Add support for monitorx/mwaitx instructions

gas/

	* config/tc-i386.c (cpu_arch): Add .mwaitx.
	(process_immext): Check operands for monitorx/mwaitx instructions.
	* doc/c-i386.texi: Document mwaitx.

gas/testsuite/

	* gas/i386/i386.exp: Add new mwaitx test cases.
	* gas/i386/mwaitx.s: New.
	* gas/i386/mwaitx-bdver4.d: New.
	* gas/i386/x86-64-mwaitx.s: New.
	* gas/i386/x86-64-mwaitx-bdver4.d: New.
	* gas/i386/mwaitx-reg.s: New.
	* gas/i386/mwaitx-reg.l: New.
	* gas/i386/x86-64-mwaitx-reg.l: New.
	* gas/i386/x86-64-mwaitx-reg.s: New.
	* gas/i386/arch-13.s: Updated.
	* gas/i386/arch-13.d: Updated.
	* gas/i386/arch-13-znver1.d: Updated.
	* gas/i386/x86-64-arch-3.s: Updated.
	* gas/i386/x86-64-arch-3.d: Updated.
	* gas/i386/x86-64-arch-3-znver1.d: Updated.

opcodes/

	* i386-dis.c (OP_Mwaitx): New.
	(rm_table): Add monitorx/mwaitx.
	* i386-gen.c (cpu_flag_init): Add CpuMWAITX to CPU_BDVER4_FLAGS
	and CPU_ZNVER1_FLAGS.  Add CPU_MWAITX_FLAGS.
	(operand_type_init): Add CpuMWAITX.
	* i386-opc.h (CpuMWAITX): New.
	(i386_cpu_flags): Add cpumwaitx.
	* i386-opc.tbl: Add monitorx and mwaitx.
	* i386-init.h: Regenerated.
	* i386-tbl.h: Likewise.

19 files changed, 342 insertions, 5 deletions

diff --git a/gas/ChangeLog b/gas/ChangeLog
index 7c49ea6b18f..77965773c52 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,9 @@
+2015-06-30  Amit Pawar  <Amit.Pawar@amd.com>
+
+	* config/tc-i386.c (cpu_arch): Add .mwaitx.
+	(process_immext): Check operands for monitorx/mwaitx instructions.
+	* doc/c-i386.texi: Document mwaitx.
+
 2015-06-28  H.J. Lu  <hongjiu.lu@intel.com>
 
 	* as.c (parse_args): Replace COMPRESS_DEBUG_ZLIB with
diff --git a/gas/config/tc-i386.c b/gas/config/tc-i386.c
index d8405b5d8ee..5a1e2b3944a 100644
--- a/gas/config/tc-i386.c
+++ b/gas/config/tc-i386.c
@@ -954,6 +954,8 @@ static const arch_entry cpu_arch[] =
     CPU_AVX512VBMI_FLAGS, 0, 0 },
   { STRING_COMMA_LEN (".clzero"), PROCESSOR_UNKNOWN,
     CPU_CLZERO_FLAGS, 0, 0 },
+  { STRING_COMMA_LEN (".mwaitx"), PROCESSOR_UNKNOWN,
+    CPU_MWAITX_FLAGS, 0, 0 },
 };
 
 #ifdef I386COFF
@@ -3347,6 +3349,34 @@ process_immext (void)
       i.operands = 0;
     }
 
+  if (i.tm.cpu_flags.bitfield.cpumwaitx && i.operands > 0)
+    {
+      /* MONITORX/MWAITX instructions have fixed operands with an opcode
+	 suffix which is coded in the same place as an 8-bit immediate
+	 field would be.
+	 Here we check those operands and remove them afterwards.  */
+      unsigned int x;
+
+      if (i.operands != 3)
+	abort();
+
+      for (x = 0; x < 2; x++)
+	if (register_number (i.op[x].regs) != x)
+	  goto bad_register_operand;
+
+      /* Check for third operand for mwaitx/monitorx insn.  */
+      if (register_number (i.op[x].regs)
+	  != (x + (i.tm.extension_opcode == 0xfb)))
+	{
+bad_register_operand:
+	  as_bad (_("can't use register '%s%s' as operand %d in '%s'."),
+		  register_prefix, i.op[x].regs->reg_name, x+1,
+		  i.tm.name);
+	}
+
+      i.operands = 0;
+    }
+
   /* These AMD 3DNow! and SSE2 instructions have an opcode suffix
      which is coded in the same place as an 8-bit immediate field
      would be.  Here we fake an 8-bit immediate operand from the
diff --git a/gas/doc/c-i386.texi b/gas/doc/c-i386.texi
index 61189876f73..4af05e30b6f 100644
--- a/gas/doc/c-i386.texi
+++ b/gas/doc/c-i386.texi
@@ -189,6 +189,7 @@ accept various extension mnemonics.  For example,
 @code{rtm},
 @code{invpcid},
 @code{clflush},
+@code{mwaitx},
 @code{clzero},
 @code{lwp},
 @code{fma4},
@@ -1112,7 +1113,7 @@ supported on the CPU specified.  The choices for @var{cpu_type} are:
 @item @samp{.3dnow} @tab @samp{.3dnowa} @tab @samp{.sse4a} @tab @samp{.sse5}
 @item @samp{.syscall} @tab @samp{.rdtscp} @tab @samp{.svme} @tab @samp{.abm}
 @item @samp{.lwp} @tab @samp{.fma4} @tab @samp{.xop} @tab @samp{.cx16}
-@item @samp{.padlock} @tab @samp{.clzero}
+@item @samp{.padlock} @tab @samp{.clzero} @tab @samp{.mwaitx}
 @end multitable
 
 Apart from the warning, there are only two other effects on
diff --git a/gas/testsuite/ChangeLog b/gas/testsuite/ChangeLog
index e7ab1cf5eca..3d4848b6c78 100644
--- a/gas/testsuite/ChangeLog
+++ b/gas/testsuite/ChangeLog
@@ -1,3 +1,21 @@
+2015-06-30  Amit Pawar  <Amit.Pawar@amd.com>
+
+	* gas/i386/i386.exp: Add new mwaitx test cases.
+	* gas/i386/mwaitx.s: New.
+	* gas/i386/mwaitx-bdver4.d: New.
+	* gas/i386/x86-64-mwaitx.s: New.
+	* gas/i386/x86-64-mwaitx-bdver4.d: New.
+	* gas/i386/mwaitx-reg.s: New.
+	* gas/i386/mwaitx-reg.l: New.
+	* gas/i386/x86-64-mwaitx-reg.l: New.
+	* gas/i386/x86-64-mwaitx-reg.s: New.
+	* gas/i386/arch-13.s: Updated.
+	* gas/i386/arch-13.d: Updated.
+	* gas/i386/arch-13-znver1.d: Updated.
+	* gas/i386/x86-64-arch-3.s: Updated.
+	* gas/i386/x86-64-arch-3.d: Updated.
+	* gas/i386/x86-64-arch-3-znver1.d: Updated.
+
 2015-06-27  H.J. Lu  <hongjiu.lu@intel.com>
 
 	* gas/ia64/psn.d: Updated.
diff --git a/gas/testsuite/gas/i386/arch-13-znver1.d b/gas/testsuite/gas/i386/arch-13-znver1.d
index bafe606ec46..b76cfabb420 100644
--- a/gas/testsuite/gas/i386/arch-13-znver1.d
+++ b/gas/testsuite/gas/i386/arch-13-znver1.d
@@ -17,4 +17,9 @@ Disassembly of section .text:
 [ 	]*[a-f0-9]+:	0f c7 21             	xsavec \(%ecx\)
 [ 	]*[a-f0-9]+:	0f c7 29             	xsaves \(%ecx\)
 [ 	]*[a-f0-9]+:	66 0f ae 39          	clflushopt \(%ecx\)
+[ 	]*[a-f0-9]+:	0f 01 fa             	monitorx %eax,%ecx,%edx
+[ 	]*[a-f0-9]+:	67 0f 01 fa          	monitorx %ax,%ecx,%edx
+[ 	]*[a-f0-9]+:	0f 01 fa             	monitorx %eax,%ecx,%edx
+[ 	]*[a-f0-9]+:	0f 01 fb             	mwaitx %eax,%ecx,%ebx
+[ 	]*[a-f0-9]+:	0f 01 fb             	mwaitx %eax,%ecx,%ebx
 #pass
diff --git a/gas/testsuite/gas/i386/arch-13.d b/gas/testsuite/gas/i386/arch-13.d
index 370e6417da7..6296ab74d55 100644
--- a/gas/testsuite/gas/i386/arch-13.d
+++ b/gas/testsuite/gas/i386/arch-13.d
@@ -1,4 +1,4 @@
-#as: -march=i686+smap+adx+rdseed+clzero+xsavec+xsaves+clflushopt
+#as: -march=i686+smap+adx+rdseed+clzero+xsavec+xsaves+clflushopt+mwaitx
 #objdump: -dw
 #name: i386 arch 13
 
@@ -16,4 +16,9 @@ Disassembly of section .text:
 [ 	]*[a-f0-9]+:	0f c7 21             	xsavec \(%ecx\)
 [ 	]*[a-f0-9]+:	0f c7 29             	xsaves \(%ecx\)
 [ 	]*[a-f0-9]+:	66 0f ae 39          	clflushopt \(%ecx\)
+[ 	]*[a-f0-9]+:	0f 01 fa             	monitorx %eax,%ecx,%edx
+[ 	]*[a-f0-9]+:	67 0f 01 fa          	monitorx %ax,%ecx,%edx
+[ 	]*[a-f0-9]+:	0f 01 fa             	monitorx %eax,%ecx,%edx
+[ 	]*[a-f0-9]+:	0f 01 fb             	mwaitx %eax,%ecx,%ebx
+[ 	]*[a-f0-9]+:	0f 01 fb             	mwaitx %eax,%ecx,%ebx
 #pass
diff --git a/gas/testsuite/gas/i386/arch-13.s b/gas/testsuite/gas/i386/arch-13.s
index 5e1969f4f7e..4e82ff6e433 100644
--- a/gas/testsuite/gas/i386/arch-13.s
+++ b/gas/testsuite/gas/i386/arch-13.s
@@ -16,4 +16,8 @@ xsavec  (%ecx)
 xsaves  (%ecx)
 #CLFLUSHOPT
 clflushopt      (%ecx)
-
+monitorx %eax, %ecx, %edx
+monitorx %ax, %ecx, %edx
+monitorx
+mwaitx %eax, %ecx, %ebx
+mwaitx
diff --git a/gas/testsuite/gas/i386/i386.exp b/gas/testsuite/gas/i386/i386.exp
index 9ff38d34d25..d36d5c64e05 100644
--- a/gas/testsuite/gas/i386/i386.exp
+++ b/gas/testsuite/gas/i386/i386.exp
@@ -340,6 +340,8 @@ if [expr ([istarget "i*86-*-*"] ||  [istarget "x86_64-*-*"]) && [gas_32_check]]
     run_dump_test "avx512vbmi_vl-intel"
     run_dump_test "clzero"
     run_dump_test "disassem"
+    run_dump_test "mwaitx-bdver4"
+    run_list_test "mwaitx-reg"
 
     # These tests require support for 8 and 16 bit relocs,
     # so we only run them for ELF and COFF targets.
@@ -721,6 +723,8 @@ if [expr ([istarget "i*86-*-*"] || [istarget "x86_64-*-*"]) && [gas_64_check]] t
     run_dump_test "x86-64-avx512vbmi_vl"
     run_dump_test "x86-64-avx512vbmi_vl-intel"
     run_dump_test "x86-64-clzero"
+    run_dump_test "x86-64-mwaitx-bdver4"
+    run_list_test "x86-64-mwaitx-reg"
 
     if { ![istarget "*-*-aix*"]
       && ![istarget "*-*-beos*"]
diff --git a/gas/testsuite/gas/i386/mwaitx-bdver4.d b/gas/testsuite/gas/i386/mwaitx-bdver4.d
new file mode 100644
index 00000000000..7a09db684d9
--- /dev/null
+++ b/gas/testsuite/gas/i386/mwaitx-bdver4.d
@@ -0,0 +1,17 @@
+#source: mwaitx.s
+#as: -march=bdver4
+#objdump: -dw
+#name: i386 monitorx and mwaitx insn
+
+.*: +file format .*
+
+
+Disassembly of section \.text:
+
+00000000 <_start>:
+[ 	]*[a-f0-9]+:	0f 01 fa             	monitorx %eax,%ecx,%edx
+[       ]*[a-f0-9]+:	67 0f 01 fa          	monitorx %ax,%ecx,%edx
+[ 	]*[a-f0-9]+:	0f 01 fa             	monitorx %eax,%ecx,%edx
+[ 	]*[a-f0-9]+:	0f 01 fb             	mwaitx %eax,%ecx,%ebx
+[ 	]*[a-f0-9]+:	0f 01 fb             	mwaitx %eax,%ecx,%ebx
+#pass
diff --git a/gas/testsuite/gas/i386/mwaitx-reg.l b/gas/testsuite/gas/i386/mwaitx-reg.l
new file mode 100644
index 00000000000..68ea6e98d63
--- /dev/null
+++ b/gas/testsuite/gas/i386/mwaitx-reg.l
@@ -0,0 +1,59 @@
+#as: -march=mwaitx
+.*: Assembler messages:
+#eax
+.*:[0-9]*: Error: .*eax.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*eax.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*eax.* 2 .*mwaitx.*
+.*:[0-9]*: Error: .*eax.* 3 .*mwaitx.*
+
+#ebx
+.*:[0-9]*: Error: .*ebx.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*ebx.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*ebx.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*ebx.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*ebx.* 2 .*mwaitx.*
+
+#ecx
+.*:[0-9]*: Error: .*ecx.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*ecx.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*ecx.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*ecx.* 3 .*mwaitx.*
+
+#edx
+.*:[0-9]*: Error: .*edx.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*edx.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*edx.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*edx.* 2 .*mwaitx.*
+.*:[0-9]*: Error: .*edx.* 3 .*mwaitx.*
+
+#esp
+.*:[0-9]*: Error: .*esp.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*esp.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*esp.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*esp.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*esp.* 2 .*mwaitx.*
+.*:[0-9]*: Error: .*esp.* 3 .*mwaitx.*
+
+#ebp
+.*:[0-9]*: Error: .*ebp.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*ebp.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*ebp.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*ebp.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*ebp.* 2 .*mwaitx.*
+.*:[0-9]*: Error: .*ebp.* 3 .*mwaitx.*
+
+#esi
+.*:[0-9]*: Error: .*esi.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*esi.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*esi.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*esi.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*esi.* 2 .*mwaitx.*
+.*:[0-9]*: Error: .*esi.* 3 .*mwaitx.*
+
+#edi
+.*:[0-9]*: Error: .*edi.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*edi.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*edi.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*edi.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*edi.* 2 .*mwaitx.*
+.*:[0-9]*: Error: .*edi.* 3 .*mwaitx.*
diff --git a/gas/testsuite/gas/i386/mwaitx-reg.s b/gas/testsuite/gas/i386/mwaitx-reg.s
new file mode 100644
index 00000000000..aa2e229972d
--- /dev/null
+++ b/gas/testsuite/gas/i386/mwaitx-reg.s
@@ -0,0 +1,8 @@
+.irp reg ax,bx,cx,dx,sp,bp,si,di
+	monitorx %e\reg, %ecx, %edx
+	monitorx %eax, %e\reg, %edx
+	monitorx %eax, %ecx, %e\reg
+	mwaitx %e\reg, %ecx, %ebx
+	mwaitx %eax, %e\reg, %ebx
+	mwaitx %eax, %ecx, %e\reg
+.endr
diff --git a/gas/testsuite/gas/i386/mwaitx.s b/gas/testsuite/gas/i386/mwaitx.s
new file mode 100644
index 00000000000..7bd7a3add23
--- /dev/null
+++ b/gas/testsuite/gas/i386/mwaitx.s
@@ -0,0 +1,9 @@
+# Check monitorx and mwaitx instructions
+
+	.text
+_start:
+	monitorx %eax, %ecx, %edx
+	monitorx %ax, %ecx, %edx
+	monitorx
+	mwaitx %eax, %ecx, %ebx
+	mwaitx
diff --git a/gas/testsuite/gas/i386/x86-64-arch-3-znver1.d b/gas/testsuite/gas/i386/x86-64-arch-3-znver1.d
index 906685543c5..2fc0a1f9340 100644
--- a/gas/testsuite/gas/i386/x86-64-arch-3-znver1.d
+++ b/gas/testsuite/gas/i386/x86-64-arch-3-znver1.d
@@ -18,4 +18,9 @@ Disassembly of section .text:
 [ 	]*[a-f0-9]+:	48 0f c7 21          	xsavec64 \(%rcx\)
 [ 	]*[a-f0-9]+:	48 0f c7 29          	xsaves64 \(%rcx\)
 [ 	]*[a-f0-9]+:	66 0f ae 39          	clflushopt \(%rcx\)
+[ 	]*[a-f0-9]+:	0f 01 fa             	monitorx %rax,%rcx,%rdx
+[ 	]*[a-f0-9]+:	67 0f 01 fa          	monitorx %eax,%rcx,%rdx
+[ 	]*[a-f0-9]+:	0f 01 fa             	monitorx %rax,%rcx,%rdx
+[ 	]*[a-f0-9]+:	0f 01 fb             	mwaitx %rax,%rcx,%rbx
+[ 	]*[a-f0-9]+:	0f 01 fb             	mwaitx %rax,%rcx,%rbx
 #pass
diff --git a/gas/testsuite/gas/i386/x86-64-arch-3.d b/gas/testsuite/gas/i386/x86-64-arch-3.d
index 7b0792ad1f0..6a7fb0032ff 100644
--- a/gas/testsuite/gas/i386/x86-64-arch-3.d
+++ b/gas/testsuite/gas/i386/x86-64-arch-3.d
@@ -1,4 +1,4 @@
-#as: -march=generic64+smap+adx+rdseed+clzero+sha+xsavec+xsaves+clflushopt
+#as: -march=generic64+smap+adx+rdseed+clzero+sha+xsavec+xsaves+clflushopt+mwaitx
 #objdump: -dw
 #name: x86-64 arch 3
 
@@ -17,4 +17,9 @@ Disassembly of section .text:
 [ 	]*[a-f0-9]+:	48 0f c7 21          	xsavec64 \(%rcx\)
 [ 	]*[a-f0-9]+:	48 0f c7 29          	xsaves64 \(%rcx\)
 [ 	]*[a-f0-9]+:	66 0f ae 39          	clflushopt \(%rcx\)
+[ 	]*[a-f0-9]+:	0f 01 fa             	monitorx %rax,%rcx,%rdx
+[ 	]*[a-f0-9]+:	67 0f 01 fa          	monitorx %eax,%rcx,%rdx
+[ 	]*[a-f0-9]+:	0f 01 fa             	monitorx %rax,%rcx,%rdx
+[ 	]*[a-f0-9]+:	0f 01 fb             	mwaitx %rax,%rcx,%rbx
+[ 	]*[a-f0-9]+:	0f 01 fb             	mwaitx %rax,%rcx,%rbx
 #pass
diff --git a/gas/testsuite/gas/i386/x86-64-arch-3.s b/gas/testsuite/gas/i386/x86-64-arch-3.s
index 76c4226eb30..2096efc6567 100644
--- a/gas/testsuite/gas/i386/x86-64-arch-3.s
+++ b/gas/testsuite/gas/i386/x86-64-arch-3.s
@@ -18,4 +18,8 @@ xsavec64        (%rcx)
 xsaves64        (%rcx)
 #CLFLUSHOPT
 clflushopt      (%rcx)
-
+monitorx %rax,%rcx,%rdx
+monitorx %eax,%rcx,%rdx
+monitorx
+mwaitx %rax,%rcx,%rbx
+mwaitx
diff --git a/gas/testsuite/gas/i386/x86-64-mwaitx-bdver4.d b/gas/testsuite/gas/i386/x86-64-mwaitx-bdver4.d
new file mode 100644
index 00000000000..f35ad119edd
--- /dev/null
+++ b/gas/testsuite/gas/i386/x86-64-mwaitx-bdver4.d
@@ -0,0 +1,17 @@
+#source: x86-64-mwaitx.s
+#as: -march=bdver4
+#objdump: -dw
+#name: x86_64 monitorx and mwaitx insn
+
+.*: +file format .*
+
+
+Disassembly of section \.text:
+
+0000000000000000 <_start>:
+[ 	]*[a-f0-9]+:	0f 01 fa             	monitorx %rax,%rcx,%rdx
+[ 	]*[a-f0-9]+:	67 0f 01 fa          	monitorx %eax,%rcx,%rdx
+[ 	]*[a-f0-9]+:	0f 01 fa             	monitorx %rax,%rcx,%rdx
+[ 	]*[a-f0-9]+:	0f 01 fb             	mwaitx %rax,%rcx,%rbx
+[ 	]*[a-f0-9]+:	0f 01 fb             	mwaitx %rax,%rcx,%rbx
+#pass
diff --git a/gas/testsuite/gas/i386/x86-64-mwaitx-reg.l b/gas/testsuite/gas/i386/x86-64-mwaitx-reg.l
new file mode 100644
index 00000000000..ea1fef026c2
--- /dev/null
+++ b/gas/testsuite/gas/i386/x86-64-mwaitx-reg.l
@@ -0,0 +1,123 @@
+#as: -march=mwaitx
+.*: Assembler messages:
+#rax
+.*:[0-9]*: Error: .*rax.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*rax.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*rax.* 2 .*mwaitx.*
+.*:[0-9]*: Error: .*rax.* 3 .*mwaitx.*
+
+#rbx
+.*:[0-9]*: Error: .*rbx.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*rbx.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*rbx.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*rbx.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*rbx.* 2 .*mwaitx.*
+
+#rcx
+.*:[0-9]*: Error: .*rcx.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*rcx.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*rcx.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*rcx.* 3 .*mwaitx.*
+
+#rdx
+.*:[0-9]*: Error: .*rdx.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*rdx.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*rdx.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*rdx.* 2 .*mwaitx.*
+.*:[0-9]*: Error: .*rdx.* 3 .*mwaitx.*
+
+#rsp
+.*:[0-9]*: Error: .*rsp.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*rsp.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*rsp.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*rsp.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*rsp.* 2 .*mwaitx.*
+.*:[0-9]*: Error: .*rsp.* 3 .*mwaitx.*
+
+#rbp
+.*:[0-9]*: Error: .*rbp.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*rbp.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*rbp.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*rbp.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*rbp.* 2 .*mwaitx.*
+.*:[0-9]*: Error: .*rbp.* 3 .*mwaitx.*
+
+#rsi
+.*:[0-9]*: Error: .*rsi.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*rsi.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*rsi.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*rsi.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*rsi.* 2 .*mwaitx.*
+.*:[0-9]*: Error: .*rsi.* 3 .*mwaitx.*
+
+#rdi
+.*:[0-9]*: Error: .*rdi.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*rdi.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*rdi.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*rdi.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*rdi.* 2 .*mwaitx.*
+.*:[0-9]*: Error: .*rdi.* 3 .*mwaitx.*
+
+#r8
+.*:[0-9]*: Error: .*r8.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*r8.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*r8.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*r8.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*r8.* 2 .*mwaitx.*
+.*:[0-9]*: Error: .*r8.* 3 .*mwaitx.*
+
+#r9
+.*:[0-9]*: Error: .*r9.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*r9.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*r9.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*r9.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*r9.* 2 .*mwaitx.*
+.*:[0-9]*: Error: .*r9.* 3 .*mwaitx.*
+
+#r10
+.*:[0-9]*: Error: .*r10.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*r10.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*r10.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*r10.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*r10.* 2 .*mwaitx.*
+.*:[0-9]*: Error: .*r10.* 3 .*mwaitx.*
+
+#r11
+.*:[0-9]*: Error: .*r11.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*r11.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*r11.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*r11.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*r11.* 2 .*mwaitx.*
+.*:[0-9]*: Error: .*r11.* 3 .*mwaitx.*
+
+#r12
+.*:[0-9]*: Error: .*r12.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*r12.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*r12.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*r12.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*r12.* 2 .*mwaitx.*
+.*:[0-9]*: Error: .*r12.* 3 .*mwaitx.*
+
+#r13
+.*:[0-9]*: Error: .*r13.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*r13.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*r13.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*r13.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*r13.* 2 .*mwaitx.*
+.*:[0-9]*: Error: .*r13.* 3 .*mwaitx.*
+
+#r14
+.*:[0-9]*: Error: .*r14.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*r14.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*r14.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*r14.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*r14.* 2 .*mwaitx.*
+.*:[0-9]*: Error: .*r14.* 3 .*mwaitx.*
+
+#r15
+.*:[0-9]*: Error: .*r15.* 1 .*monitorx.*
+.*:[0-9]*: Error: .*r15.* 2 .*monitorx.*
+.*:[0-9]*: Error: .*r15.* 3 .*monitorx.*
+.*:[0-9]*: Error: .*r15.* 1 .*mwaitx.*
+.*:[0-9]*: Error: .*r15.* 2 .*mwaitx.*
+.*:[0-9]*: Error: .*r15.* 3 .*mwaitx.*
diff --git a/gas/testsuite/gas/i386/x86-64-mwaitx-reg.s b/gas/testsuite/gas/i386/x86-64-mwaitx-reg.s
new file mode 100644
index 00000000000..5df5f8c7776
--- /dev/null
+++ b/gas/testsuite/gas/i386/x86-64-mwaitx-reg.s
@@ -0,0 +1,8 @@
+.irp reg ax,bx,cx,dx,sp,bp,si,di,8,9,10,11,12,13,14,15
+	monitorx %r\reg, %rcx, %rdx
+	monitorx %rax, %r\reg, %rdx
+	monitorx %rax, %rcx, %r\reg
+	mwaitx %r\reg, %rcx, %rbx
+	mwaitx %rax, %r\reg, %rbx
+	mwaitx %rax, %rcx, %r\reg
+.endr
diff --git a/gas/testsuite/gas/i386/x86-64-mwaitx.s b/gas/testsuite/gas/i386/x86-64-mwaitx.s
new file mode 100644
index 00000000000..0f58d3ce44f
--- /dev/null
+++ b/gas/testsuite/gas/i386/x86-64-mwaitx.s
@@ -0,0 +1,9 @@
+# Check monitorx and mwaitx instructions
+
+	.text
+_start:
+	monitorx %rax, %rcx, %rdx
+	monitorx %eax, %rcx, %rdx
+	monitorx
+	mwaitx %rax, %rcx, %rbx
+	mwaitx