diff --git a/llvm/lib/Target/SystemZ/SystemZInstrFormats.td b/llvm/lib/Target/SystemZ/SystemZInstrFormats.td
--- a/llvm/lib/Target/SystemZ/SystemZInstrFormats.td
+++ b/llvm/lib/Target/SystemZ/SystemZInstrFormats.td
@@ -4822,7 +4822,7 @@
                        RegisterOperand cls2>
   : InstRIEf<opcode, (outs cls1:$R1),
              (ins cls1:$R1src, cls2:$R2, imm32zx8:$I3, imm32zx8:$I4,
-                  imm32zx6:$I5),
+                  imm32zx8:$I5),
              mnemonic#"\t$R1, $R2, $I3, $I4, $I5", []> {
   let Constraints = "$R1 = $R1src";
   let DisableEncoding = "$R1src";
@@ -5107,7 +5107,7 @@
 class RotateSelectRIEfPseudo<RegisterOperand cls1, RegisterOperand cls2>
   : Pseudo<(outs cls1:$R1),
            (ins cls1:$R1src, cls2:$R2, imm32zx8:$I3, imm32zx8:$I4,
-                imm32zx6:$I5),
+                imm32zx8:$I5),
            []> {
   let Constraints = "$R1 = $R1src";
   let DisableEncoding = "$R1src";
@@ -5252,7 +5252,7 @@
 class RotateSelectAliasRIEf<RegisterOperand cls1, RegisterOperand cls2>
   : Alias<6, (outs cls1:$R1),
           (ins cls1:$R1src, cls2:$R2, imm32zx8:$I3, imm32zx8:$I4,
-               imm32zx6:$I5), []> {
+               imm32zx8:$I5), []> {
   let Constraints = "$R1 = $R1src";
 }
 
diff --git a/llvm/lib/Target/SystemZ/SystemZOperands.td b/llvm/lib/Target/SystemZ/SystemZOperands.td
--- a/llvm/lib/Target/SystemZ/SystemZOperands.td
+++ b/llvm/lib/Target/SystemZ/SystemZOperands.td
@@ -357,10 +357,6 @@
   return isUInt<4>(N->getZExtValue());
 }], UIMM8EVEN, "U4Imm">;
 
-defm imm32zx6 : Immediate<i32, [{
-  return isUInt<6>(N->getZExtValue());
-}], NOOP_SDNodeXForm, "U6Imm">;
-
 defm imm32sx8 : Immediate<i32, [{
   return isInt<8>(N->getSExtValue());
 }], SIMM8, "S8Imm">;
diff --git a/llvm/test/MC/SystemZ/insn-bad-z196.s b/llvm/test/MC/SystemZ/insn-bad-z196.s
--- a/llvm/test/MC/SystemZ/insn-bad-z196.s
+++ b/llvm/test/MC/SystemZ/insn-bad-z196.s
@@ -1208,10 +1208,6 @@
 
 	risbgn	%r1, %r2, 0, 0, 0
 
-#CHECK: error: invalid operand
-#CHECK: risbhg	%r0,%r0,0,0,-1
-#CHECK: error: invalid operand
-#CHECK: risbhg	%r0,%r0,0,0,64
 #CHECK: error: invalid operand
 #CHECK: risbhg	%r0,%r0,0,-1,0
 #CHECK: error: invalid operand
@@ -1221,17 +1217,11 @@
 #CHECK: error: invalid operand
 #CHECK: risbhg	%r0,%r0,256,0,0
 
-	risbhg	%r0,%r0,0,0,-1
-	risbhg	%r0,%r0,0,0,64
 	risbhg	%r0,%r0,0,-1,0
 	risbhg	%r0,%r0,0,256,0
 	risbhg	%r0,%r0,-1,0,0
 	risbhg	%r0,%r0,256,0,0
 
-#CHECK: error: invalid operand
-#CHECK: risblg	%r0,%r0,0,0,-1
-#CHECK: error: invalid operand
-#CHECK: risblg	%r0,%r0,0,0,64
 #CHECK: error: invalid operand
 #CHECK: risblg	%r0,%r0,0,-1,0
 #CHECK: error: invalid operand
@@ -1241,8 +1231,6 @@
 #CHECK: error: invalid operand
 #CHECK: risblg	%r0,%r0,256,0,0
 
-	risblg	%r0,%r0,0,0,-1
-	risblg	%r0,%r0,0,0,64
 	risblg	%r0,%r0,0,-1,0
 	risblg	%r0,%r0,0,256,0
 	risblg	%r0,%r0,-1,0,0
diff --git a/llvm/test/MC/SystemZ/insn-bad-zEC12.s b/llvm/test/MC/SystemZ/insn-bad-zEC12.s
--- a/llvm/test/MC/SystemZ/insn-bad-zEC12.s
+++ b/llvm/test/MC/SystemZ/insn-bad-zEC12.s
@@ -370,10 +370,6 @@
 
 	ppno	%r2, %r4
 
-#CHECK: error: invalid operand
-#CHECK: risbgn	%r0,%r0,0,0,-1
-#CHECK: error: invalid operand
-#CHECK: risbgn	%r0,%r0,0,0,64
 #CHECK: error: invalid operand
 #CHECK: risbgn	%r0,%r0,0,-1,0
 #CHECK: error: invalid operand
@@ -383,8 +379,6 @@
 #CHECK: error: invalid operand
 #CHECK: risbgn	%r0,%r0,256,0,0
 
-	risbgn	%r0,%r0,0,0,-1
-	risbgn	%r0,%r0,0,0,64
 	risbgn	%r0,%r0,0,-1,0
 	risbgn	%r0,%r0,0,256,0
 	risbgn	%r0,%r0,-1,0,0
diff --git a/llvm/test/MC/SystemZ/insn-bad.s b/llvm/test/MC/SystemZ/insn-bad.s
--- a/llvm/test/MC/SystemZ/insn-bad.s
+++ b/llvm/test/MC/SystemZ/insn-bad.s
@@ -5635,8 +5635,6 @@
 #CHECK: error: invalid operand
 #CHECK: risbg	%r0,%r0,0,0,-1
 #CHECK: error: invalid operand
-#CHECK: risbg	%r0,%r0,0,0,64
-#CHECK: error: invalid operand
 #CHECK: risbg	%r0,%r0,0,-1,0
 #CHECK: error: invalid operand
 #CHECK: risbg	%r0,%r0,0,256,0
@@ -5646,7 +5644,6 @@
 #CHECK: risbg	%r0,%r0,256,0,0
 
 	risbg	%r0,%r0,0,0,-1
-	risbg	%r0,%r0,0,0,64
 	risbg	%r0,%r0,0,-1,0
 	risbg	%r0,%r0,0,256,0
 	risbg	%r0,%r0,-1,0,0
@@ -5684,10 +5681,6 @@
 	rllg	%r0,%r0,524288
 	rllg	%r0,%r0,0(%r1,%r2)
 
-#CHECK: error: invalid operand
-#CHECK: rnsbg	%r0,%r0,0,0,-1
-#CHECK: error: invalid operand
-#CHECK: rnsbg	%r0,%r0,0,0,64
 #CHECK: error: invalid operand
 #CHECK: rnsbg	%r0,%r0,0,-1,0
 #CHECK: error: invalid operand
@@ -5697,17 +5690,11 @@
 #CHECK: error: invalid operand
 #CHECK: rnsbg	%r0,%r0,256,0,0
 
-	rnsbg	%r0,%r0,0,0,-1
-	rnsbg	%r0,%r0,0,0,64
 	rnsbg	%r0,%r0,0,-1,0
 	rnsbg	%r0,%r0,0,256,0
 	rnsbg	%r0,%r0,-1,0,0
 	rnsbg	%r0,%r0,256,0,0
 
-#CHECK: error: invalid operand
-#CHECK: rosbg	%r0,%r0,0,0,-1
-#CHECK: error: invalid operand
-#CHECK: rosbg	%r0,%r0,0,0,64
 #CHECK: error: invalid operand
 #CHECK: rosbg	%r0,%r0,0,-1,0
 #CHECK: error: invalid operand
@@ -5717,8 +5704,6 @@
 #CHECK: error: invalid operand
 #CHECK: rosbg	%r0,%r0,256,0,0
 
-	rosbg	%r0,%r0,0,0,-1
-	rosbg	%r0,%r0,0,0,64
 	rosbg	%r0,%r0,0,-1,0
 	rosbg	%r0,%r0,0,256,0
 	rosbg	%r0,%r0,-1,0,0
@@ -5765,10 +5750,6 @@
 	rrxtr	%f0, %f2, %f0, 0
 	rrxtr	%f2, %f0, %f0, 0
 
-#CHECK: error: invalid operand
-#CHECK: rxsbg	%r0,%r0,0,0,-1
-#CHECK: error: invalid operand
-#CHECK: rxsbg	%r0,%r0,0,0,64
 #CHECK: error: invalid operand
 #CHECK: rxsbg	%r0,%r0,0,-1,0
 #CHECK: error: invalid operand
@@ -5778,8 +5759,6 @@
 #CHECK: error: invalid operand
 #CHECK: rxsbg	%r0,%r0,256,0,0
 
-	rxsbg	%r0,%r0,0,0,-1
-	rxsbg	%r0,%r0,0,0,64
 	rxsbg	%r0,%r0,0,-1,0
 	rxsbg	%r0,%r0,0,256,0
 	rxsbg	%r0,%r0,-1,0,0
diff --git a/llvm/test/MC/SystemZ/insn-good-z196.s b/llvm/test/MC/SystemZ/insn-good-z196.s
--- a/llvm/test/MC/SystemZ/insn-good-z196.s
+++ b/llvm/test/MC/SystemZ/insn-good-z196.s
@@ -1777,6 +1777,8 @@
 
 #CHECK: risbhg	%r0, %r0, 0, 0, 0       # encoding: [0xec,0x00,0x00,0x00,0x00,0x5d]
 #CHECK: risbhg	%r0, %r0, 0, 0, 63      # encoding: [0xec,0x00,0x00,0x00,0x3f,0x5d]
+#CHECK: risbhg	%r0, %r0, 0, 0, 64      # encoding: [0xec,0x00,0x00,0x00,0x40,0x5d]
+#CHECK: risbhg	%r0, %r0, 0, 0, 255     # encoding: [0xec,0x00,0x00,0x00,0xff,0x5d]
 #CHECK: risbhg	%r0, %r0, 0, 255, 0     # encoding: [0xec,0x00,0x00,0xff,0x00,0x5d]
 #CHECK: risbhg	%r0, %r0, 255, 0, 0     # encoding: [0xec,0x00,0xff,0x00,0x00,0x5d]
 #CHECK: risbhg	%r0, %r15, 0, 0, 0      # encoding: [0xec,0x0f,0x00,0x00,0x00,0x5d]
@@ -1785,6 +1787,8 @@
 
 	risbhg	%r0,%r0,0,0,0
 	risbhg	%r0,%r0,0,0,63
+	risbhg	%r0,%r0,0,0,64
+	risbhg	%r0,%r0,0,0,255
 	risbhg	%r0,%r0,0,255,0
 	risbhg	%r0,%r0,255,0,0
 	risbhg	%r0,%r15,0,0,0
@@ -1793,6 +1797,8 @@
 
 #CHECK: risblg	%r0, %r0, 0, 0, 0       # encoding: [0xec,0x00,0x00,0x00,0x00,0x51]
 #CHECK: risblg	%r0, %r0, 0, 0, 63      # encoding: [0xec,0x00,0x00,0x00,0x3f,0x51]
+#CHECK: risblg	%r0, %r0, 0, 0, 64      # encoding: [0xec,0x00,0x00,0x00,0x40,0x51]
+#CHECK: risblg	%r0, %r0, 0, 0, 255     # encoding: [0xec,0x00,0x00,0x00,0xff,0x51]
 #CHECK: risblg	%r0, %r0, 0, 255, 0     # encoding: [0xec,0x00,0x00,0xff,0x00,0x51]
 #CHECK: risblg	%r0, %r0, 255, 0, 0     # encoding: [0xec,0x00,0xff,0x00,0x00,0x51]
 #CHECK: risblg	%r0, %r15, 0, 0, 0      # encoding: [0xec,0x0f,0x00,0x00,0x00,0x51]
@@ -1801,6 +1807,8 @@
 
 	risblg	%r0,%r0,0,0,0
 	risblg	%r0,%r0,0,0,63
+	risblg	%r0,%r0,0,0,64
+	risblg	%r0,%r0,0,0,255
 	risblg	%r0,%r0,0,255,0
 	risblg	%r0,%r0,255,0,0
 	risblg	%r0,%r15,0,0,0
diff --git a/llvm/test/MC/SystemZ/insn-good-zEC12.s b/llvm/test/MC/SystemZ/insn-good-zEC12.s
--- a/llvm/test/MC/SystemZ/insn-good-zEC12.s
+++ b/llvm/test/MC/SystemZ/insn-good-zEC12.s
@@ -436,6 +436,8 @@
 
 #CHECK: risbgn	%r0, %r0, 0, 0, 0       # encoding: [0xec,0x00,0x00,0x00,0x00,0x59]
 #CHECK: risbgn	%r0, %r0, 0, 0, 63      # encoding: [0xec,0x00,0x00,0x00,0x3f,0x59]
+#CHECK: risbgn	%r0, %r0, 0, 0, 64      # encoding: [0xec,0x00,0x00,0x00,0x40,0x59]
+#CHECK: risbgn	%r0, %r0, 0, 0, 255     # encoding: [0xec,0x00,0x00,0x00,0xff,0x59]
 #CHECK: risbgn	%r0, %r0, 0, 255, 0     # encoding: [0xec,0x00,0x00,0xff,0x00,0x59]
 #CHECK: risbgn	%r0, %r0, 255, 0, 0     # encoding: [0xec,0x00,0xff,0x00,0x00,0x59]
 #CHECK: risbgn	%r0, %r15, 0, 0, 0      # encoding: [0xec,0x0f,0x00,0x00,0x00,0x59]
@@ -444,6 +446,8 @@
 
 	risbgn	%r0,%r0,0,0,0
 	risbgn	%r0,%r0,0,0,63
+	risbgn	%r0,%r0,0,0,64
+	risbgn	%r0,%r0,0,0,255
 	risbgn	%r0,%r0,0,255,0
 	risbgn	%r0,%r0,255,0,0
 	risbgn	%r0,%r15,0,0,0
diff --git a/llvm/test/MC/SystemZ/insn-good.s b/llvm/test/MC/SystemZ/insn-good.s
--- a/llvm/test/MC/SystemZ/insn-good.s
+++ b/llvm/test/MC/SystemZ/insn-good.s
@@ -13467,6 +13467,8 @@
 
 #CHECK: risbg	%r0, %r0, 0, 0, 0       # encoding: [0xec,0x00,0x00,0x00,0x00,0x55]
 #CHECK: risbg	%r0, %r0, 0, 0, 63      # encoding: [0xec,0x00,0x00,0x00,0x3f,0x55]
+#CHECK: risbg	%r0, %r0, 0, 0, 64      # encoding: [0xec,0x00,0x00,0x00,0x40,0x55]
+#CHECK: risbg	%r0, %r0, 0, 0, 255     # encoding: [0xec,0x00,0x00,0x00,0xff,0x55]
 #CHECK: risbg	%r0, %r0, 0, 255, 0     # encoding: [0xec,0x00,0x00,0xff,0x00,0x55]
 #CHECK: risbg	%r0, %r0, 255, 0, 0     # encoding: [0xec,0x00,0xff,0x00,0x00,0x55]
 #CHECK: risbg	%r0, %r15, 0, 0, 0      # encoding: [0xec,0x0f,0x00,0x00,0x00,0x55]
@@ -13475,6 +13477,8 @@
 
 	risbg	%r0,%r0,0,0,0
 	risbg	%r0,%r0,0,0,63
+	risbg	%r0,%r0,0,0,64
+	risbg	%r0,%r0,0,0,255
 	risbg	%r0,%r0,0,255,0
 	risbg	%r0,%r0,255,0,0
 	risbg	%r0,%r15,0,0,0
@@ -13535,6 +13539,8 @@
 
 #CHECK: rnsbg	%r0, %r0, 0, 0, 0       # encoding: [0xec,0x00,0x00,0x00,0x00,0x54]
 #CHECK: rnsbg	%r0, %r0, 0, 0, 63      # encoding: [0xec,0x00,0x00,0x00,0x3f,0x54]
+#CHECK: rnsbg	%r0, %r0, 0, 0, 64      # encoding: [0xec,0x00,0x00,0x00,0x40,0x54]
+#CHECK: rnsbg	%r0, %r0, 0, 0, 255     # encoding: [0xec,0x00,0x00,0x00,0xff,0x54]
 #CHECK: rnsbg	%r0, %r0, 0, 255, 0     # encoding: [0xec,0x00,0x00,0xff,0x00,0x54]
 #CHECK: rnsbg	%r0, %r0, 255, 0, 0     # encoding: [0xec,0x00,0xff,0x00,0x00,0x54]
 #CHECK: rnsbg	%r0, %r15, 0, 0, 0      # encoding: [0xec,0x0f,0x00,0x00,0x00,0x54]
@@ -13543,6 +13549,8 @@
 
 	rnsbg	%r0,%r0,0,0,0
 	rnsbg	%r0,%r0,0,0,63
+	rnsbg	%r0,%r0,0,0,64
+	rnsbg	%r0,%r0,0,0,255
 	rnsbg	%r0,%r0,0,255,0
 	rnsbg	%r0,%r0,255,0,0
 	rnsbg	%r0,%r15,0,0,0
@@ -13551,6 +13559,8 @@
 
 #CHECK: rosbg	%r0, %r0, 0, 0, 0       # encoding: [0xec,0x00,0x00,0x00,0x00,0x56]
 #CHECK: rosbg	%r0, %r0, 0, 0, 63      # encoding: [0xec,0x00,0x00,0x00,0x3f,0x56]
+#CHECK: rosbg	%r0, %r0, 0, 0, 64      # encoding: [0xec,0x00,0x00,0x00,0x40,0x56]
+#CHECK: rosbg	%r0, %r0, 0, 0, 255     # encoding: [0xec,0x00,0x00,0x00,0xff,0x56]
 #CHECK: rosbg	%r0, %r0, 0, 255, 0     # encoding: [0xec,0x00,0x00,0xff,0x00,0x56]
 #CHECK: rosbg	%r0, %r0, 255, 0, 0     # encoding: [0xec,0x00,0xff,0x00,0x00,0x56]
 #CHECK: rosbg	%r0, %r15, 0, 0, 0      # encoding: [0xec,0x0f,0x00,0x00,0x00,0x56]
@@ -13559,6 +13569,8 @@
 
 	rosbg	%r0,%r0,0,0,0
 	rosbg	%r0,%r0,0,0,63
+	rosbg	%r0,%r0,0,0,64
+	rosbg	%r0,%r0,0,0,255
 	rosbg	%r0,%r0,0,255,0
 	rosbg	%r0,%r0,255,0,0
 	rosbg	%r0,%r15,0,0,0
@@ -13625,6 +13637,8 @@
 
 #CHECK: rxsbg	%r0, %r0, 0, 0, 0       # encoding: [0xec,0x00,0x00,0x00,0x00,0x57]
 #CHECK: rxsbg	%r0, %r0, 0, 0, 63      # encoding: [0xec,0x00,0x00,0x00,0x3f,0x57]
+#CHECK: rxsbg	%r0, %r0, 0, 0, 64      # encoding: [0xec,0x00,0x00,0x00,0x40,0x57]
+#CHECK: rxsbg	%r0, %r0, 0, 0, 255     # encoding: [0xec,0x00,0x00,0x00,0xff,0x57]
 #CHECK: rxsbg	%r0, %r0, 0, 255, 0     # encoding: [0xec,0x00,0x00,0xff,0x00,0x57]
 #CHECK: rxsbg	%r0, %r0, 255, 0, 0     # encoding: [0xec,0x00,0xff,0x00,0x00,0x57]
 #CHECK: rxsbg	%r0, %r15, 0, 0, 0      # encoding: [0xec,0x0f,0x00,0x00,0x00,0x57]
@@ -13633,6 +13647,8 @@
 
 	rxsbg	%r0,%r0,0,0,0
 	rxsbg	%r0,%r0,0,0,63
+	rxsbg	%r0,%r0,0,0,64
+	rxsbg	%r0,%r0,0,0,255
 	rxsbg	%r0,%r0,0,255,0
 	rxsbg	%r0,%r0,255,0,0
 	rxsbg	%r0,%r15,0,0,0