #16] ; 8-byte Folded Spill
+; CHECK-NOLSE-O0-NEXT:    ldr x8, [x0]
+; CHECK-NOLSE-O0-NEXT:    str x8, [sp, #24] ; 8-byte Folded Spill
 ; CHECK-NOLSE-O0-NEXT:  LBB5_1: ; %atomicrmw.start
-; CHECK-NOLSE-O0-NEXT:    ; =>This Inner Loop Header: Depth=1
-; CHECK-NOLSE-O0-NEXT:    ldr x10, [sp, #8] ; 8-byte Folded Reload
-; CHECK-NOLSE-O0-NEXT:    ldaxr x8, [x10]
-; CHECK-NOLSE-O0-NEXT:    str x8, [sp] ; 8-byte Folded Spill
-; CHECK-NOLSE-O0-NEXT:    and x8, x8, #0x7
-; CHECK-NOLSE-O0-NEXT:    mvn x9, x8
-; CHECK-NOLSE-O0-NEXT:    stlxr w8, x9, [x10]
-; CHECK-NOLSE-O0-NEXT:    cbnz w8, LBB5_1
-; CHECK-NOLSE-O0-NEXT:  ; %bb.2: ; %atomicrmw.end
-; CHECK-NOLSE-O0-NEXT:    ldr x0, [sp] ; 8-byte Folded Reload
-; CHECK-NOLSE-O0-NEXT:    add sp, sp, #16 ; =16
+; CHECK-NOLSE-O0-NEXT:    ; =>This Loop Header: Depth=1
+; CHECK-NOLSE-O0-NEXT:    ; Child Loop BB5_2 Depth 2
+; CHECK-NOLSE-O0-NEXT:    ldr x8, [sp, #24] ; 8-byte Folded Reload
+; CHECK-NOLSE-O0-NEXT:    ldr x11, [sp, #16] ; 8-byte Folded Reload
+; CHECK-NOLSE-O0-NEXT:    and x9, x8, #0x7
+; CHECK-NOLSE-O0-NEXT:    mvn x12, x9
+; CHECK-NOLSE-O0-NEXT:  LBB5_2: ; %atomicrmw.start
+; CHECK-NOLSE-O0-NEXT:    ; Parent Loop BB5_1 Depth=1
+; CHECK-NOLSE-O0-NEXT:    ; => This Inner Loop Header: Depth=2
+; CHECK-NOLSE-O0-NEXT:    ldaxr x9, [x11]
+; CHECK-NOLSE-O0-NEXT:    cmp x9, x8
+; CHECK-NOLSE-O0-NEXT:    b.ne LBB5_4
+; CHECK-NOLSE-O0-NEXT:  ; %bb.3: ; %atomicrmw.start
+; CHECK-NOLSE-O0-NEXT:    ; in Loop: Header=BB5_2 Depth=2
+; CHECK-NOLSE-O0-NEXT:    stlxr w10, x12, [x11]
+; CHECK-NOLSE-O0-NEXT:    cbnz w10, LBB5_2
+; CHECK-NOLSE-O0-NEXT:  LBB5_4: ; %atomicrmw.start
+; CHECK-NOLSE-O0-NEXT:    ; in Loop: Header=BB5_1 Depth=1
+; CHECK-NOLSE-O0-NEXT:    str x9, [sp, #8] ; 8-byte Folded Spill
+; CHECK-NOLSE-O0-NEXT:    subs x8, x9, x8
+; CHECK-NOLSE-O0-NEXT:    cset w8, eq
+; CHECK-NOLSE-O0-NEXT:    str x9, [sp, #24] ; 8-byte Folded Spill
+; CHECK-NOLSE-O0-NEXT:    tbz w8, #0, LBB5_1
+; CHECK-NOLSE-O0-NEXT:  ; %bb.5: ; %atomicrmw.end
+; CHECK-NOLSE-O0-NEXT:    ldr x0, [sp, #8] ; 8-byte Folded Reload
+; CHECK-NOLSE-O0-NEXT:    add sp, sp, #32 ; =32
 ; CHECK-NOLSE-O0-NEXT:    ret
 ;
 ; CHECK-LSE-O1-LABEL: fetch_and_nand_64:
@@ -326,20 +362,26 @@
 ;
 ; CHECK-LSE-O0-LABEL: fetch_and_nand_64:
 ; CHECK-LSE-O0:       ; %bb.0:
-; CHECK-LSE-O0-NEXT:    sub sp, sp, #16 ; =16
-; CHECK-LSE-O0-NEXT:    str x0, [sp, #8] ; 8-byte Folded Spill
+; CHECK-LSE-O0-NEXT:    sub sp, sp, #32 ; =32
+; CHECK-LSE-O0-NEXT:    str x0, [sp, #16] ; 8-byte Folded Spill
+; CHECK-LSE-O0-NEXT:    ldr x8, [x0]
+; CHECK-LSE-O0-NEXT:    str x8, [sp, #24] ; 8-byte Folded Spill
 ; CHECK-LSE-O0-NEXT:  LBB5_1: ; %atomicrmw.start
 ; CHECK-LSE-O0-NEXT:    ; =>This Inner Loop Header: Depth=1
-; CHECK-LSE-O0-NEXT:    ldr x10, [sp, #8] ; 8-byte Folded Reload
-; CHECK-LSE-O0-NEXT:    ldaxr x8, [x10]
-; CHECK-LSE-O0-NEXT:    str x8, [sp] ; 8-byte Folded Spill
-; CHECK-LSE-O0-NEXT:    and x8, x8, #0x7
-; CHECK-LSE-O0-NEXT:    mvn x9, x8
-; CHECK-LSE-O0-NEXT:    stlxr w8, x9, [x10]
-; CHECK-LSE-O0-NEXT:    cbnz w8, LBB5_1
+; CHECK-LSE-O0-NEXT:    ldr x8, [sp, #24] ; 8-byte Folded Reload
+; CHECK-LSE-O0-NEXT:    ldr x11, [sp, #16] ; 8-byte Folded Reload
+; CHECK-LSE-O0-NEXT:    and x9, x8, #0x7
+; CHECK-LSE-O0-NEXT:    mvn x10, x9
+; CHECK-LSE-O0-NEXT:    mov x9, x8
+; CHECK-LSE-O0-NEXT:    casal x9, x10, [x11]
+; CHECK-LSE-O0-NEXT:    str x9, [sp, #8] ; 8-byte Folded Spill
+; CHECK-LSE-O0-NEXT:    subs x8, x9, x8
+; CHECK-LSE-O0-NEXT:    cset w8, eq
+; CHECK-LSE-O0-NEXT:    str x9, [sp, #24] ; 8-byte Folded Spill
+; CHECK-LSE-O0-NEXT:    tbz w8, #0, LBB5_1
 ; CHECK-LSE-O0-NEXT:  ; %bb.2: ; %atomicrmw.end
-; CHECK-LSE-O0-NEXT:    ldr x0, [sp] ; 8-byte Folded Reload
-; CHECK-LSE-O0-NEXT:    add sp, sp, #16 ; =16
+; CHECK-LSE-O0-NEXT:    ldr x0, [sp, #8] ; 8-byte Folded Reload
+; CHECK-LSE-O0-NEXT:    add sp, sp, #32 ; =32
 ; CHECK-LSE-O0-NEXT:    ret
   %val = atomicrmw nand i64* %p, i64 7 acq_rel
   ret i64 %val
@@ -361,22 +403,37 @@
 ;
 ; CHECK-NOLSE-O0-LABEL: fetch_and_or:
 ; CHECK-NOLSE-O0:       ; %bb.0:
-; CHECK-NOLSE-O0-NEXT:    sub sp, sp, #16 ; =16
-; CHECK-NOLSE-O0-NEXT:    str x0, [sp, #8] ; 8-byte Folded Spill
+; CHECK-NOLSE-O0-NEXT:    sub sp, sp, #32 ; =32
+; CHECK-NOLSE-O0-NEXT:    str x0, [sp, #16] ; 8-byte Folded Spill
+; CHECK-NOLSE-O0-NEXT:    ldr w8, [x0]
+; CHECK-NOLSE-O0-NEXT:    str w8, [sp, #28] ; 4-byte Folded Spill
 ; CHECK-NOLSE-O0-NEXT:  LBB6_1: ; %atomicrmw.start
-; CHECK-NOLSE-O0-NEXT:    ; =>This Inner Loop Header: Depth=1
-; CHECK-NOLSE-O0-NEXT:    ldr x10, [sp, #8] ; 8-byte Folded Reload
-; CHECK-NOLSE-O0-NEXT:    ldaxr w8, [x10]
-; CHECK-NOLSE-O0-NEXT:    ; kill: def $x8 killed $w8
-; CHECK-NOLSE-O0-NEXT:    ; kill: def $w8 killed $w8 killed $x8
-; CHECK-NOLSE-O0-NEXT:    str w8, [sp, #4] ; 4-byte Folded Spill
+; CHECK-NOLSE-O0-NEXT:    ; =>This Loop Header: Depth=1
+; CHECK-NOLSE-O0-NEXT:    ; Child Loop BB6_2 Depth 2
+; CHECK-NOLSE-O0-NEXT:    ldr w8, [sp, #28] ; 4-byte Folded Reload
+; CHECK-NOLSE-O0-NEXT:    ldr x11, [sp, #16] ; 8-byte Folded Reload
 ; CHECK-NOLSE-O0-NEXT:    mov w9, #5
-; CHECK-NOLSE-O0-NEXT:    orr w9, w8, w9
-; CHECK-NOLSE-O0-NEXT:    stlxr w8, w9, [x10]
-; CHECK-NOLSE-O0-NEXT:    cbnz w8, LBB6_1
-; CHECK-NOLSE-O0-NEXT:  ; %bb.2: ; %atomicrmw.end
-; CHECK-NOLSE-O0-NEXT:    ldr w0, [sp, #4] ; 4-byte Folded Reload
-; CHECK-NOLSE-O0-NEXT:    add sp, sp, #16 ; =16
+; CHECK-NOLSE-O0-NEXT:    orr w12, w8, w9
+; CHECK-NOLSE-O0-NEXT:  LBB6_2: ; %atomicrmw.start
+; CHECK-NOLSE-O0-NEXT:    ; Parent Loop BB6_1 Depth=1
+; CHECK-NOLSE-O0-NEXT:    ; => This Inner Loop Header: Depth=2
+; CHECK-NOLSE-O0-NEXT:    ldaxr w9, [x11]
+; CHECK-NOLSE-O0-NEXT:    cmp w9, w8
+; CHECK-NOLSE-O0-NEXT:    b.ne LBB6_4
+; CHECK-NOLSE-O0-NEXT:  ; %bb.3: ; %atomicrmw.start
+; CHECK-NOLSE-O0-NEXT:    ; in Loop: Header=BB6_2 Depth=2
+; CHECK-NOLSE-O0-NEXT:    stlxr w10, w12, [x11]
+; CHECK-NOLSE-O0-NEXT:    cbnz w10, LBB6_2
+; CHECK-NOLSE-O0-NEXT:  LBB6_4: ; %atomicrmw.start
+; CHECK-NOLSE-O0-NEXT:    ; in Loop: Header=BB6_1 Depth=1
+; CHECK-NOLSE-O0-NEXT:    str w9, [sp, #12] ; 4-byte Folded Spill
+; CHECK-NOLSE-O0-NEXT:    subs w8, w9, w8
+; CHECK-NOLSE-O0-NEXT:    cset w8, eq
+; CHECK-NOLSE-O0-NEXT:    str w9, [sp, #28] ; 4-byte Folded Spill
+; CHECK-NOLSE-O0-NEXT:    tbz w8, #0, LBB6_1
+; CHECK-NOLSE-O0-NEXT:  ; %bb.5: ; %atomicrmw.end
+; CHECK-NOLSE-O0-NEXT:    ldr w0, [sp, #12] ; 4-byte Folded Reload
+; CHECK-NOLSE-O0-NEXT:    add sp, sp, #32 ; =32
 ; CHECK-NOLSE-O0-NEXT:    ret
 ;
 ; CHECK-LSE-O1-LABEL: fetch_and_or:
@@ -409,19 +466,36 @@
 ;
 ; CHECK-NOLSE-O0-LABEL: fetch_and_or_64:
 ; CHECK-NOLSE-O0:       ; %bb.0:
-; CHECK-NOLSE-O0-NEXT:    sub sp, sp, #16 ; =16
-; CHECK-NOLSE-O0-NEXT:    str x0, [sp, #8] ; 8-byte Folded Spill
+; CHECK-NOLSE-O0-NEXT:    sub sp, sp, #32 ; =32
+; CHECK-NOLSE-O0-NEXT:    str x0, [sp, #16] ; 8-byte Folded Spill
+; CHECK-NOLSE-O0-NEXT:    ldr x8, [x0]
+; CHECK-NOLSE-O0-NEXT:    str x8, [sp, #24] ; 8-byte Folded Spill
 ; CHECK-NOLSE-O0-NEXT:  LBB7_1: ; %atomicrmw.start
-; CHECK-NOLSE-O0-NEXT:    ; =>This Inner Loop Header: Depth=1
-; CHECK-NOLSE-O0-NEXT:    ldr x10, [sp, #8] ; 8-byte Folded Reload
-; CHECK-NOLSE-O0-NEXT:    ldxr x8, [x10]
-; CHECK-NOLSE-O0-NEXT:    str x8, [sp] ; 8-byte Folded Spill
-; CHECK-NOLSE-O0-NEXT:    orr x9, x8, #0x7
-; CHECK-NOLSE-O0-NEXT:    stxr w8, x9, [x10]
-; CHECK-NOLSE-O0-NEXT:    cbnz w8, LBB7_1
-; CHECK-NOLSE-O0-NEXT:  ; %bb.2: ; %atomicrmw.end
-; CHECK-NOLSE-O0-NEXT:    ldr x0, [sp] ; 8-byte Folded Reload
-; CHECK-NOLSE-O0-NEXT:    add sp, sp, #16 ; =16
+; CHECK-NOLSE-O0-NEXT:    ; =>This Loop Header: Depth=1
+; CHECK-NOLSE-O0-NEXT:    ; Child Loop BB7_2 Depth 2
+; CHECK-NOLSE-O0-NEXT:    ldr x8, [sp, #24] ; 8-byte Folded Reload
+; CHECK-NOLSE-O0-NEXT:    ldr x11, [sp, #16] ; 8-byte Folded Reload
+; CHECK-NOLSE-O0-NEXT:    orr x12, x8, #0x7
+; CHECK-NOLSE-O0-NEXT:  LBB7_2: ; %atomicrmw.start
+; CHECK-NOLSE-O0-NEXT:    ; Parent Loop BB7_1 Depth=1
+; CHECK-NOLSE-O0-NEXT:    ; => This Inner Loop Header: Depth=2
+; CHECK-NOLSE-O0-NEXT:    ldaxr x9, [x11]
+; CHECK-NOLSE-O0-NEXT:    cmp x9, x8
+; CHECK-NOLSE-O0-NEXT:    b.ne LBB7_4
+; CHECK-NOLSE-O0-NEXT:  ; %bb.3: ; %atomicrmw.start
+; CHECK-NOLSE-O0-NEXT:    ; in Loop: Header=BB7_2 Depth=2
+; CHECK-NOLSE-O0-NEXT:    stlxr w10, x12, [x11]
+; CHECK-NOLSE-O0-NEXT:    cbnz w10, LBB7_2
+; CHECK-NOLSE-O0-NEXT:  LBB7_4: ; %atomicrmw.start
+; CHECK-NOLSE-O0-NEXT:    ; in Loop: Header=BB7_1 Depth=1
+; CHECK-NOLSE-O0-NEXT:    str x9, [sp, #8] ; 8-byte Folded Spill
+; CHECK-NOLSE-O0-NEXT:    subs x8, x9, x8
+; CHECK-NOLSE-O0-NEXT:    cset w8, eq
+; CHECK-NOLSE-O0-NEXT:    str x9, [sp, #24] ; 8-byte Folded Spill
+; CHECK-NOLSE-O0-NEXT:    tbz w8, #0, LBB7_1
+; CHECK-NOLSE-O0-NEXT:  ; %bb.5: ; %atomicrmw.end
+; CHECK-NOLSE-O0-NEXT:    ldr x0, [sp, #8] ; 8-byte Folded Reload
+; CHECK-NOLSE-O0-NEXT:    add sp, sp, #32 ; =32
 ; CHECK-NOLSE-O0-NEXT:    ret
 ;
 ; CHECK-LSE-O1-LABEL: fetch_and_or_64:
diff --git a/llvm/test/CodeGen/AArch64/atomicrmw-O0.ll b/llvm/test/CodeGen/AArch64/atomicrmw-O0.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/CodeGen/AArch64/atomicrmw-O0.ll
@@ -0,0 +1,697 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -verify-machineinstrs -mtriple=aarch64-- -O0 -fast-isel=0 -global-isel=false %s -o - | FileCheck %s -check-prefix=NOLSE
+; RUN: llc -verify-machineinstrs -mtriple=aarch64-- -mattr=+lse -O0 -fast-isel=0 -global-isel=false %s -o - | FileCheck %s -check-prefix=LSE
+
+; Ensure there's no stack spill in between ldxr/stxr pairs.
+
+define i8 @test_rmw_add_8(i8* %dst)   {
+; NOLSE-LABEL: test_rmw_add_8:
+; NOLSE:       // %bb.0: // %entry
+; NOLSE-NEXT:    sub sp, sp, #32 // =32
+; NOLSE-NEXT:    .cfi_def_cfa_offset 32
+; NOLSE-NEXT:    str x0, [sp, #16] // 8-byte Folded Spill
+; NOLSE-NEXT:    ldrb w8, [x0]
+; NOLSE-NEXT:    str w8, [sp, #28] // 4-byte Folded Spill
+; NOLSE-NEXT:    b .LBB0_1
+; NOLSE-NEXT:  .LBB0_1: // %atomicrmw.start
+; NOLSE-NEXT:    // =>This Loop Header: Depth=1
+; NOLSE-NEXT:    // Child Loop BB0_2 Depth 2
+; NOLSE-NEXT:    ldr w9, [sp, #28] // 4-byte Folded Reload
+; NOLSE-NEXT:    ldr x11, [sp, #16] // 8-byte Folded Reload
+; NOLSE-NEXT:    add w12, w9, #1 // =1
+; NOLSE-NEXT:  .LBB0_2: // %atomicrmw.start
+; NOLSE-NEXT:    // Parent Loop BB0_1 Depth=1
+; NOLSE-NEXT:    // => This Inner Loop Header: Depth=2
+; NOLSE-NEXT:    ldaxrb w8, [x11]
+; NOLSE-NEXT:    cmp w8, w9, uxtb
+; NOLSE-NEXT:    b.ne .LBB0_4
+; NOLSE-NEXT:  // %bb.3: // %atomicrmw.start
+; NOLSE-NEXT:    // in Loop: Header=BB0_2 Depth=2
+; NOLSE-NEXT:    stlxrb w10, w12, [x11]
+; NOLSE-NEXT:    cbnz w10, .LBB0_2
+; NOLSE-NEXT:  .LBB0_4: // %atomicrmw.start
+; NOLSE-NEXT:    // in Loop: Header=BB0_1 Depth=1
+; NOLSE-NEXT:    subs w9, w8, w9, uxtb
+; NOLSE-NEXT:    cset w9, eq
+; NOLSE-NEXT:    str w8, [sp, #12] // 4-byte Folded Spill
+; NOLSE-NEXT:    subs w9, w9, #1 // =1
+; NOLSE-NEXT:    str w8, [sp, #28] // 4-byte Folded Spill
+; NOLSE-NEXT:    b.ne .LBB0_1
+; NOLSE-NEXT:    b .LBB0_5
+; NOLSE-NEXT:  .LBB0_5: // %atomicrmw.end
+; NOLSE-NEXT:    ldr w0, [sp, #12] // 4-byte Folded Reload
+; NOLSE-NEXT:    add sp, sp, #32 // =32
+; NOLSE-NEXT:    ret
+;
+; LSE-LABEL: test_rmw_add_8:
+; LSE:       // %bb.0: // %entry
+; LSE-NEXT:    mov w8, #1
+; LSE-NEXT:    ldaddalb w8, w0, [x0]
+; LSE-NEXT:    ret
+entry:
+  %res = atomicrmw add i8* %dst, i8 1 seq_cst
+  ret i8 %res
+}
+
+define i16 @test_rmw_add_16(i16* %dst)   {
+; NOLSE-LABEL: test_rmw_add_16:
+; NOLSE:       // %bb.0: // %entry
+; NOLSE-NEXT:    sub sp, sp, #32 // =32
+; NOLSE-NEXT:    .cfi_def_cfa_offset 32
+; NOLSE-NEXT:    str x0, [sp, #16] // 8-byte Folded Spill
+; NOLSE-NEXT:    ldrh w8, [x0]
+; NOLSE-NEXT:    str w8, [sp, #28] // 4-byte Folded Spill
+; NOLSE-NEXT:    b .LBB1_1
+; NOLSE-NEXT:  .LBB1_1: // %atomicrmw.start
+; NOLSE-NEXT:    // =>This Loop Header: Depth=1
+; NOLSE-NEXT:    // Child Loop BB1_2 Depth 2
+; NOLSE-NEXT:    ldr w9, [sp, #28] // 4-byte Folded Reload
+; NOLSE-NEXT:    ldr x11, [sp, #16] // 8-byte Folded Reload
+; NOLSE-NEXT:    add w12, w9, #1 // =1
+; NOLSE-NEXT:  .LBB1_2: // %atomicrmw.start
+; NOLSE-NEXT:    // Parent Loop BB1_1 Depth=1
+; NOLSE-NEXT:    // => This Inner Loop Header: Depth=2
+; NOLSE-NEXT:    ldaxrh w8, [x11]
+; NOLSE-NEXT:    cmp w8, w9, uxth
+; NOLSE-NEXT:    b.ne .LBB1_4
+; NOLSE-NEXT:  // %bb.3: // %atomicrmw.start
+; NOLSE-NEXT:    // in Loop: Header=BB1_2 Depth=2
+; NOLSE-NEXT:    stlxrh w10, w12, [x11]
+; NOLSE-NEXT:    cbnz w10, .LBB1_2
+; NOLSE-NEXT:  .LBB1_4: // %atomicrmw.start
+; NOLSE-NEXT:    // in Loop: Header=BB1_1 Depth=1
+; NOLSE-NEXT:    subs w9, w8, w9, uxth
+; NOLSE-NEXT:    cset w9, eq
+; NOLSE-NEXT:    str w8, [sp, #12] // 4-byte Folded Spill
+; NOLSE-NEXT:    subs w9, w9, #1 // =1
+; NOLSE-NEXT:    str w8, [sp, #28] // 4-byte Folded Spill
+; NOLSE-NEXT:    b.ne .LBB1_1
+; NOLSE-NEXT:    b .LBB1_5
+; NOLSE-NEXT:  .LBB1_5: // %atomicrmw.end
+; NOLSE-NEXT:    ldr w0, [sp, #12] // 4-byte Folded Reload
+; NOLSE-NEXT:    add sp, sp, #32 // =32
+; NOLSE-NEXT:    ret
+;
+; LSE-LABEL: test_rmw_add_16:
+; LSE:       // %bb.0: // %entry
+; LSE-NEXT:    mov w8, #1
+; LSE-NEXT:    ldaddalh w8, w0, [x0]
+; LSE-NEXT:    ret
+entry:
+  %res = atomicrmw add i16* %dst, i16 1 seq_cst
+  ret i16 %res
+}
+
+define i32 @test_rmw_add_32(i32* %dst)   {
+; NOLSE-LABEL: test_rmw_add_32:
+; NOLSE:       // %bb.0: // %entry
+; NOLSE-NEXT:    sub sp, sp, #32 // =32
+; NOLSE-NEXT:    .cfi_def_cfa_offset 32
+; NOLSE-NEXT:    str x0, [sp, #16] // 8-byte Folded Spill
+; NOLSE-NEXT:    ldr w8, [x0]
+; NOLSE-NEXT:    str w8, [sp, #28] // 4-byte Folded Spill
+; NOLSE-NEXT:    b .LBB2_1
+; NOLSE-NEXT:  .LBB2_1: // %atomicrmw.start
+; NOLSE-NEXT:    // =>This Loop Header: Depth=1
+; NOLSE-NEXT:    // Child Loop BB2_2 Depth 2
+; NOLSE-NEXT:    ldr w9, [sp, #28] // 4-byte Folded Reload
+; NOLSE-NEXT:    ldr x11, [sp, #16] // 8-byte Folded Reload
+; NOLSE-NEXT:    add w12, w9, #1 // =1
+; NOLSE-NEXT:  .LBB2_2: // %atomicrmw.start
+; NOLSE-NEXT:    // Parent Loop BB2_1 Depth=1
+; NOLSE-NEXT:    // => This Inner Loop Header: Depth=2
+; NOLSE-NEXT:    ldaxr w8, [x11]
+; NOLSE-NEXT:    cmp w8, w9
+; NOLSE-NEXT:    b.ne .LBB2_4
+; NOLSE-NEXT:  // %bb.3: // %atomicrmw.start
+; NOLSE-NEXT:    // in Loop: Header=BB2_2 Depth=2
+; NOLSE-NEXT:    stlxr w10, w12, [x11]
+; NOLSE-NEXT:    cbnz w10, .LBB2_2
+; NOLSE-NEXT:  .LBB2_4: // %atomicrmw.start
+; NOLSE-NEXT:    // in Loop: Header=BB2_1 Depth=1
+; NOLSE-NEXT:    subs w9, w8, w9
+; NOLSE-NEXT:    cset w9, eq
+; NOLSE-NEXT:    str w8, [sp, #12] // 4-byte Folded Spill
+; NOLSE-NEXT:    subs w9, w9, #1 // =1
+; NOLSE-NEXT:    str w8, [sp, #28] // 4-byte Folded Spill
+; NOLSE-NEXT:    b.ne .LBB2_1
+; NOLSE-NEXT:    b .LBB2_5
+; NOLSE-NEXT:  .LBB2_5: // %atomicrmw.end
+; NOLSE-NEXT:    ldr w0, [sp, #12] // 4-byte Folded Reload
+; NOLSE-NEXT:    add sp, sp, #32 // =32
+; NOLSE-NEXT:    ret
+;
+; LSE-LABEL: test_rmw_add_32:
+; LSE:       // %bb.0: // %entry
+; LSE-NEXT:    mov w8, #1
+; LSE-NEXT:    ldaddal w8, w0, [x0]
+; LSE-NEXT:    ret
+entry:
+  %res = atomicrmw add i32* %dst, i32 1 seq_cst
+  ret i32 %res
+}
+
+define i64 @test_rmw_add_64(i64* %dst)   {
+; NOLSE-LABEL: test_rmw_add_64:
+; NOLSE:       // %bb.0: // %entry
+; NOLSE-NEXT:    sub sp, sp, #32 // =32
+; NOLSE-NEXT:    .cfi_def_cfa_offset 32
+; NOLSE-NEXT:    str x0, [sp, #16] // 8-byte Folded Spill
+; NOLSE-NEXT:    ldr x8, [x0]
+; NOLSE-NEXT:    str x8, [sp, #24] // 8-byte Folded Spill
+; NOLSE-NEXT:    b .LBB3_1
+; NOLSE-NEXT:  .LBB3_1: // %atomicrmw.start
+; NOLSE-NEXT:    // =>This Loop Header: Depth=1
+; NOLSE-NEXT:    // Child Loop BB3_2 Depth 2
+; NOLSE-NEXT:    ldr x9, [sp, #24] // 8-byte Folded Reload
+; NOLSE-NEXT:    ldr x11, [sp, #16] // 8-byte Folded Reload
+; NOLSE-NEXT:    add x12, x9, #1 // =1
+; NOLSE-NEXT:  .LBB3_2: // %atomicrmw.start
+; NOLSE-NEXT:    // Parent Loop BB3_1 Depth=1
+; NOLSE-NEXT:    // => This Inner Loop Header: Depth=2
+; NOLSE-NEXT:    ldaxr x8, [x11]
+; NOLSE-NEXT:    cmp x8, x9
+; NOLSE-NEXT:    b.ne .LBB3_4
+; NOLSE-NEXT:  // %bb.3: // %atomicrmw.start
+; NOLSE-NEXT:    // in Loop: Header=BB3_2 Depth=2
+; NOLSE-NEXT:    stlxr w10, x12, [x11]
+; NOLSE-NEXT:    cbnz w10, .LBB3_2
+; NOLSE-NEXT:  .LBB3_4: // %atomicrmw.start
+; NOLSE-NEXT:    // in Loop: Header=BB3_1 Depth=1
+; NOLSE-NEXT:    subs x9, x8, x9
+; NOLSE-NEXT:    cset w9, eq
+; NOLSE-NEXT:    str x8, [sp, #8] // 8-byte Folded Spill
+; NOLSE-NEXT:    subs w9, w9, #1 // =1
+; NOLSE-NEXT:    str x8, [sp, #24] // 8-byte Folded Spill
+; NOLSE-NEXT:    b.ne .LBB3_1
+; NOLSE-NEXT:    b .LBB3_5
+; NOLSE-NEXT:  .LBB3_5: // %atomicrmw.end
+; NOLSE-NEXT:    ldr x0, [sp, #8] // 8-byte Folded Reload
+; NOLSE-NEXT:    add sp, sp, #32 // =32
+; NOLSE-NEXT:    ret
+;
+; LSE-LABEL: test_rmw_add_64:
+; LSE:       // %bb.0: // %entry
+; LSE-NEXT:    mov w8, #1
+; LSE-NEXT:    // kill: def $x8 killed $w8
+; LSE-NEXT:    ldaddal x8, x0, [x0]
+; LSE-NEXT:    ret
+entry:
+  %res = atomicrmw add i64* %dst, i64 1 seq_cst
+  ret i64 %res
+}
+
+define i128 @test_rmw_add_128(i128* %dst)   {
+; NOLSE-LABEL: test_rmw_add_128:
+; NOLSE:       // %bb.0: // %entry
+; NOLSE-NEXT:    sub sp, sp, #48 // =48
+; NOLSE-NEXT:    .cfi_def_cfa_offset 48
+; NOLSE-NEXT:    str x0, [sp, #24] // 8-byte Folded Spill
+; NOLSE-NEXT:    ldr x8, [x0, #8]
+; NOLSE-NEXT:    ldr x9, [x0]
+; NOLSE-NEXT:    str x9, [sp, #32] // 8-byte Folded Spill
+; NOLSE-NEXT:    str x8, [sp, #40] // 8-byte Folded Spill
+; NOLSE-NEXT:    b .LBB4_1
+; NOLSE-NEXT:  .LBB4_1: // %atomicrmw.start
+; NOLSE-NEXT:    // =>This Loop Header: Depth=1
+; NOLSE-NEXT:    // Child Loop BB4_2 Depth 2
+; NOLSE-NEXT:    ldr x11, [sp, #40] // 8-byte Folded Reload
+; NOLSE-NEXT:    ldr x8, [sp, #32] // 8-byte Folded Reload
+; NOLSE-NEXT:    ldr x13, [sp, #24] // 8-byte Folded Reload
+; NOLSE-NEXT:    adds x14, x8, #1 // =1
+; NOLSE-NEXT:    mov x9, xzr
+; NOLSE-NEXT:    adcs x15, x11, x9
+; NOLSE-NEXT:  .LBB4_2: // %atomicrmw.start
+; NOLSE-NEXT:    // Parent Loop BB4_1 Depth=1
+; NOLSE-NEXT:    // => This Inner Loop Header: Depth=2
+; NOLSE-NEXT:    ldaxp x10, x9, [x13]
+; NOLSE-NEXT:    cmp x10, x8
+; NOLSE-NEXT:    cset w12, ne
+; NOLSE-NEXT:    cmp x9, x11
+; NOLSE-NEXT:    cinc w12, w12, ne
+; NOLSE-NEXT:    cbnz w12, .LBB4_4
+; NOLSE-NEXT:  // %bb.3: // %atomicrmw.start
+; NOLSE-NEXT:    // in Loop: Header=BB4_2 Depth=2
+; NOLSE-NEXT:    stlxp w12, x14, x15, [x13]
+; NOLSE-NEXT:    cbnz w12, .LBB4_2
+; NOLSE-NEXT:  .LBB4_4: // %atomicrmw.start
+; NOLSE-NEXT:    // in Loop: Header=BB4_1 Depth=1
+; NOLSE-NEXT:    eor x11, x9, x11
+; NOLSE-NEXT:    eor x8, x10, x8
+; NOLSE-NEXT:    orr x8, x8, x11
+; NOLSE-NEXT:    str x9, [sp, #8] // 8-byte Folded Spill
+; NOLSE-NEXT:    str x10, [sp, #16] // 8-byte Folded Spill
+; NOLSE-NEXT:    str x10, [sp, #32] // 8-byte Folded Spill
+; NOLSE-NEXT:    str x9, [sp, #40] // 8-byte Folded Spill
+; NOLSE-NEXT:    cbnz x8, .LBB4_1
+; NOLSE-NEXT:    b .LBB4_5
+; NOLSE-NEXT:  .LBB4_5: // %atomicrmw.end
+; NOLSE-NEXT:    ldr x1, [sp, #8] // 8-byte Folded Reload
+; NOLSE-NEXT:    ldr x0, [sp, #16] // 8-byte Folded Reload
+; NOLSE-NEXT:    add sp, sp, #48 // =48
+; NOLSE-NEXT:    ret
+;
+; LSE-LABEL: test_rmw_add_128:
+; LSE:       // %bb.0: // %entry
+; LSE-NEXT:    sub sp, sp, #80 // =80
+; LSE-NEXT:    .cfi_def_cfa_offset 80
+; LSE-NEXT:    str x0, [sp, #56] // 8-byte Folded Spill
+; LSE-NEXT:    ldr x8, [x0, #8]
+; LSE-NEXT:    ldr x9, [x0]
+; LSE-NEXT:    str x9, [sp, #64] // 8-byte Folded Spill
+; LSE-NEXT:    str x8, [sp, #72] // 8-byte Folded Spill
+; LSE-NEXT:    b .LBB4_1
+; LSE-NEXT:  .LBB4_1: // %atomicrmw.start
+; LSE-NEXT:    // =>This Inner Loop Header: Depth=1
+; LSE-NEXT:    ldr x10, [sp, #72] // 8-byte Folded Reload
+; LSE-NEXT:    ldr x8, [sp, #64] // 8-byte Folded Reload
+; LSE-NEXT:    ldr x9, [sp, #56] // 8-byte Folded Reload
+; LSE-NEXT:    adds x2, x8, #1 // =1
+; LSE-NEXT:    mov x11, xzr
+; LSE-NEXT:    adcs x11, x10, x11
+; LSE-NEXT:    // kill: def $x2 killed $x2 def $x2_x3
+; LSE-NEXT:    mov x3, x11
+; LSE-NEXT:    mov x0, x8
+; LSE-NEXT:    mov x1, x10
+; LSE-NEXT:    stp x0, x1, [sp, #8] // 16-byte Folded Spill
+; LSE-NEXT:    caspal x0, x1, x2, x3, [x9]
+; LSE-NEXT:    stp x0, x1, [sp, #24] // 16-byte Folded Spill
+; LSE-NEXT:    mov x9, x1
+; LSE-NEXT:    str x9, [sp, #40] // 8-byte Folded Spill
+; LSE-NEXT:    eor x11, x9, x10
+; LSE-NEXT:    mov x10, x0
+; LSE-NEXT:    str x10, [sp, #48] // 8-byte Folded Spill
+; LSE-NEXT:    eor x8, x10, x8
+; LSE-NEXT:    orr x8, x8, x11
+; LSE-NEXT:    str x10, [sp, #64] // 8-byte Folded Spill
+; LSE-NEXT:    str x9, [sp, #72] // 8-byte Folded Spill
+; LSE-NEXT:    cbnz x8, .LBB4_1
+; LSE-NEXT:    b .LBB4_2
+; LSE-NEXT:  .LBB4_2: // %atomicrmw.end
+; LSE-NEXT:    ldr x1, [sp, #40] // 8-byte Folded Reload
+; LSE-NEXT:    ldr x0, [sp, #48] // 8-byte Folded Reload
+; LSE-NEXT:    add sp, sp, #80 // =80
+; LSE-NEXT:    ret
+entry:
+  %res = atomicrmw add i128* %dst, i128 1 seq_cst
+  ret i128 %res
+}
+define i8 @test_rmw_nand_8(i8* %dst)   {
+; NOLSE-LABEL: test_rmw_nand_8:
+; NOLSE:       // %bb.0: // %entry
+; NOLSE-NEXT:    sub sp, sp, #32 // =32
+; NOLSE-NEXT:    .cfi_def_cfa_offset 32
+; NOLSE-NEXT:    str x0, [sp, #16] // 8-byte Folded Spill
+; NOLSE-NEXT:    ldrb w8, [x0]
+; NOLSE-NEXT:    str w8, [sp, #28] // 4-byte Folded Spill
+; NOLSE-NEXT:    b .LBB5_1
+; NOLSE-NEXT:  .LBB5_1: // %atomicrmw.start
+; NOLSE-NEXT:    // =>This Loop Header: Depth=1
+; NOLSE-NEXT:    // Child Loop BB5_2 Depth 2
+; NOLSE-NEXT:    ldr w9, [sp, #28] // 4-byte Folded Reload
+; NOLSE-NEXT:    ldr x11, [sp, #16] // 8-byte Folded Reload
+; NOLSE-NEXT:    mvn w8, w9
+; NOLSE-NEXT:    orr w12, w8, #0xfffffffe
+; NOLSE-NEXT:  .LBB5_2: // %atomicrmw.start
+; NOLSE-NEXT:    // Parent Loop BB5_1 Depth=1
+; NOLSE-NEXT:    // => This Inner Loop Header: Depth=2
+; NOLSE-NEXT:    ldaxrb w8, [x11]
+; NOLSE-NEXT:    cmp w8, w9, uxtb
+; NOLSE-NEXT:    b.ne .LBB5_4
+; NOLSE-NEXT:  // %bb.3: // %atomicrmw.start
+; NOLSE-NEXT:    // in Loop: Header=BB5_2 Depth=2
+; NOLSE-NEXT:    stlxrb w10, w12, [x11]
+; NOLSE-NEXT:    cbnz w10, .LBB5_2
+; NOLSE-NEXT:  .LBB5_4: // %atomicrmw.start
+; NOLSE-NEXT:    // in Loop: Header=BB5_1 Depth=1
+; NOLSE-NEXT:    subs w9, w8, w9, uxtb
+; NOLSE-NEXT:    cset w9, eq
+; NOLSE-NEXT:    str w8, [sp, #12] // 4-byte Folded Spill
+; NOLSE-NEXT:    subs w9, w9, #1 // =1
+; NOLSE-NEXT:    str w8, [sp, #28] // 4-byte Folded Spill
+; NOLSE-NEXT:    b.ne .LBB5_1
+; NOLSE-NEXT:    b .LBB5_5
+; NOLSE-NEXT:  .LBB5_5: // %atomicrmw.end
+; NOLSE-NEXT:    ldr w0, [sp, #12] // 4-byte Folded Reload
+; NOLSE-NEXT:    add sp, sp, #32 // =32
+; NOLSE-NEXT:    ret
+;
+; LSE-LABEL: test_rmw_nand_8:
+; LSE:       // %bb.0: // %entry
+; LSE-NEXT:    sub sp, sp, #32 // =32
+; LSE-NEXT:    .cfi_def_cfa_offset 32
+; LSE-NEXT:    str x0, [sp, #16] // 8-byte Folded Spill
+; LSE-NEXT:    ldrb w8, [x0]
+; LSE-NEXT:    str w8, [sp, #28] // 4-byte Folded Spill
+; LSE-NEXT:    b .LBB5_1
+; LSE-NEXT:  .LBB5_1: // %atomicrmw.start
+; LSE-NEXT:    // =>This Inner Loop Header: Depth=1
+; LSE-NEXT:    ldr w9, [sp, #28] // 4-byte Folded Reload
+; LSE-NEXT:    ldr x11, [sp, #16] // 8-byte Folded Reload
+; LSE-NEXT:    mvn w8, w9
+; LSE-NEXT:    orr w10, w8, #0xfffffffe
+; LSE-NEXT:    mov w8, w9
+; LSE-NEXT:    casalb w8, w10, [x11]
+; LSE-NEXT:    str w8, [sp, #8] // 4-byte Folded Spill
+; LSE-NEXT:    subs w9, w8, w9, uxtb
+; LSE-NEXT:    cset w9, eq
+; LSE-NEXT:    str w8, [sp, #12] // 4-byte Folded Spill
+; LSE-NEXT:    subs w9, w9, #1 // =1
+; LSE-NEXT:    str w8, [sp, #28] // 4-byte Folded Spill
+; LSE-NEXT:    b.ne .LBB5_1
+; LSE-NEXT:    b .LBB5_2
+; LSE-NEXT:  .LBB5_2: // %atomicrmw.end
+; LSE-NEXT:    ldr w0, [sp, #12] // 4-byte Folded Reload
+; LSE-NEXT:    add sp, sp, #32 // =32
+; LSE-NEXT:    ret
+entry:
+  %res = atomicrmw nand i8* %dst, i8 1 seq_cst
+  ret i8 %res
+}
+
+define i16 @test_rmw_nand_16(i16* %dst)   {
+; NOLSE-LABEL: test_rmw_nand_16:
+; NOLSE:       // %bb.0: // %entry
+; NOLSE-NEXT:    sub sp, sp, #32 // =32
+; NOLSE-NEXT:    .cfi_def_cfa_offset 32
+; NOLSE-NEXT:    str x0, [sp, #16] // 8-byte Folded Spill
+; NOLSE-NEXT:    ldrh w8, [x0]
+; NOLSE-NEXT:    str w8, [sp, #28] // 4-byte Folded Spill
+; NOLSE-NEXT:    b .LBB6_1
+; NOLSE-NEXT:  .LBB6_1: // %atomicrmw.start
+; NOLSE-NEXT:    // =>This Loop Header: Depth=1
+; NOLSE-NEXT:    // Child Loop BB6_2 Depth 2
+; NOLSE-NEXT:    ldr w9, [sp, #28] // 4-byte Folded Reload
+; NOLSE-NEXT:    ldr x11, [sp, #16] // 8-byte Folded Reload
+; NOLSE-NEXT:    mvn w8, w9
+; NOLSE-NEXT:    orr w12, w8, #0xfffffffe
+; NOLSE-NEXT:  .LBB6_2: // %atomicrmw.start
+; NOLSE-NEXT:    // Parent Loop BB6_1 Depth=1
+; NOLSE-NEXT:    // => This Inner Loop Header: Depth=2
+; NOLSE-NEXT:    ldaxrh w8, [x11]
+; NOLSE-NEXT:    cmp w8, w9, uxth
+; NOLSE-NEXT:    b.ne .LBB6_4
+; NOLSE-NEXT:  // %bb.3: // %atomicrmw.start
+; NOLSE-NEXT:    // in Loop: Header=BB6_2 Depth=2
+; NOLSE-NEXT:    stlxrh w10, w12, [x11]
+; NOLSE-NEXT:    cbnz w10, .LBB6_2
+; NOLSE-NEXT:  .LBB6_4: // %atomicrmw.start
+; NOLSE-NEXT:    // in Loop: Header=BB6_1 Depth=1
+; NOLSE-NEXT:    subs w9, w8, w9, uxth
+; NOLSE-NEXT:    cset w9, eq
+; NOLSE-NEXT:    str w8, [sp, #12] // 4-byte Folded Spill
+; NOLSE-NEXT:    subs w9, w9, #1 // =1
+; NOLSE-NEXT:    str w8, [sp, #28] // 4-byte Folded Spill
+; NOLSE-NEXT:    b.ne .LBB6_1
+; NOLSE-NEXT:    b .LBB6_5
+; NOLSE-NEXT:  .LBB6_5: // %atomicrmw.end
+; NOLSE-NEXT:    ldr w0, [sp, #12] // 4-byte Folded Reload
+; NOLSE-NEXT:    add sp, sp, #32 // =32
+; NOLSE-NEXT:    ret
+;
+; LSE-LABEL: test_rmw_nand_16:
+; LSE:       // %bb.0: // %entry
+; LSE-NEXT:    sub sp, sp, #32 // =32
+; LSE-NEXT:    .cfi_def_cfa_offset 32
+; LSE-NEXT:    str x0, [sp, #16] // 8-byte Folded Spill
+; LSE-NEXT:    ldrh w8, [x0]
+; LSE-NEXT:    str w8, [sp, #28] // 4-byte Folded Spill
+; LSE-NEXT:    b .LBB6_1
+; LSE-NEXT:  .LBB6_1: // %atomicrmw.start
+; LSE-NEXT:    // =>This Inner Loop Header: Depth=1
+; LSE-NEXT:    ldr w9, [sp, #28] // 4-byte Folded Reload
+; LSE-NEXT:    ldr x11, [sp, #16] // 8-byte Folded Reload
+; LSE-NEXT:    mvn w8, w9
+; LSE-NEXT:    orr w10, w8, #0xfffffffe
+; LSE-NEXT:    mov w8, w9
+; LSE-NEXT:    casalh w8, w10, [x11]
+; LSE-NEXT:    str w8, [sp, #8] // 4-byte Folded Spill
+; LSE-NEXT:    subs w9, w8, w9, uxth
+; LSE-NEXT:    cset w9, eq
+; LSE-NEXT:    str w8, [sp, #12] // 4-byte Folded Spill
+; LSE-NEXT:    subs w9, w9, #1 // =1
+; LSE-NEXT:    str w8, [sp, #28] // 4-byte Folded Spill
+; LSE-NEXT:    b.ne .LBB6_1
+; LSE-NEXT:    b .LBB6_2
+; LSE-NEXT:  .LBB6_2: // %atomicrmw.end
+; LSE-NEXT:    ldr w0, [sp, #12] // 4-byte Folded Reload
+; LSE-NEXT:    add sp, sp, #32 // =32
+; LSE-NEXT:    ret
+entry:
+  %res = atomicrmw nand i16* %dst, i16 1 seq_cst
+  ret i16 %res
+}
+
+define i32 @test_rmw_nand_32(i32* %dst)   {
+; NOLSE-LABEL: test_rmw_nand_32:
+; NOLSE:       // %bb.0: // %entry
+; NOLSE-NEXT:    sub sp, sp, #32 // =32
+; NOLSE-NEXT:    .cfi_def_cfa_offset 32
+; NOLSE-NEXT:    str x0, [sp, #16] // 8-byte Folded Spill
+; NOLSE-NEXT:    ldr w8, [x0]
+; NOLSE-NEXT:    str w8, [sp, #28] // 4-byte Folded Spill
+; NOLSE-NEXT:    b .LBB7_1
+; NOLSE-NEXT:  .LBB7_1: // %atomicrmw.start
+; NOLSE-NEXT:    // =>This Loop Header: Depth=1
+; NOLSE-NEXT:    // Child Loop BB7_2 Depth 2
+; NOLSE-NEXT:    ldr w9, [sp, #28] // 4-byte Folded Reload
+; NOLSE-NEXT:    ldr x11, [sp, #16] // 8-byte Folded Reload
+; NOLSE-NEXT:    mvn w8, w9
+; NOLSE-NEXT:    orr w12, w8, #0xfffffffe
+; NOLSE-NEXT:  .LBB7_2: // %atomicrmw.start
+; NOLSE-NEXT:    // Parent Loop BB7_1 Depth=1
+; NOLSE-NEXT:    // => This Inner Loop Header: Depth=2
+; NOLSE-NEXT:    ldaxr w8, [x11]
+; NOLSE-NEXT:    cmp w8, w9
+; NOLSE-NEXT:    b.ne .LBB7_4
+; NOLSE-NEXT:  // %bb.3: // %atomicrmw.start
+; NOLSE-NEXT:    // in Loop: Header=BB7_2 Depth=2
+; NOLSE-NEXT:    stlxr w10, w12, [x11]
+; NOLSE-NEXT:    cbnz w10, .LBB7_2
+; NOLSE-NEXT:  .LBB7_4: // %atomicrmw.start
+; NOLSE-NEXT:    // in Loop: Header=BB7_1 Depth=1
+; NOLSE-NEXT:    subs w9, w8, w9
+; NOLSE-NEXT:    cset w9, eq
+; NOLSE-NEXT:    str w8, [sp, #12] // 4-byte Folded Spill
+; NOLSE-NEXT:    subs w9, w9, #1 // =1
+; NOLSE-NEXT:    str w8, [sp, #28] // 4-byte Folded Spill
+; NOLSE-NEXT:    b.ne .LBB7_1
+; NOLSE-NEXT:    b .LBB7_5
+; NOLSE-NEXT:  .LBB7_5: // %atomicrmw.end
+; NOLSE-NEXT:    ldr w0, [sp, #12] // 4-byte Folded Reload
+; NOLSE-NEXT:    add sp, sp, #32 // =32
+; NOLSE-NEXT:    ret
+;
+; LSE-LABEL: test_rmw_nand_32:
+; LSE:       // %bb.0: // %entry
+; LSE-NEXT:    sub sp, sp, #32 // =32
+; LSE-NEXT:    .cfi_def_cfa_offset 32
+; LSE-NEXT:    str x0, [sp, #16] // 8-byte Folded Spill
+; LSE-NEXT:    ldr w8, [x0]
+; LSE-NEXT:    str w8, [sp, #28] // 4-byte Folded Spill
+; LSE-NEXT:    b .LBB7_1
+; LSE-NEXT:  .LBB7_1: // %atomicrmw.start
+; LSE-NEXT:    // =>This Inner Loop Header: Depth=1
+; LSE-NEXT:    ldr w9, [sp, #28] // 4-byte Folded Reload
+; LSE-NEXT:    ldr x11, [sp, #16] // 8-byte Folded Reload
+; LSE-NEXT:    mvn w8, w9
+; LSE-NEXT:    orr w10, w8, #0xfffffffe
+; LSE-NEXT:    mov w8, w9
+; LSE-NEXT:    casal w8, w10, [x11]
+; LSE-NEXT:    str w8, [sp, #8] // 4-byte Folded Spill
+; LSE-NEXT:    subs w9, w8, w9
+; LSE-NEXT:    cset w9, eq
+; LSE-NEXT:    str w8, [sp, #12] // 4-byte Folded Spill
+; LSE-NEXT:    subs w9, w9, #1 // =1
+; LSE-NEXT:    str w8, [sp, #28] // 4-byte Folded Spill
+; LSE-NEXT:    b.ne .LBB7_1
+; LSE-NEXT:    b .LBB7_2
+; LSE-NEXT:  .LBB7_2: // %atomicrmw.end
+; LSE-NEXT:    ldr w0, [sp, #12] // 4-byte Folded Reload
+; LSE-NEXT:    add sp, sp, #32 // =32
+; LSE-NEXT:    ret
+entry:
+  %res = atomicrmw nand i32* %dst, i32 1 seq_cst
+  ret i32 %res
+}
+
+define i64 @test_rmw_nand_64(i64* %dst)   {
+; NOLSE-LABEL: test_rmw_nand_64:
+; NOLSE:       // %bb.0: // %entry
+; NOLSE-NEXT:    sub sp, sp, #32 // =32
+; NOLSE-NEXT:    .cfi_def_cfa_offset 32
+; NOLSE-NEXT:    str x0, [sp, #16] // 8-byte Folded Spill
+; NOLSE-NEXT:    ldr x8, [x0]
+; NOLSE-NEXT:    str x8, [sp, #24] // 8-byte Folded Spill
+; NOLSE-NEXT:    b .LBB8_1
+; NOLSE-NEXT:  .LBB8_1: // %atomicrmw.start
+; NOLSE-NEXT:    // =>This Loop Header: Depth=1
+; NOLSE-NEXT:    // Child Loop BB8_2 Depth 2
+; NOLSE-NEXT:    ldr x9, [sp, #24] // 8-byte Folded Reload
+; NOLSE-NEXT:    ldr x11, [sp, #16] // 8-byte Folded Reload
+; NOLSE-NEXT:    mov w8, w9
+; NOLSE-NEXT:    mvn w10, w8
+; NOLSE-NEXT:    // implicit-def: $x8
+; NOLSE-NEXT:    mov w8, w10
+; NOLSE-NEXT:    orr x12, x8, #0xfffffffffffffffe
+; NOLSE-NEXT:  .LBB8_2: // %atomicrmw.start
+; NOLSE-NEXT:    // Parent Loop BB8_1 Depth=1
+; NOLSE-NEXT:    // => This Inner Loop Header: Depth=2
+; NOLSE-NEXT:    ldaxr x8, [x11]
+; NOLSE-NEXT:    cmp x8, x9
+; NOLSE-NEXT:    b.ne .LBB8_4
+; NOLSE-NEXT:  // %bb.3: // %atomicrmw.start
+; NOLSE-NEXT:    // in Loop: Header=BB8_2 Depth=2
+; NOLSE-NEXT:    stlxr w10, x12, [x11]
+; NOLSE-NEXT:    cbnz w10, .LBB8_2
+; NOLSE-NEXT:  .LBB8_4: // %atomicrmw.start
+; NOLSE-NEXT:    // in Loop: Header=BB8_1 Depth=1
+; NOLSE-NEXT:    subs x9, x8, x9
+; NOLSE-NEXT:    cset w9, eq
+; NOLSE-NEXT:    str x8, [sp, #8] // 8-byte Folded Spill
+; NOLSE-NEXT:    subs w9, w9, #1 // =1
+; NOLSE-NEXT:    str x8, [sp, #24] // 8-byte Folded Spill
+; NOLSE-NEXT:    b.ne .LBB8_1
+; NOLSE-NEXT:    b .LBB8_5
+; NOLSE-NEXT:  .LBB8_5: // %atomicrmw.end
+; NOLSE-NEXT:    ldr x0, [sp, #8] // 8-byte Folded Reload
+; NOLSE-NEXT:    add sp, sp, #32 // =32
+; NOLSE-NEXT:    ret
+;
+; LSE-LABEL: test_rmw_nand_64:
+; LSE:       // %bb.0: // %entry
+; LSE-NEXT:    sub sp, sp, #32 // =32
+; LSE-NEXT:    .cfi_def_cfa_offset 32
+; LSE-NEXT:    str x0, [sp, #16] // 8-byte Folded Spill
+; LSE-NEXT:    ldr x8, [x0]
+; LSE-NEXT:    str x8, [sp, #24] // 8-byte Folded Spill
+; LSE-NEXT:    b .LBB8_1
+; LSE-NEXT:  .LBB8_1: // %atomicrmw.start
+; LSE-NEXT:    // =>This Inner Loop Header: Depth=1
+; LSE-NEXT:    ldr x9, [sp, #24] // 8-byte Folded Reload
+; LSE-NEXT:    ldr x11, [sp, #16] // 8-byte Folded Reload
+; LSE-NEXT:    mov w8, w9
+; LSE-NEXT:    mvn w10, w8
+; LSE-NEXT:    // implicit-def: $x8
+; LSE-NEXT:    mov w8, w10
+; LSE-NEXT:    orr x10, x8, #0xfffffffffffffffe
+; LSE-NEXT:    mov x8, x9
+; LSE-NEXT:    casal x8, x10, [x11]
+; LSE-NEXT:    str x8, [sp] // 8-byte Folded Spill
+; LSE-NEXT:    subs x9, x8, x9
+; LSE-NEXT:    cset w9, eq
+; LSE-NEXT:    str x8, [sp, #8] // 8-byte Folded Spill
+; LSE-NEXT:    subs w9, w9, #1 // =1
+; LSE-NEXT:    str x8, [sp, #24] // 8-byte Folded Spill
+; LSE-NEXT:    b.ne .LBB8_1
+; LSE-NEXT:    b .LBB8_2
+; LSE-NEXT:  .LBB8_2: // %atomicrmw.end
+; LSE-NEXT:    ldr x0, [sp, #8] // 8-byte Folded Reload
+; LSE-NEXT:    add sp, sp, #32 // =32
+; LSE-NEXT:    ret
+entry:
+  %res = atomicrmw nand i64* %dst, i64 1 seq_cst
+  ret i64 %res
+}
+
+define i128 @test_rmw_nand_128(i128* %dst)   {
+; NOLSE-LABEL: test_rmw_nand_128:
+; NOLSE:       // %bb.0: // %entry
+; NOLSE-NEXT:    sub sp, sp, #48 // =48
+; NOLSE-NEXT:    .cfi_def_cfa_offset 48
+; NOLSE-NEXT:    str x0, [sp, #24] // 8-byte Folded Spill
+; NOLSE-NEXT:    ldr x8, [x0, #8]
+; NOLSE-NEXT:    ldr x9, [x0]
+; NOLSE-NEXT:    str x9, [sp, #32] // 8-byte Folded Spill
+; NOLSE-NEXT:    str x8, [sp, #40] // 8-byte Folded Spill
+; NOLSE-NEXT:    b .LBB9_1
+; NOLSE-NEXT:  .LBB9_1: // %atomicrmw.start
+; NOLSE-NEXT:    // =>This Loop Header: Depth=1
+; NOLSE-NEXT:    // Child Loop BB9_2 Depth 2
+; NOLSE-NEXT:    ldr x11, [sp, #40] // 8-byte Folded Reload
+; NOLSE-NEXT:    ldr x8, [sp, #32] // 8-byte Folded Reload
+; NOLSE-NEXT:    ldr x13, [sp, #24] // 8-byte Folded Reload
+; NOLSE-NEXT:    mov w9, w8
+; NOLSE-NEXT:    mvn w10, w9
+; NOLSE-NEXT:    // implicit-def: $x9
+; NOLSE-NEXT:    mov w9, w10
+; NOLSE-NEXT:    orr x14, x9, #0xfffffffffffffffe
+; NOLSE-NEXT:    mov x15, #-1
+; NOLSE-NEXT:  .LBB9_2: // %atomicrmw.start
+; NOLSE-NEXT:    // Parent Loop BB9_1 Depth=1
+; NOLSE-NEXT:    // => This Inner Loop Header: Depth=2
+; NOLSE-NEXT:    ldaxp x10, x9, [x13]
+; NOLSE-NEXT:    cmp x10, x8
+; NOLSE-NEXT:    cset w12, ne
+; NOLSE-NEXT:    cmp x9, x11
+; NOLSE-NEXT:    cinc w12, w12, ne
+; NOLSE-NEXT:    cbnz w12, .LBB9_4
+; NOLSE-NEXT:  // %bb.3: // %atomicrmw.start
+; NOLSE-NEXT:    // in Loop: Header=BB9_2 Depth=2
+; NOLSE-NEXT:    stlxp w12, x14, x15, [x13]
+; NOLSE-NEXT:    cbnz w12, .LBB9_2
+; NOLSE-NEXT:  .LBB9_4: // %atomicrmw.start
+; NOLSE-NEXT:    // in Loop: Header=BB9_1 Depth=1
+; NOLSE-NEXT:    eor x11, x9, x11
+; NOLSE-NEXT:    eor x8, x10, x8
+; NOLSE-NEXT:    orr x8, x8, x11
+; NOLSE-NEXT:    str x9, [sp, #8] // 8-byte Folded Spill
+; NOLSE-NEXT:    str x10, [sp, #16] // 8-byte Folded Spill
+; NOLSE-NEXT:    str x10, [sp, #32] // 8-byte Folded Spill
+; NOLSE-NEXT:    str x9, [sp, #40] // 8-byte Folded Spill
+; NOLSE-NEXT:    cbnz x8, .LBB9_1
+; NOLSE-NEXT:    b .LBB9_5
+; NOLSE-NEXT:  .LBB9_5: // %atomicrmw.end
+; NOLSE-NEXT:    ldr x1, [sp, #8] // 8-byte Folded Reload
+; NOLSE-NEXT:    ldr x0, [sp, #16] // 8-byte Folded Reload
+; NOLSE-NEXT:    add sp, sp, #48 // =48
+; NOLSE-NEXT:    ret
+;
+; LSE-LABEL: test_rmw_nand_128:
+; LSE:       // %bb.0: // %entry
+; LSE-NEXT:    sub sp, sp, #80 // =80
+; LSE-NEXT:    .cfi_def_cfa_offset 80
+; LSE-NEXT:    str x0, [sp, #56] // 8-byte Folded Spill
+; LSE-NEXT:    ldr x8, [x0, #8]
+; LSE-NEXT:    ldr x9, [x0]
+; LSE-NEXT:    str x9, [sp, #64] // 8-byte Folded Spill
+; LSE-NEXT:    str x8, [sp, #72] // 8-byte Folded Spill
+; LSE-NEXT:    b .LBB9_1
+; LSE-NEXT:  .LBB9_1: // %atomicrmw.start
+; LSE-NEXT:    // =>This Inner Loop Header: Depth=1
+; LSE-NEXT:    ldr x10, [sp, #72] // 8-byte Folded Reload
+; LSE-NEXT:    ldr x8, [sp, #64] // 8-byte Folded Reload
+; LSE-NEXT:    ldr x9, [sp, #56] // 8-byte Folded Reload
+; LSE-NEXT:    mov x0, x8
+; LSE-NEXT:    mov x1, x10
+; LSE-NEXT:    stp x0, x1, [sp, #8] // 16-byte Folded Spill
+; LSE-NEXT:    mov w11, w8
+; LSE-NEXT:    mvn w12, w11
+; LSE-NEXT:    // implicit-def: $x11
+; LSE-NEXT:    mov w11, w12
+; LSE-NEXT:    orr x2, x11, #0xfffffffffffffffe
+; LSE-NEXT:    mov x11, #-1
+; LSE-NEXT:    // kill: def $x2 killed $x2 def $x2_x3
+; LSE-NEXT:    mov x3, x11
+; LSE-NEXT:    caspal x0, x1, x2, x3, [x9]
+; LSE-NEXT:    stp x0, x1, [sp, #24] // 16-byte Folded Spill
+; LSE-NEXT:    mov x9, x1
+; LSE-NEXT:    str x9, [sp, #40] // 8-byte Folded Spill
+; LSE-NEXT:    eor x11, x9, x10
+; LSE-NEXT:    mov x10, x0
+; LSE-NEXT:    str x10, [sp, #48] // 8-byte Folded Spill
+; LSE-NEXT:    eor x8, x10, x8
+; LSE-NEXT:    orr x8, x8, x11
+; LSE-NEXT:    str x10, [sp, #64] // 8-byte Folded Spill
+; LSE-NEXT:    str x9, [sp, #72] // 8-byte Folded Spill
+; LSE-NEXT:    cbnz x8, .LBB9_1
+; LSE-NEXT:    b .LBB9_2
+; LSE-NEXT:  .LBB9_2: // %atomicrmw.end
+; LSE-NEXT:    ldr x1, [sp, #40] // 8-byte Folded Reload
+; LSE-NEXT:    ldr x0, [sp, #48] // 8-byte Folded Reload
+; LSE-NEXT:    add sp, sp, #80 // =80
+; LSE-NEXT:    ret
+entry:
+  %res = atomicrmw nand i128* %dst, i128 1 seq_cst
+  ret i128 %res
+}
diff --git a/llvm/test/Transforms/AtomicExpand/AArch64/expand-atomicrmw-xchg-fp.ll b/llvm/test/Transforms/AtomicExpand/AArch64/expand-atomicrmw-xchg-fp.ll
--- a/llvm/test/Transforms/AtomicExpand/AArch64/expand-atomicrmw-xchg-fp.ll
+++ b/llvm/test/Transforms/AtomicExpand/AArch64/expand-atomicrmw-xchg-fp.ll
@@ -1,6 +1,6 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt -S -mtriple=aarch64-- -atomic-expand %s | FileCheck %s
-; RUN: opt -S -mtriple=aarch64-- -mattr=+outline-atomics -atomic-expand %s | FileCheck %s --check-prefix=OUTLINE-ATOMICS
+; RUN: opt -O1 -S -mtriple=aarch64-- -atomic-expand %s | FileCheck %s
+; RUN: opt -O1 -S -mtriple=aarch64-- -mattr=+outline-atomics -atomic-expand %s | FileCheck %s --check-prefix=OUTLINE-ATOMICS
 
 define void @atomic_swap_f16(half* %ptr, half %val) nounwind {
 ; CHECK-LABEL: @atomic_swap_f16(