ndisasm: handle VEX.LIG

A lot of instructions ignore the L bit in the VEX prefix, just like
a lot of instructions ignore the W bit, so don't use them in the
sub-table select.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

diff --git a/disasm.c b/disasm.c
index 81282e6..ba282d3 100644 (file)
--- a/disasm.c
+++ b/disasm.c
@@ -1081,7 +1081,7 @@ int32_t disasm(uint8_t *data, char *output, int outbufsize, int segsize,
                    prefix.vex_lp = prefix.vex[1] & 7;
                }
 
-               ix = itable_vex[RV_VEX][prefix.vex_m][prefix.vex_lp];
+               ix = itable_vex[RV_VEX][prefix.vex_m][prefix.vex_lp & 3];
            }
            end_prefix = true;
            break;

diff --git a/insns.h b/insns.h
index 4ae2499..4f3dd80 100644 (file)
--- a/insns.h
+++ b/insns.h
@@ -32,7 +32,7 @@ struct disasm_index {
 /* Tables for the assembler and disassembler, respectively */
 extern const struct itemplate * const nasm_instructions[];
 extern const struct disasm_index itable[256];
-extern const struct disasm_index * const itable_vex[2][32][8];
+extern const struct disasm_index * const itable_vex[2][32][4];
 
 /* Common table for the byte codes */
 extern const uint8_t nasm_bytecodes[];

diff --git a/insns.pl b/insns.pl
index 3313a6c..adc1814 100755 (executable)
--- a/insns.pl
+++ b/insns.pl
@@ -52,8 +52,8 @@ $vex_classes = scalar(@vex_class);
 for ($c = 0; $c < $vex_classes; $c++) {
     $vexmap{$vex_class[$c]} = $c;
     for ($m = 0; $m < 32; $m++) {
-       for ($lp = 0; $lp < 8; $lp++) {
-           push(@vexlist, sprintf("%s%02X%01X", $vex_class[$c], $m, $lp));
+       for ($p = 0; $p < 4; $p++) {
+           push(@vexlist, sprintf("%s%02X%01X", $vex_class[$c], $m, $p));
        }
     }
 }
@@ -319,15 +319,15 @@ if ( !defined($output) || $output eq 'd' ) {
        print D "};\n";
     }
 
-    printf D "\nconst struct disasm_index * const itable_vex[%d][32][8] =\n",
+    printf D "\nconst struct disasm_index * const itable_vex[%d][32][4] =\n",
         $vex_classes;
     print D "{\n";
     for ($c = 0; $c < $vex_classes; $c++) {
        print D "    {\n";
        for ($m = 0; $m < 32; $m++) {
            print D "        {\n";
-           for ($lp = 0; $lp < 8; $lp++) {
-               $vp = sprintf("%s%02X%01X", $vex_class[$c], $m, $lp);
+           for ($p = 0; $p < 4; $p++) {
+               $vp = sprintf("%s%02X%01X", $vex_class[$c], $m, $p);
                if ($is_prefix{$vp}) {
                    printf D "            itable_%s,\n", $vp;
                } else {
@@ -628,7 +628,7 @@ sub startseq($$) {
            $wlp = shift(@codes);
            $c = ($m >> 6);
            $m = $m & 31;
-           $prefix .= sprintf('%s%02X%01X', $vex_class[$c], $m, $wlp & 7);
+           $prefix .= sprintf('%s%02X%01X', $vex_class[$c], $m, $wlp & 3);
        } elsif ($c0 >= 0172 && $c0 <= 174) {
            shift(@codes);      # Skip is4 control byte
        } else {