cmd/compile: cull some dead arch-specific Ops

Change-Id: Iee7daa5b91b7896ce857321e307f2ee47b7f095f
Reviewed-on: https://go-review.googlesource.com/36906
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

src/cmd/compile/internal/gc/fmt.go

@@ -163,7 +163,6 @@ var goopnames = []string{
 	OCOM:      "^",
 	OCONTINUE: "continue",
 	OCOPY:     "copy",
-	ODEC:      "--",
 	ODELETE:   "delete",
 	ODEFER:    "defer",
 	ODIV:      "/",
@@ -175,7 +174,6 @@ var goopnames = []string{
 	OGT:       ">",
 	OIF:       "if",
 	OIMAG:     "imag",
-	OINC:      "++",
 	OIND:      "*",
 	OLEN:      "len",
 	OLE:       "<=",

src/cmd/compile/internal/gc/opnames.go

@@ -152,15 +152,8 @@ var opnames = []string{
 	OVARKILL:         "VARKILL",
 	OVARLIVE:         "VARLIVE",
 	OINDREGSP:        "INDREGSP",
-	OCMP:             "CMP",
-	ODEC:             "DEC",
-	OINC:             "INC",
-	OEXTEND:          "EXTEND",
 	OHMUL:            "HMUL",
-	ORROTC:           "RROTC",
 	ORETJMP:          "RETJMP",
-	OPS:              "PS",
-	OPC:              "PC",
 	OGETG:            "GETG",
 	OEND:             "END",
 }

src/cmd/compile/internal/gc/racewalk.go

@@ -369,11 +369,6 @@ func instrumentnode(np **Node, init *Nodes, wr int, skip int) {
 
 		goto ret
 
-		// impossible nodes: only appear in backend.
-	case ORROTC, OEXTEND:
-		yyerror("instrument: %v cannot exist now", n.Op)
-		goto ret
-
 	case OGETG:
 		yyerror("instrument: OGETG can happen only in runtime which we don't instrument")
 		goto ret

src/cmd/compile/internal/gc/syntax.go

@@ -494,15 +494,8 @@ const (
 	OINDREGSP   // offset plus indirect of REGSP, such as 8(SP).
 
 	// arch-specific opcodes
-	OCMP    // compare: ACMP.
-	ODEC    // decrement: ADEC.
-	OINC    // increment: AINC.
-	OEXTEND // extend: ACWD/ACDQ/ACQO.
 	OHMUL   // high mul: AMUL/AIMUL for unsigned/signed (OMUL uses AIMUL for both).
-	ORROTC  // right rotate-carry: ARCR.
 	ORETJMP // return to other function
-	OPS     // compare parity set (for x86 NaN check)
-	OPC     // compare parity clear (for x86 NaN check)
 	OGETG   // runtime.getg() (read g pointer)
 
 	OEND