diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
@@ -5712,11 +5712,12 @@
   SDLoc dl(N);
 
   // Check if we can convert between two legal vector types and extract.
-  unsigned InWidenSize = InWidenVT.getSizeInBits();
-  unsigned Size = VT.getSizeInBits();
+  TypeSize InWidenSize = InWidenVT.getSizeInBits();
+  TypeSize Size = VT.getSizeInBits();
   // x86mmx is not an acceptable vector element type, so don't try.
-  if (InWidenSize % Size == 0 && !VT.isVector() && VT != MVT::x86mmx) {
-    unsigned NewNumElts = InWidenSize / Size;
+  if (!VT.isVector() && VT != MVT::x86mmx &&
+      InWidenSize.hasKnownScalarFactor(Size)) {
+    unsigned NewNumElts = InWidenSize.getKnownScalarFactor(Size);
     EVT NewVT = EVT::getVectorVT(*DAG.getContext(), VT, NewNumElts);
     if (TLI.isTypeLegal(NewVT)) {
       SDValue BitOp = DAG.getNode(ISD::BITCAST, dl, NewVT, InOp);
@@ -5731,9 +5732,11 @@
   // having to copy via memory.
   if (VT.isVector()) {
     EVT EltVT = VT.getVectorElementType();
-    unsigned EltSize = EltVT.getSizeInBits();
-    if (InWidenSize % EltSize == 0) {
-      unsigned NewNumElts = InWidenSize / EltSize;
+    unsigned EltSize = EltVT.getFixedSizeInBits();
+    if (InWidenSize.isKnownMultipleOf(EltSize)) {
+      ElementCount NewNumElts =
+          (InWidenVT.getVectorElementCount() * InWidenVT.getScalarSizeInBits())
+              .divideCoefficientBy(EltSize);
       EVT NewVT = EVT::getVectorVT(*DAG.getContext(), EltVT, NewNumElts);
       if (TLI.isTypeLegal(NewVT)) {
         SDValue BitOp = DAG.getNode(ISD::BITCAST, dl, NewVT, InOp);
diff --git a/llvm/test/CodeGen/AArch64/sve-bitcast.ll b/llvm/test/CodeGen/AArch64/sve-bitcast.ll
--- a/llvm/test/CodeGen/AArch64/sve-bitcast.ll
+++ b/llvm/test/CodeGen/AArch64/sve-bitcast.ll
@@ -874,7 +874,14 @@
   ret <vscale x 4 x half> %bc
 }
 
-; @bitcast_nxv1i64_to_nxv4f16 is missing
+define <vscale x 4 x half> @bitcast_nxv1i64_to_nxv4f16(<vscale x 1 x i64> %v) #0 {
+; CHECK-LABEL: bitcast_nxv1i64_to_nxv4f16:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    uunpklo z0.s, z0.h
+; CHECK-NEXT:    ret
+  %bc = bitcast <vscale x 1 x i64> %v to <vscale x 4 x half>
+  ret <vscale x 4 x half> %bc
+}
 
 define <vscale x 4 x half> @bitcast_nxv2f32_to_nxv4f16(<vscale x 2 x float> %v) #0 {
 ; CHECK-LABEL: bitcast_nxv2f32_to_nxv4f16:
@@ -892,7 +899,14 @@
   ret <vscale x 4 x half> %bc
 }
 
-; @bitcast_nxv1f64_to_nxv4f16 is missing
+define <vscale x 4 x half> @bitcast_nxv1f64_to_nxv4f16(<vscale x 1 x double> %v) #0 {
+; CHECK-LABEL: bitcast_nxv1f64_to_nxv4f16:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    uunpklo z0.s, z0.h
+; CHECK-NEXT:    ret
+  %bc = bitcast <vscale x 1 x double> %v to <vscale x 4 x half>
+  ret <vscale x 4 x half> %bc
+}
 
 define <vscale x 4 x half> @bitcast_nxv4bf16_to_nxv4f16(<vscale x 4 x bfloat> %v) #0 {
 ; CHECK-LABEL: bitcast_nxv4bf16_to_nxv4f16:
@@ -946,7 +960,14 @@
   ret <vscale x 2 x float> %bc
 }
 
-; @bitcast_nxv1i64_to_nxv2f32 is missing
+define <vscale x 2 x float> @bitcast_nxv1i64_to_nxv2f32(<vscale x 1 x i64> %v) #0 {
+; CHECK-LABEL: bitcast_nxv1i64_to_nxv2f32:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    uunpklo z0.d, z0.s
+; CHECK-NEXT:    ret
+  %bc = bitcast <vscale x 1 x i64> %v to <vscale x 2 x float>
+  ret <vscale x 2 x float> %bc
+}
 
 define <vscale x 2 x float> @bitcast_nxv4f16_to_nxv2f32(<vscale x 4 x half> %v) #0 {
 ; CHECK-LABEL: bitcast_nxv4f16_to_nxv2f32:
@@ -964,7 +985,14 @@
   ret <vscale x 2 x float> %bc
 }
 
-; @bitcast_nxv1f64_to_nxv2f32 is missing
+define <vscale x 2 x float> @bitcast_nxv1f64_to_nxv2f32(<vscale x 1 x double> %v) #0 {
+; CHECK-LABEL: bitcast_nxv1f64_to_nxv2f32:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    uunpklo z0.d, z0.s
+; CHECK-NEXT:    ret
+  %bc = bitcast <vscale x 1 x double> %v to <vscale x 2 x float>
+  ret <vscale x 2 x float> %bc
+}
 
 define <vscale x 2 x float> @bitcast_nxv4bf16_to_nxv2f32(<vscale x 4 x bfloat> %v) #0 {
 ; CHECK-LABEL: bitcast_nxv4bf16_to_nxv2f32:
@@ -986,13 +1014,67 @@
 ; bitcast to nxv1f64
 ;
 
-; @bitcast_nxv8i8_to_nxv1f64 is missing
-; @bitcast_nxv4i16_to_nxv1f64 is missing
-; @bitcast_nxv2i32_to_nxv1f64 is missing
-; @bitcast_nxv1i64_to_nxv1f64 is missing
-; @bitcast_nxv4f16_to_nxv1f64 is missing
-; @bitcast_nxv2f32_to_nxv1f64 is missing
-; @bitcast_nxv4bf16_to_nxv1f64 is missing
+define <vscale x 1 x double> @bitcast_nxv8i8_to_nxv1f64(<vscale x 8 x i8> %v) #0 {
+; CHECK-LABEL: bitcast_nxv8i8_to_nxv1f64:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    uzp1 z0.b, z0.b, z0.b
+; CHECK-NEXT:    ret
+  %bc = bitcast <vscale x 8 x i8> %v to <vscale x 1 x double>
+  ret <vscale x 1 x double> %bc
+}
+
+define <vscale x 1 x double> @bitcast_nxv4i16_to_nxv1f64(<vscale x 4 x i16> %v) #0 {
+; CHECK-LABEL: bitcast_nxv4i16_to_nxv1f64:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    uzp1 z0.h, z0.h, z0.h
+; CHECK-NEXT:    ret
+  %bc = bitcast <vscale x 4 x i16> %v to <vscale x 1 x double>
+  ret <vscale x 1 x double> %bc
+}
+
+define <vscale x 1 x double> @bitcast_nxv2i32_to_nxv1f64(<vscale x 2 x i32> %v) #0 {
+; CHECK-LABEL: bitcast_nxv2i32_to_nxv1f64:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    uzp1 z0.s, z0.s, z0.s
+; CHECK-NEXT:    ret
+  %bc = bitcast <vscale x 2 x i32> %v to <vscale x 1 x double>
+  ret <vscale x 1 x double> %bc
+}
+
+define <vscale x 1 x double> @bitcast_nxv1i64_to_nxv1f64(<vscale x 1 x i64> %v) #0 {
+; CHECK-LABEL: bitcast_nxv1i64_to_nxv1f64:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    ret
+  %bc = bitcast <vscale x 1 x i64> %v to <vscale x 1 x double>
+  ret <vscale x 1 x double> %bc
+}
+
+define <vscale x 1 x double> @bitcast_nxv4f16_to_nxv1f64(<vscale x 4 x half> %v) #0 {
+; CHECK-LABEL: bitcast_nxv4f16_to_nxv1f64:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    uzp1 z0.h, z0.h, z0.h
+; CHECK-NEXT:    ret
+  %bc = bitcast <vscale x 4 x half> %v to <vscale x 1 x double>
+  ret <vscale x 1 x double> %bc
+}
+
+define <vscale x 1 x double> @bitcast_nxv2f32_to_nxv1f64(<vscale x 2 x float> %v) #0 {
+; CHECK-LABEL: bitcast_nxv2f32_to_nxv1f64:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    uzp1 z0.s, z0.s, z0.s
+; CHECK-NEXT:    ret
+  %bc = bitcast <vscale x 2 x float> %v to <vscale x 1 x double>
+  ret <vscale x 1 x double> %bc
+}
+
+define <vscale x 1 x double> @bitcast_nxv4bf16_to_nxv1f64(<vscale x 4 x bfloat> %v) #0 {
+; CHECK-LABEL: bitcast_nxv4bf16_to_nxv1f64:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    uzp1 z0.h, z0.h, z0.h
+; CHECK-NEXT:    ret
+  %bc = bitcast <vscale x 4 x bfloat> %v to <vscale x 1 x double>
+  ret <vscale x 1 x double> %bc
+}
 
 ;
 ; bitcast to nxv4bf16
@@ -1038,7 +1120,14 @@
   ret <vscale x 4 x bfloat> %bc
 }
 
-; @bitcast_nxv1i64_to_nxv4bf16 is missing
+define <vscale x 4 x bfloat> @bitcast_nxv1i64_to_nxv4bf16(<vscale x 1 x i64> %v) #0 {
+; CHECK-LABEL: bitcast_nxv1i64_to_nxv4bf16:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    uunpklo z0.s, z0.h
+; CHECK-NEXT:    ret
+  %bc = bitcast <vscale x 1 x i64> %v to <vscale x 4 x bfloat>
+  ret <vscale x 4 x bfloat> %bc
+}
 
 define <vscale x 4 x bfloat> @bitcast_nxv4f16_to_nxv4bf16(<vscale x 4 x half> %v) #0 {
 ; CHECK-LABEL: bitcast_nxv4f16_to_nxv4bf16:
@@ -1064,7 +1153,14 @@
   ret <vscale x 4 x bfloat> %bc
 }
 
-; @bitcast_nxv1f64_to_nxv4bf16 is missing
+define <vscale x 4 x bfloat> @bitcast_nxv1f64_to_nxv4bf16(<vscale x 1 x double> %v) #0 {
+; CHECK-LABEL: bitcast_nxv1f64_to_nxv4bf16:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    uunpklo z0.s, z0.h
+; CHECK-NEXT:    ret
+  %bc = bitcast <vscale x 1 x double> %v to <vscale x 4 x bfloat>
+  ret <vscale x 4 x bfloat> %bc
+}
 
 ;
 ; bitcast to nxv4i8
@@ -1275,6 +1371,16 @@
   ret <vscale x 2 x half> %bc
 }
 
+;
+; bitcast to nxv1f32
+;
+
+; @bitcast_nxv4i8_to_nxv1f32 is missing
+; @bitcast_nxv2i16_to_nxv1f32 is missing
+; @bitcast_nxv1i32_to_nxv1f32 is missing
+; @bitcast_nxv2f16_to_nxv1f32 is missing
+; @bitcast_nxv2bf16_to_nxv1f32 is missing
+
 ;
 ; bitcast to nxv2bf16
 ;
@@ -1351,6 +1457,22 @@
 ; @bitcast_nxv1f16_to_nxv1i16 is missing
 ; @bitcast_nxv1bf16_to_nxv1i16 is missing
 
+;
+; bitcast to nxv1f16
+;
+
+; @bitcast_nxv2i8_to_nxv1f16 is missing
+; @bitcast_nxv1i16_to_nxv1f16 is missing
+; @bitcast_nxv1bf16_to_nxv1f16 is missing
+
+;
+; bitcast to nxv1bf16
+;
+
+; @bitcast_nxv2i8_to_nxv1bf16 is missing
+; @bitcast_nxv1i16_to_nxv1bf16 is missing
+; @bitcast_nxv1f16_to_nxv1bf16 is missing
+
 ;
 ; Other
 ;