x86: Encode EVEX instructions with VEX128 if possible

If EVEX encoding isn't required, we can encode EVEX instructions with
VEX128.

	* config/tc-i386.c (optimize_encoding): Encode EVEX instructions
	with VEX128 if EVEX encoding isn't required.
	* testsuite/gas/i386/optimize-1.d: Updated.
	* testsuite/gas/i386/x86-64-optimize-2.d: Likewise.

4 files changed, 33 insertions, 25 deletions

diff --git a/gas/ChangeLog b/gas/ChangeLog
index 2fe224c..166e24e 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,5 +1,12 @@
 2018-03-09  H.J. Lu  <hongjiu.lu@intel.com>
 
+	* config/tc-i386.c (optimize_encoding): Encode EVEX instructions
+	with VEX128 if EVEX encoding isn't required.
+	* testsuite/gas/i386/optimize-1.d: Updated.
+	* testsuite/gas/i386/x86-64-optimize-2.d: Likewise.
+
+2018-03-09  H.J. Lu  <hongjiu.lu@intel.com>
+
 	* config/tc-i386.c (check_VecOperations): Strip whitespace.
 	* testsuite/gas/i386/optimize-1.s: Add whitespaces before
 	{%k7} and {z},
diff --git a/gas/config/tc-i386.c b/gas/config/tc-i386.c
index 7243760..e94e01c 100644
--- a/gas/config/tc-i386.c
+++ b/gas/config/tc-i386.c
@@ -3875,7 +3875,8 @@ optimize_encoding (void)
 	       || (!i.mask
 		   && !i.rounding
 		   && is_evex_encoding (&i.tm)
-		   && (i.tm.cpu_flags.bitfield.cpuavx512vl
+		   && (i.vec_encoding != vex_encoding_evex
+		       || i.tm.cpu_flags.bitfield.cpuavx512vl
 		       || cpu_arch_isa_flags.bitfield.cpuavx512vl)))
 	   && ((i.tm.base_opcode == 0x55
 		|| i.tm.base_opcode == 0x6655
diff --git a/gas/testsuite/gas/i386/optimize-1.d b/gas/testsuite/gas/i386/optimize-1.d
index f7da296..3ea6e75 100644
--- a/gas/testsuite/gas/i386/optimize-1.d
+++ b/gas/testsuite/gas/i386/optimize-1.d
@@ -10,52 +10,52 @@ Disassembly of section .text:
 0+ <_start>:
  +[a-f0-9]+:	62 f1 f5 4f 55 e9    	vandnpd %zmm1,%zmm1,%zmm5\{%k7\}
  +[a-f0-9]+:	62 f1 f5 af 55 e9    	vandnpd %ymm1,%ymm1,%ymm5\{%k7\}\{z\}
- +[a-f0-9]+:	62 f1 f5 48 55 e9    	vandnpd %zmm1,%zmm1,%zmm5
+ +[a-f0-9]+:	c5 f1 55 e9          	vandnpd %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	c5 f1 55 e9          	vandnpd %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	62 f1 74 4f 55 e9    	vandnps %zmm1,%zmm1,%zmm5\{%k7\}
  +[a-f0-9]+:	62 f1 74 af 55 e9    	vandnps %ymm1,%ymm1,%ymm5\{%k7\}\{z\}
- +[a-f0-9]+:	62 f1 74 48 55 e9    	vandnps %zmm1,%zmm1,%zmm5
+ +[a-f0-9]+:	c5 f0 55 e9          	vandnps %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	c5 f0 55 e9          	vandnps %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	c5 f1 df e9          	vpandn %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	62 f1 75 4f df e9    	vpandnd %zmm1,%zmm1,%zmm5\{%k7\}
  +[a-f0-9]+:	62 f1 75 af df e9    	vpandnd %ymm1,%ymm1,%ymm5\{%k7\}\{z\}
- +[a-f0-9]+:	62 f1 75 48 df e9    	vpandnd %zmm1,%zmm1,%zmm5
+ +[a-f0-9]+:	c5 f1 df e9          	vpandn %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	c5 f1 df e9          	vpandn %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	62 f1 f5 4f df e9    	vpandnq %zmm1,%zmm1,%zmm5\{%k7\}
  +[a-f0-9]+:	62 f1 f5 af df e9    	vpandnq %ymm1,%ymm1,%ymm5\{%k7\}\{z\}
- +[a-f0-9]+:	62 f1 f5 48 df e9    	vpandnq %zmm1,%zmm1,%zmm5
+ +[a-f0-9]+:	c5 f1 df e9          	vpandn %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	c5 f1 df e9          	vpandn %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	62 f1 f5 4f 57 e9    	vxorpd %zmm1,%zmm1,%zmm5\{%k7\}
  +[a-f0-9]+:	62 f1 f5 af 57 e9    	vxorpd %ymm1,%ymm1,%ymm5\{%k7\}\{z\}
- +[a-f0-9]+:	62 f1 f5 48 57 e9    	vxorpd %zmm1,%zmm1,%zmm5
+ +[a-f0-9]+:	c5 f1 57 e9          	vxorpd %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	c5 f1 57 e9          	vxorpd %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	62 f1 74 4f 57 e9    	vxorps %zmm1,%zmm1,%zmm5\{%k7\}
  +[a-f0-9]+:	62 f1 74 af 57 e9    	vxorps %ymm1,%ymm1,%ymm5\{%k7\}\{z\}
- +[a-f0-9]+:	62 f1 74 48 57 e9    	vxorps %zmm1,%zmm1,%zmm5
+ +[a-f0-9]+:	c5 f0 57 e9          	vxorps %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	c5 f0 57 e9          	vxorps %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	c5 f1 ef e9          	vpxor  %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	62 f1 75 4f ef e9    	vpxord %zmm1,%zmm1,%zmm5\{%k7\}
  +[a-f0-9]+:	62 f1 75 af ef e9    	vpxord %ymm1,%ymm1,%ymm5\{%k7\}\{z\}
- +[a-f0-9]+:	62 f1 75 48 ef e9    	vpxord %zmm1,%zmm1,%zmm5
+ +[a-f0-9]+:	c5 f1 ef e9          	vpxor  %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	c5 f1 ef e9          	vpxor  %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	62 f1 f5 4f ef e9    	vpxorq %zmm1,%zmm1,%zmm5\{%k7\}
  +[a-f0-9]+:	62 f1 f5 af ef e9    	vpxorq %ymm1,%ymm1,%ymm5\{%k7\}\{z\}
- +[a-f0-9]+:	62 f1 f5 48 ef e9    	vpxorq %zmm1,%zmm1,%zmm5
+ +[a-f0-9]+:	c5 f1 ef e9          	vpxor  %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	c5 f1 ef e9          	vpxor  %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	62 f1 75 4f f8 e9    	vpsubb %zmm1,%zmm1,%zmm5\{%k7\}
  +[a-f0-9]+:	62 f1 75 af f8 e9    	vpsubb %ymm1,%ymm1,%ymm5\{%k7\}\{z\}
- +[a-f0-9]+:	62 f1 75 48 f8 e9    	vpsubb %zmm1,%zmm1,%zmm5
+ +[a-f0-9]+:	c5 f1 f8 e9          	vpsubb %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	c5 f1 f8 e9          	vpsubb %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	62 f1 75 4f f9 e9    	vpsubw %zmm1,%zmm1,%zmm5\{%k7\}
  +[a-f0-9]+:	62 f1 75 af f9 e9    	vpsubw %ymm1,%ymm1,%ymm5\{%k7\}\{z\}
- +[a-f0-9]+:	62 f1 75 48 f9 e9    	vpsubw %zmm1,%zmm1,%zmm5
+ +[a-f0-9]+:	c5 f1 f9 e9          	vpsubw %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	c5 f1 f9 e9          	vpsubw %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	62 f1 75 4f fa e9    	vpsubd %zmm1,%zmm1,%zmm5\{%k7\}
  +[a-f0-9]+:	62 f1 75 af fa e9    	vpsubd %ymm1,%ymm1,%ymm5\{%k7\}\{z\}
- +[a-f0-9]+:	62 f1 75 48 fa e9    	vpsubd %zmm1,%zmm1,%zmm5
+ +[a-f0-9]+:	c5 f1 fa e9          	vpsubd %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	c5 f1 fa e9          	vpsubd %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	62 f1 f5 4f fb e9    	vpsubq %zmm1,%zmm1,%zmm5\{%k7\}
  +[a-f0-9]+:	62 f1 f5 af fb e9    	vpsubq %ymm1,%ymm1,%ymm5\{%k7\}\{z\}
- +[a-f0-9]+:	62 f1 f5 48 fb e9    	vpsubq %zmm1,%zmm1,%zmm5
+ +[a-f0-9]+:	c5 f1 fb e9          	vpsubq %xmm1,%xmm1,%xmm5
  +[a-f0-9]+:	c5 f1 fb e9          	vpsubq %xmm1,%xmm1,%xmm5
 #pass
diff --git a/gas/testsuite/gas/i386/x86-64-optimize-2.d b/gas/testsuite/gas/i386/x86-64-optimize-2.d
index 9222efe..ba3a2df 100644
--- a/gas/testsuite/gas/i386/x86-64-optimize-2.d
+++ b/gas/testsuite/gas/i386/x86-64-optimize-2.d
@@ -10,7 +10,7 @@ Disassembly of section .text:
 0+ <_start>:
  +[a-f0-9]+:	62 71 f5 4f 55 f9    	vandnpd %zmm1,%zmm1,%zmm15\{%k7\}
  +[a-f0-9]+:	62 71 f5 af 55 f9    	vandnpd %ymm1,%ymm1,%ymm15\{%k7\}\{z\}
- +[a-f0-9]+:	62 71 f5 48 55 f9    	vandnpd %zmm1,%zmm1,%zmm15
+ +[a-f0-9]+:	c5 71 55 f9          	vandnpd %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	c5 71 55 f9          	vandnpd %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	62 e1 f5 48 55 c1    	vandnpd %zmm1,%zmm1,%zmm16
  +[a-f0-9]+:	62 e1 f5 08 55 c1    	vandnpd %xmm1,%xmm1,%xmm16
@@ -18,7 +18,7 @@ Disassembly of section .text:
  +[a-f0-9]+:	62 b1 f5 00 55 c9    	vandnpd %xmm17,%xmm17,%xmm1
  +[a-f0-9]+:	62 71 74 4f 55 f9    	vandnps %zmm1,%zmm1,%zmm15\{%k7\}
  +[a-f0-9]+:	62 71 74 af 55 f9    	vandnps %ymm1,%ymm1,%ymm15\{%k7\}\{z\}
- +[a-f0-9]+:	62 71 74 48 55 f9    	vandnps %zmm1,%zmm1,%zmm15
+ +[a-f0-9]+:	c5 70 55 f9          	vandnps %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	c5 70 55 f9          	vandnps %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	62 e1 74 48 55 c1    	vandnps %zmm1,%zmm1,%zmm16
  +[a-f0-9]+:	62 e1 74 08 55 c1    	vandnps %xmm1,%xmm1,%xmm16
@@ -27,7 +27,7 @@ Disassembly of section .text:
  +[a-f0-9]+:	c5 71 df f9          	vpandn %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	62 71 75 4f df f9    	vpandnd %zmm1,%zmm1,%zmm15\{%k7\}
  +[a-f0-9]+:	62 71 75 af df f9    	vpandnd %ymm1,%ymm1,%ymm15\{%k7\}\{z\}
- +[a-f0-9]+:	62 71 75 48 df f9    	vpandnd %zmm1,%zmm1,%zmm15
+ +[a-f0-9]+:	c5 71 df f9          	vpandn %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	c5 71 df f9          	vpandn %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	62 e1 75 48 df c1    	vpandnd %zmm1,%zmm1,%zmm16
  +[a-f0-9]+:	62 e1 75 08 df c1    	vpandnd %xmm1,%xmm1,%xmm16
@@ -35,7 +35,7 @@ Disassembly of section .text:
  +[a-f0-9]+:	62 b1 75 00 df c9    	vpandnd %xmm17,%xmm17,%xmm1
  +[a-f0-9]+:	62 71 f5 4f df f9    	vpandnq %zmm1,%zmm1,%zmm15\{%k7\}
  +[a-f0-9]+:	62 71 f5 af df f9    	vpandnq %ymm1,%ymm1,%ymm15\{%k7\}\{z\}
- +[a-f0-9]+:	62 71 f5 48 df f9    	vpandnq %zmm1,%zmm1,%zmm15
+ +[a-f0-9]+:	c5 71 df f9          	vpandn %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	c5 71 df f9          	vpandn %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	62 e1 f5 48 df c1    	vpandnq %zmm1,%zmm1,%zmm16
  +[a-f0-9]+:	62 e1 f5 08 df c1    	vpandnq %xmm1,%xmm1,%xmm16
@@ -43,7 +43,7 @@ Disassembly of section .text:
  +[a-f0-9]+:	62 b1 f5 00 df c9    	vpandnq %xmm17,%xmm17,%xmm1
  +[a-f0-9]+:	62 71 f5 4f 57 f9    	vxorpd %zmm1,%zmm1,%zmm15\{%k7\}
  +[a-f0-9]+:	62 71 f5 af 57 f9    	vxorpd %ymm1,%ymm1,%ymm15\{%k7\}\{z\}
- +[a-f0-9]+:	62 71 f5 48 57 f9    	vxorpd %zmm1,%zmm1,%zmm15
+ +[a-f0-9]+:	c5 71 57 f9          	vxorpd %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	c5 71 57 f9          	vxorpd %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	62 e1 f5 48 57 c1    	vxorpd %zmm1,%zmm1,%zmm16
  +[a-f0-9]+:	62 e1 f5 08 57 c1    	vxorpd %xmm1,%xmm1,%xmm16
@@ -51,7 +51,7 @@ Disassembly of section .text:
  +[a-f0-9]+:	62 b1 f5 00 57 c9    	vxorpd %xmm17,%xmm17,%xmm1
  +[a-f0-9]+:	62 71 74 4f 57 f9    	vxorps %zmm1,%zmm1,%zmm15\{%k7\}
  +[a-f0-9]+:	62 71 74 af 57 f9    	vxorps %ymm1,%ymm1,%ymm15\{%k7\}\{z\}
- +[a-f0-9]+:	62 71 74 48 57 f9    	vxorps %zmm1,%zmm1,%zmm15
+ +[a-f0-9]+:	c5 70 57 f9          	vxorps %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	c5 70 57 f9          	vxorps %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	62 e1 74 48 57 c1    	vxorps %zmm1,%zmm1,%zmm16
  +[a-f0-9]+:	62 e1 74 08 57 c1    	vxorps %xmm1,%xmm1,%xmm16
@@ -60,7 +60,7 @@ Disassembly of section .text:
  +[a-f0-9]+:	c5 71 ef f9          	vpxor  %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	62 71 75 4f ef f9    	vpxord %zmm1,%zmm1,%zmm15\{%k7\}
  +[a-f0-9]+:	62 71 75 af ef f9    	vpxord %ymm1,%ymm1,%ymm15\{%k7\}\{z\}
- +[a-f0-9]+:	62 71 75 48 ef f9    	vpxord %zmm1,%zmm1,%zmm15
+ +[a-f0-9]+:	c5 71 ef f9          	vpxor  %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	c5 71 ef f9          	vpxor  %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	62 e1 75 48 ef c1    	vpxord %zmm1,%zmm1,%zmm16
  +[a-f0-9]+:	62 e1 75 08 ef c1    	vpxord %xmm1,%xmm1,%xmm16
@@ -68,7 +68,7 @@ Disassembly of section .text:
  +[a-f0-9]+:	62 b1 75 00 ef c9    	vpxord %xmm17,%xmm17,%xmm1
  +[a-f0-9]+:	62 71 f5 4f ef f9    	vpxorq %zmm1,%zmm1,%zmm15\{%k7\}
  +[a-f0-9]+:	62 71 f5 af ef f9    	vpxorq %ymm1,%ymm1,%ymm15\{%k7\}\{z\}
- +[a-f0-9]+:	62 71 f5 48 ef f9    	vpxorq %zmm1,%zmm1,%zmm15
+ +[a-f0-9]+:	c5 71 ef f9          	vpxor  %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	c5 71 ef f9          	vpxor  %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	62 e1 f5 48 ef c1    	vpxorq %zmm1,%zmm1,%zmm16
  +[a-f0-9]+:	62 e1 f5 08 ef c1    	vpxorq %xmm1,%xmm1,%xmm16
@@ -76,7 +76,7 @@ Disassembly of section .text:
  +[a-f0-9]+:	62 b1 f5 00 ef c9    	vpxorq %xmm17,%xmm17,%xmm1
  +[a-f0-9]+:	62 71 75 4f f8 f9    	vpsubb %zmm1,%zmm1,%zmm15\{%k7\}
  +[a-f0-9]+:	62 71 75 af f8 f9    	vpsubb %ymm1,%ymm1,%ymm15\{%k7\}\{z\}
- +[a-f0-9]+:	62 71 75 48 f8 f9    	vpsubb %zmm1,%zmm1,%zmm15
+ +[a-f0-9]+:	c5 71 f8 f9          	vpsubb %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	c5 71 f8 f9          	vpsubb %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	62 e1 75 48 f8 c1    	vpsubb %zmm1,%zmm1,%zmm16
  +[a-f0-9]+:	62 e1 75 08 f8 c1    	vpsubb %xmm1,%xmm1,%xmm16
@@ -84,7 +84,7 @@ Disassembly of section .text:
  +[a-f0-9]+:	62 b1 75 00 f8 c9    	vpsubb %xmm17,%xmm17,%xmm1
  +[a-f0-9]+:	62 71 75 4f f9 f9    	vpsubw %zmm1,%zmm1,%zmm15\{%k7\}
  +[a-f0-9]+:	62 71 75 af f9 f9    	vpsubw %ymm1,%ymm1,%ymm15\{%k7\}\{z\}
- +[a-f0-9]+:	62 71 75 48 f9 f9    	vpsubw %zmm1,%zmm1,%zmm15
+ +[a-f0-9]+:	c5 71 f9 f9          	vpsubw %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	c5 71 f9 f9          	vpsubw %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	62 e1 75 48 f9 c1    	vpsubw %zmm1,%zmm1,%zmm16
  +[a-f0-9]+:	62 e1 75 08 f9 c1    	vpsubw %xmm1,%xmm1,%xmm16
@@ -92,7 +92,7 @@ Disassembly of section .text:
  +[a-f0-9]+:	62 b1 75 00 f9 c9    	vpsubw %xmm17,%xmm17,%xmm1
  +[a-f0-9]+:	62 71 75 4f fa f9    	vpsubd %zmm1,%zmm1,%zmm15\{%k7\}
  +[a-f0-9]+:	62 71 75 af fa f9    	vpsubd %ymm1,%ymm1,%ymm15\{%k7\}\{z\}
- +[a-f0-9]+:	62 71 75 48 fa f9    	vpsubd %zmm1,%zmm1,%zmm15
+ +[a-f0-9]+:	c5 71 fa f9          	vpsubd %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	c5 71 fa f9          	vpsubd %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	62 e1 75 48 fa c1    	vpsubd %zmm1,%zmm1,%zmm16
  +[a-f0-9]+:	62 e1 75 08 fa c1    	vpsubd %xmm1,%xmm1,%xmm16
@@ -100,7 +100,7 @@ Disassembly of section .text:
  +[a-f0-9]+:	62 b1 75 00 fa c9    	vpsubd %xmm17,%xmm17,%xmm1
  +[a-f0-9]+:	62 71 f5 4f fb f9    	vpsubq %zmm1,%zmm1,%zmm15\{%k7\}
  +[a-f0-9]+:	62 71 f5 af fb f9    	vpsubq %ymm1,%ymm1,%ymm15\{%k7\}\{z\}
- +[a-f0-9]+:	62 71 f5 48 fb f9    	vpsubq %zmm1,%zmm1,%zmm15
+ +[a-f0-9]+:	c5 71 fb f9          	vpsubq %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	c5 71 fb f9          	vpsubq %xmm1,%xmm1,%xmm15
  +[a-f0-9]+:	62 e1 f5 48 fb c1    	vpsubq %zmm1,%zmm1,%zmm16
  +[a-f0-9]+:	62 e1 f5 08 fb c1    	vpsubq %xmm1,%xmm1,%xmm16