[PATCH 1/3] x86: limit use of XOP2SOURCES

[Jan Beulich <jbeulich@suse.com>]

The VPROT* forms with an immediate operand are entirely standard in the
way their ModR/M bytes are built. There's no reason to invoke special
case code. With that the handling of an immediate there can also be
dropped; it was partially bogus anyway, as in its "no memory operands"
portion it ignores the possibility of an immediate operand (which was
okay only because that case was already handled by more generic code).

--- a/gas/config/tc-i386.c
+++ b/gas/config/tc-i386.c
@@ -8620,17 +8620,11 @@ build_modrm_byte (void)
 
       if (i.tm.opcode_modifier.vexsources == XOP2SOURCES)
 	{
-	  if (operand_type_check (i.types[0], imm))
-	    i.vex.register_specifier = NULL;
+	  /* VEX.vvvv encodes one of the sources.  */
+	  if (i.tm.opcode_modifier.vexw == VEXW0)
+	    i.vex.register_specifier = i.op[0].regs;
 	  else
-	    {
-	      /* VEX.vvvv encodes one of the sources when the first
-		 operand is not an immediate.  */
-	      if (i.tm.opcode_modifier.vexw == VEXW0)
-		i.vex.register_specifier = i.op[0].regs;
-	      else
-		i.vex.register_specifier = i.op[1].regs;
-	    }
+	    i.vex.register_specifier = i.op[1].regs;
 
 	  /* Destination is a XMM register encoded in the ModRM.reg
 	     and VEX.R bit.  */
--- a/opcodes/i386-opc.tbl
+++ b/opcodes/i386-opc.tbl
@@ -1877,7 +1877,7 @@ vpmadcsswd, 0xa6, XOP, Modrm|SpaceXOP08|
 vpmadcswd, 0xb6, XOP, Modrm|SpaceXOP08|VexSources=2|VexVVVV=1|VexW=1|NoSuf|Vex, { RegXMM, RegXMM|Unspecified|BaseIndex, RegXMM, RegXMM }
 vpperm, 0xa3, XOP, D|Modrm|SpaceXOP08|VexSources=2|VexVVVV|VexW0|NoSuf|Vex, { RegXMM, RegXMM|Unspecified|BaseIndex, RegXMM, RegXMM }
 vprot<xop>, 0x90 | <xop:opc>, XOP, D|Modrm|Vex128|SpaceXOP09|VexW0|VexSources=1|NoSuf, { RegXMM, RegXMM|Unspecified|BaseIndex, RegXMM }
-vprot<xop>, 0xc0 | <xop:opc>, XOP, Modrm|Vex128|SpaceXOP08|VexW0|VexSources=1|NoSuf, { Imm8, RegXMM|Unspecified|BaseIndex, RegXMM }
+vprot<xop>, 0xc0 | <xop:opc>, XOP, Modrm|Vex128|SpaceXOP08|VexW0|NoSuf, { Imm8, RegXMM|Unspecified|BaseIndex, RegXMM }
 vpsha<xop>, 0x98 | <xop:opc>, XOP, D|Modrm|Vex128|SpaceXOP09|VexW0|VexSources=1|NoSuf, { RegXMM, RegXMM|Unspecified|BaseIndex, RegXMM }
 vpshl<xop>, 0x94 | <xop:opc>, XOP, D|Modrm|Vex128|SpaceXOP09|VexW0|VexSources=1|NoSuf, { RegXMM, RegXMM|Unspecified|BaseIndex, RegXMM }