diff --git a/llvm/lib/Target/ARM/MVEGatherScatterLowering.cpp b/llvm/lib/Target/ARM/MVEGatherScatterLowering.cpp
--- a/llvm/lib/Target/ARM/MVEGatherScatterLowering.cpp
+++ b/llvm/lib/Target/ARM/MVEGatherScatterLowering.cpp
@@ -1167,6 +1167,8 @@
   bool Changed = false;
 
   for (BasicBlock &BB : F) {
+    SimplifyInstructionsInBlock(&BB);
+
     for (Instruction &I : BB) {
       IntrinsicInst *II = dyn_cast<IntrinsicInst>(&I);
       if (II && II->getIntrinsicID() == Intrinsic::masked_gather &&
diff --git a/llvm/test/CodeGen/Thumb2/LowOverheadLoops/remat-vctp.ll b/llvm/test/CodeGen/Thumb2/LowOverheadLoops/remat-vctp.ll
--- a/llvm/test/CodeGen/Thumb2/LowOverheadLoops/remat-vctp.ll
+++ b/llvm/test/CodeGen/Thumb2/LowOverheadLoops/remat-vctp.ll
@@ -1,5 +1,5 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
-; RUN: llc -mtriple=thumbv8.1m.main -mattr=+mve.fp %s -o - | FileCheck %s
+; RUN: llc -mtriple=thumbv8.1m.main -mattr=+mve.fp -enable-arm-maskedgatscat=false %s -o - | FileCheck %s
 
 define void @remat_vctp(i32* %arg, i32* %arg1, i32* %arg2, i32* %arg3, i32* %arg4, i16 zeroext %arg5) {
 ; CHECK-LABEL: remat_vctp:
diff --git a/llvm/test/CodeGen/Thumb2/lsll0.ll b/llvm/test/CodeGen/Thumb2/lsll0.ll
--- a/llvm/test/CodeGen/Thumb2/lsll0.ll
+++ b/llvm/test/CodeGen/Thumb2/lsll0.ll
@@ -1,5 +1,5 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
-; RUN: llc -mtriple=thumbv8.1m.main-none-none-eabi -mattr=+mve -verify-machineinstrs %s -o - | FileCheck %s
+; RUN: llc -mtriple=thumbv8.1m.main-none-none-eabi -mattr=+mve -enable-arm-maskedgatscat=false -verify-machineinstrs %s -o - | FileCheck %s
 
 define void @_Z4loopPxS_iS_i(i64* %d) {
 ; CHECK-LABEL: _Z4loopPxS_iS_i:
diff --git a/llvm/test/CodeGen/Thumb2/mve-gather-scatter-optimisation.ll b/llvm/test/CodeGen/Thumb2/mve-gather-scatter-optimisation.ll
--- a/llvm/test/CodeGen/Thumb2/mve-gather-scatter-optimisation.ll
+++ b/llvm/test/CodeGen/Thumb2/mve-gather-scatter-optimisation.ll
@@ -321,26 +321,29 @@
   ret void;
 }
 
-define arm_aapcs_vfpcc void @non_gatscat_use1(i32* noalias nocapture readonly %data, i32* noalias nocapture %dst, i32 %n.vec) {
+define arm_aapcs_vfpcc void @non_gatscat_use1(i32* noalias nocapture readonly %data, i32* noalias nocapture %dst, i32 %n.vec, <4 x i32>* %x) {
 ; CHECK-LABEL: non_gatscat_use1:
 ; CHECK:       @ %bb.0: @ %vector.ph
-; CHECK-NEXT:    .vsave {d8, d9}
-; CHECK-NEXT:    vpush {d8, d9}
-; CHECK-NEXT:    adr r3, .LCPI7_0
-; CHECK-NEXT:    vmov.i32 q0, #0x8
-; CHECK-NEXT:    vldrw.u32 q2, [r3]
+; CHECK-NEXT:    .vsave {d8, d9, d10, d11, d12, d13}
+; CHECK-NEXT:    vpush {d8, d9, d10, d11, d12, d13}
+; CHECK-NEXT:    adr.w r12, .LCPI7_0
+; CHECK-NEXT:    vmov.i32 q0, #0x9
+; CHECK-NEXT:    vldrw.u32 q3, [r12]
 ; CHECK-NEXT:    vmov.i32 q1, #0xc
+; CHECK-NEXT:    vmov.i32 q2, #0x8
 ; CHECK-NEXT:  .LBB7_1: @ %vector.body
 ; CHECK-NEXT:    @ =>This Inner Loop Header: Depth=1
-; CHECK-NEXT:    vadd.i32 q3, q2, q0
-; CHECK-NEXT:    vmlas.u32 q2, q1, r0
-; CHECK-NEXT:    vldrw.u32 q4, [q2, #24]
+; CHECK-NEXT:    vadd.i32 q4, q3, q2
+; CHECK-NEXT:    vmul.i32 q5, q3, q0
+; CHECK-NEXT:    vmlas.u32 q3, q1, r0
 ; CHECK-NEXT:    subs r2, #4
-; CHECK-NEXT:    vmov q2, q3
-; CHECK-NEXT:    vstrb.8 q4, [r1], #16
+; CHECK-NEXT:    vldrw.u32 q6, [q3, #24]
+; CHECK-NEXT:    vmov q3, q4
+; CHECK-NEXT:    vstrw.32 q5, [r3]
+; CHECK-NEXT:    vstrb.8 q6, [r1], #16
 ; CHECK-NEXT:    bne .LBB7_1
 ; CHECK-NEXT:  @ %bb.2: @ %end
-; CHECK-NEXT:    vpop {d8, d9}
+; CHECK-NEXT:    vpop {d8, d9, d10, d11, d12, d13}
 ; CHECK-NEXT:    bx lr
 ; CHECK-NEXT:    .p2align 4
 ; CHECK-NEXT:  @ %bb.3:
@@ -364,6 +367,7 @@
   %4 = bitcast i32* %3 to <4 x i32>*
   store <4 x i32> %wide.masked.gather, <4 x i32>* %4, align 4
   %non_gatscat_use = mul <4 x i32> %0, <i32 3, i32 3, i32 3, i32 3>
+  store <4 x i32> %non_gatscat_use, <4 x i32>* %x, align 4
   %index.next = add i32 %index, 4
   %vec.ind.next = add <4 x i32> %vec.ind, <i32 8, i32 8, i32 8, i32 8>
   %5 = icmp eq i32 %index.next, %n.vec
@@ -373,26 +377,31 @@
   ret void;
 }
 
-define arm_aapcs_vfpcc void @non_gatscat_use2(i32* noalias nocapture readonly %data, i32* noalias nocapture %dst, i32 %n.vec) {
+define arm_aapcs_vfpcc void @non_gatscat_use2(i32* noalias nocapture readonly %data, i32* noalias nocapture %dst, i32 %n.vec, <4 x i32>* %x) {
 ; CHECK-LABEL: non_gatscat_use2:
 ; CHECK:       @ %bb.0: @ %vector.ph
-; CHECK-NEXT:    .vsave {d8, d9}
-; CHECK-NEXT:    vpush {d8, d9}
-; CHECK-NEXT:    adr r3, .LCPI8_0
-; CHECK-NEXT:    vmov.i32 q0, #0x8
-; CHECK-NEXT:    vldrw.u32 q2, [r3]
-; CHECK-NEXT:    vmov.i32 q1, #0xc
+; CHECK-NEXT:    .vsave {d8, d9, d10, d11, d12, d13, d14, d15}
+; CHECK-NEXT:    vpush {d8, d9, d10, d11, d12, d13, d14, d15}
+; CHECK-NEXT:    adr.w r12, .LCPI8_0
+; CHECK-NEXT:    vmov.i32 q0, #0x12
+; CHECK-NEXT:    vldrw.u32 q4, [r12]
+; CHECK-NEXT:    vmov.i32 q1, #0x9
+; CHECK-NEXT:    vmov.i32 q2, #0x8
+; CHECK-NEXT:    vmov.i32 q3, #0xc
 ; CHECK-NEXT:  .LBB8_1: @ %vector.body
 ; CHECK-NEXT:    @ =>This Inner Loop Header: Depth=1
-; CHECK-NEXT:    vadd.i32 q3, q2, q0
-; CHECK-NEXT:    vmlas.u32 q2, q1, r0
-; CHECK-NEXT:    vldrw.u32 q4, [q2, #24]
+; CHECK-NEXT:    vadd.i32 q5, q4, q2
+; CHECK-NEXT:    vmul.i32 q6, q4, q1
+; CHECK-NEXT:    vmlas.u32 q4, q3, r0
 ; CHECK-NEXT:    subs r2, #4
-; CHECK-NEXT:    vmov q2, q3
-; CHECK-NEXT:    vstrb.8 q4, [r1], #16
+; CHECK-NEXT:    vldrw.u32 q7, [q4, #24]
+; CHECK-NEXT:    vadd.i32 q4, q6, q0
+; CHECK-NEXT:    vstrw.32 q4, [r3]
+; CHECK-NEXT:    vmov q4, q5
+; CHECK-NEXT:    vstrb.8 q7, [r1], #16
 ; CHECK-NEXT:    bne .LBB8_1
 ; CHECK-NEXT:  @ %bb.2: @ %end
-; CHECK-NEXT:    vpop {d8, d9}
+; CHECK-NEXT:    vpop {d8, d9, d10, d11, d12, d13, d14, d15}
 ; CHECK-NEXT:    bx lr
 ; CHECK-NEXT:    .p2align 4
 ; CHECK-NEXT:  @ %bb.3:
@@ -416,6 +425,7 @@
   %4 = bitcast i32* %3 to <4 x i32>*
   store <4 x i32> %wide.masked.gather, <4 x i32>* %4, align 4
   %non_gatscat_use = mul <4 x i32> %1, <i32 3, i32 3, i32 3, i32 3>
+  store <4 x i32> %non_gatscat_use, <4 x i32>* %x, align 4
   %index.next = add i32 %index, 4
   %vec.ind.next = add <4 x i32> %vec.ind, <i32 8, i32 8, i32 8, i32 8>
   %5 = icmp eq i32 %index.next, %n.vec
@@ -849,12 +859,12 @@
 ; CHECK-NEXT:    add.w r8, r7, #10
 ; CHECK-NEXT:    adr r7, .LCPI11_0
 ; CHECK-NEXT:    ldr r1, [sp, #96]
-; CHECK-NEXT:    vdup.32 q1, r2
-; CHECK-NEXT:    vldrw.u32 q0, [r7]
+; CHECK-NEXT:    vdup.32 q0, r2
+; CHECK-NEXT:    vldrw.u32 q1, [r7]
 ; CHECK-NEXT:    mov.w r10, #0
 ; CHECK-NEXT:    mov.w r9, #6
 ; CHECK-NEXT:    movs r6, #11
-; CHECK-NEXT:    vshl.i32 q1, q1, #2
+; CHECK-NEXT:    vshl.i32 q0, q0, #2
 ; CHECK-NEXT:    movs r5, #0
 ; CHECK-NEXT:  .LBB11_1: @ %for.body10.i
 ; CHECK-NEXT:    @ =>This Loop Header: Depth=1
@@ -889,10 +899,10 @@
 ; CHECK-NEXT:    mul r4, r11, r6
 ; CHECK-NEXT:    vdup.32 q3, r5
 ; CHECK-NEXT:    vdup.32 q2, r7
-; CHECK-NEXT:    vadd.i32 q4, q0, r4
+; CHECK-NEXT:    vadd.i32 q4, q1, r4
 ; CHECK-NEXT:    vmla.u32 q3, q4, r2
 ; CHECK-NEXT:    adds r4, #113
-; CHECK-NEXT:    vadd.i32 q4, q0, r4
+; CHECK-NEXT:    vadd.i32 q4, q1, r4
 ; CHECK-NEXT:    mov r4, r8
 ; CHECK-NEXT:    vmla.u32 q2, q4, r2
 ; CHECK-NEXT:  .LBB11_5: @ %vector.body
@@ -902,8 +912,8 @@
 ; CHECK-NEXT:    @ Parent Loop BB11_4 Depth=4
 ; CHECK-NEXT:    @ => This Inner Loop Header: Depth=5
 ; CHECK-NEXT:    vldrb.s32 q6, [r0, q2]
-; CHECK-NEXT:    vadd.i32 q5, q2, q1
-; CHECK-NEXT:    vadd.i32 q4, q3, q1
+; CHECK-NEXT:    vadd.i32 q5, q2, q0
+; CHECK-NEXT:    vadd.i32 q4, q3, q0
 ; CHECK-NEXT:    subs r4, #4
 ; CHECK-NEXT:    vadd.i32 q2, q6, r2
 ; CHECK-NEXT:    vldrb.s32 q6, [r1, q3]
diff --git a/llvm/test/CodeGen/Thumb2/mve-gather-unused.ll b/llvm/test/CodeGen/Thumb2/mve-gather-unused.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/CodeGen/Thumb2/mve-gather-unused.ll
@@ -0,0 +1,38 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -mtriple=thumbv8.1m.main-none-none-eabi -mattr=+mve.fp -enable-arm-maskedldst %s -o - | FileCheck %s
+
+; This files has some unused gathers, making sure that they do not cause
+; problems as the function gets simplified.
+
+define arm_aapcs_vfpcc void @unused1(<4 x i32*> %offs) {
+; CHECK-LABEL: unused1:
+; CHECK:       @ %bb.0: @ %entry
+; CHECK-NEXT:    bx lr
+entry:
+  %gather = call <4 x i32> @llvm.masked.gather.v4i32.v4p0i32(<4 x i32*> %offs, i32 4, <4 x i1> <i1 true, i1 true, i1 true, i1 true>, <4 x i32> undef)
+  ret void
+}
+
+define arm_aapcs_vfpcc void @unused2(<4 x i32*> %offs) {
+; CHECK-LABEL: unused2:
+; CHECK:       @ %bb.0: @ %entry
+; CHECK-NEXT:    bx lr
+entry:
+  %gather1 = call <4 x i32> @llvm.masked.gather.v4i32.v4p0i32(<4 x i32*> %offs, i32 4, <4 x i1> <i1 true, i1 true, i1 true, i1 true>, <4 x i32> undef)
+  %gather2 = call <4 x i32> @llvm.masked.gather.v4i32.v4p0i32(<4 x i32*> %offs, i32 4, <4 x i1> <i1 true, i1 true, i1 true, i1 true>, <4 x i32> undef)
+  ret void
+}
+
+define arm_aapcs_vfpcc void @unused2_used(<4 x i32*> %offs) {
+; CHECK-LABEL: unused2_used:
+; CHECK:       @ %bb.0: @ %entry
+; CHECK-NEXT:    bx lr
+entry:
+  %gather1 = call <4 x i32> @llvm.masked.gather.v4i32.v4p0i32(<4 x i32*> %offs, i32 4, <4 x i1> <i1 true, i1 true, i1 true, i1 true>, <4 x i32> undef)
+  %gather2 = call <4 x i32> @llvm.masked.gather.v4i32.v4p0i32(<4 x i32*> %offs, i32 4, <4 x i1> <i1 true, i1 true, i1 true, i1 true>, <4 x i32> undef)
+  %unused = add <4 x i32> %gather1, %gather2
+  ret void
+}
+
+
+declare <4 x i32> @llvm.masked.gather.v4i32.v4p0i32(<4 x i32*>, i32, <4 x i1>, <4 x i32>)
diff --git a/llvm/test/CodeGen/Thumb2/mve-phireg.ll b/llvm/test/CodeGen/Thumb2/mve-phireg.ll
--- a/llvm/test/CodeGen/Thumb2/mve-phireg.ll
+++ b/llvm/test/CodeGen/Thumb2/mve-phireg.ll
@@ -1,5 +1,5 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
-; RUN: llc -O3 -mtriple=thumbv8.1m.main-none-none-eabi -mattr=+mve.fp --arm-memtransfer-tploop=allow -verify-machineinstrs %s -o - | FileCheck %s
+; RUN: llc -O3 -mtriple=thumbv8.1m.main-none-none-eabi -mattr=+mve.fp --arm-memtransfer-tploop=allow -enable-arm-maskedgatscat=false -verify-machineinstrs %s -o - | FileCheck %s
 
 ; verify-machineinstrs previously caught the incorrect use of QPR in the stack reloads.
 
diff --git a/llvm/test/CodeGen/Thumb2/mve-pred-xor.ll b/llvm/test/CodeGen/Thumb2/mve-pred-xor.ll
--- a/llvm/test/CodeGen/Thumb2/mve-pred-xor.ll
+++ b/llvm/test/CodeGen/Thumb2/mve-pred-xor.ll
@@ -170,8 +170,8 @@
 define arm_aapcs_vfpcc <4 x i32> @cmpugez_v4i1(<4 x i32> %a, <4 x i32> %b) {
 ; CHECK-LABEL: cmpugez_v4i1:
 ; CHECK:       @ %bb.0: @ %entry
-; CHECK-NEXT:    vcmp.i32 ne, q0, zr
-; CHECK-NEXT:    vpsel q0, q0, q1
+; CHECK-NEXT:    vcmp.i32 eq, q0, zr
+; CHECK-NEXT:    vpsel q0, q1, q0
 ; CHECK-NEXT:    bx lr
 entry:
   %c1 = icmp eq <4 x i32> %a, zeroinitializer
diff --git a/llvm/test/CodeGen/Thumb2/mve-selectcc.ll b/llvm/test/CodeGen/Thumb2/mve-selectcc.ll
--- a/llvm/test/CodeGen/Thumb2/mve-selectcc.ll
+++ b/llvm/test/CodeGen/Thumb2/mve-selectcc.ll
@@ -1,5 +1,5 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
-; RUN: llc -mtriple=thumbv8.1m.main-none-none-eabi -mattr=+mve.fp -verify-machineinstrs %s -o - | FileCheck %s --check-prefix=CHECK
+; RUN: llc -mtriple=thumbv8.1m.main-none-none-eabi -mattr=+mve.fp -enable-arm-maskedgatscat=false -verify-machineinstrs %s -o - | FileCheck %s --check-prefix=CHECK
 
 define arm_aapcs_vfpcc <4 x i32> @test_v4i32(i32 %x, <4 x i32> %s0, <4 x i32> %s1) {
 ; CHECK-LABEL: test_v4i32:
diff --git a/llvm/test/CodeGen/Thumb2/mve-vqdmulh.ll b/llvm/test/CodeGen/Thumb2/mve-vqdmulh.ll
--- a/llvm/test/CodeGen/Thumb2/mve-vqdmulh.ll
+++ b/llvm/test/CodeGen/Thumb2/mve-vqdmulh.ll
@@ -70,8 +70,6 @@
 define arm_aapcs_vfpcc <8 x i16> @vqdmulh_i16_c(<8 x i16> %s0, <8 x i16> %s1) {
 ; CHECK-LABEL: vqdmulh_i16_c:
 ; CHECK:       @ %bb.0: @ %entry
-; CHECK-NEXT:    .vsave {d8, d9}
-; CHECK-NEXT:    vpush {d8, d9}
 ; CHECK-NEXT:    vmov q2, q0
 ; CHECK-NEXT:    vmov.u16 r0, q0[2]
 ; CHECK-NEXT:    vmov.u16 r1, q0[0]
@@ -86,41 +84,37 @@
 ; CHECK-NEXT:    vmov.u16 r1, q1[1]
 ; CHECK-NEXT:    vmov q3[3], q3[1], r1, r0
 ; CHECK-NEXT:    vmullb.s16 q0, q3, q0
-; CHECK-NEXT:    vmov.i32 q3, #0x7fff
 ; CHECK-NEXT:    vshl.i32 q0, q0, #10
 ; CHECK-NEXT:    vshr.s32 q0, q0, #10
-; CHECK-NEXT:    vshr.s32 q0, q0, #15
-; CHECK-NEXT:    vmin.s32 q4, q0, q3
-; CHECK-NEXT:    vmov r0, r1, d8
+; CHECK-NEXT:    vshr.s32 q3, q0, #15
+; CHECK-NEXT:    vmov r0, r1, d6
 ; CHECK-NEXT:    vmov.16 q0[0], r0
 ; CHECK-NEXT:    vmov.16 q0[1], r1
-; CHECK-NEXT:    vmov r0, r1, d9
+; CHECK-NEXT:    vmov r0, r1, d7
 ; CHECK-NEXT:    vmov.16 q0[2], r0
 ; CHECK-NEXT:    vmov.u16 r0, q2[6]
 ; CHECK-NEXT:    vmov.16 q0[3], r1
 ; CHECK-NEXT:    vmov.u16 r1, q2[4]
-; CHECK-NEXT:    vmov q4[2], q4[0], r1, r0
+; CHECK-NEXT:    vmov q3[2], q3[0], r1, r0
 ; CHECK-NEXT:    vmov.u16 r0, q2[7]
 ; CHECK-NEXT:    vmov.u16 r1, q2[5]
-; CHECK-NEXT:    vmov q4[3], q4[1], r1, r0
+; CHECK-NEXT:    vmov q3[3], q3[1], r1, r0
 ; CHECK-NEXT:    vmov.u16 r0, q1[6]
 ; CHECK-NEXT:    vmov.u16 r1, q1[4]
 ; CHECK-NEXT:    vmov q2[2], q2[0], r1, r0
 ; CHECK-NEXT:    vmov.u16 r0, q1[7]
 ; CHECK-NEXT:    vmov.u16 r1, q1[5]
 ; CHECK-NEXT:    vmov q2[3], q2[1], r1, r0
-; CHECK-NEXT:    vmullb.s16 q1, q2, q4
+; CHECK-NEXT:    vmullb.s16 q1, q2, q3
 ; CHECK-NEXT:    vshl.i32 q1, q1, #10
 ; CHECK-NEXT:    vshr.s32 q1, q1, #10
 ; CHECK-NEXT:    vshr.s32 q1, q1, #15
-; CHECK-NEXT:    vmin.s32 q1, q1, q3
 ; CHECK-NEXT:    vmov r0, r1, d2
 ; CHECK-NEXT:    vmov.16 q0[4], r0
 ; CHECK-NEXT:    vmov.16 q0[5], r1
 ; CHECK-NEXT:    vmov r0, r1, d3
 ; CHECK-NEXT:    vmov.16 q0[6], r0
 ; CHECK-NEXT:    vmov.16 q0[7], r1
-; CHECK-NEXT:    vpop {d8, d9}
 ; CHECK-NEXT:    bx lr
 entry:
   %l2 = sext <8 x i16> %s0 to <8 x i22>