[src/trunk]: src/lib/libnvmm Revert (REPE) CMPS support per request of Maxime...

[reinoud <reinoud%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/54967ac23f18
branches:  trunk
changeset: 977723:54967ac23f18
user:      reinoud <reinoud%NetBSD.org@localhost>
date:      Sat Oct 31 15:44:01 2020 +0000

description:
Revert (REPE) CMPS support per request of Maxime, it is incorrect.

diffstat:

 lib/libnvmm/libnvmm_x86.c |  64 +---------------------------------------------
 1 files changed, 2 insertions(+), 62 deletions(-)

diffs (107 lines):

diff -r c44582cc3b50 -r 54967ac23f18 lib/libnvmm/libnvmm_x86.c
--- a/lib/libnvmm/libnvmm_x86.c Sat Oct 31 15:23:52 2020 +0000
+++ b/lib/libnvmm/libnvmm_x86.c Sat Oct 31 15:44:01 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: libnvmm_x86.c,v 1.41 2020/10/30 21:06:13 reinoud Exp $ */
+/*     $NetBSD: libnvmm_x86.c,v 1.42 2020/10/31 15:44:01 reinoud Exp $ */
 
 /*
  * Copyright (c) 2018-2020 Maxime Villard, m00nbsd.net
@@ -1051,7 +1051,6 @@
        bool movs:1;
        bool stos:1;
        bool lods:1;
-       bool cmps:1;
        bool szoverride:1;
        bool group1:1;
        bool group3:1;
@@ -1464,26 +1463,6 @@
        },
 
        /*
-        * CMPS
-        */
-       [0xA6] = {
-               /* Yb, Xb */
-               .valid = true,
-               .cmps = true,
-               .szoverride = false,
-               .defsize = OPSIZE_BYTE,
-               .emul = &x86_emul_cmp
-       },
-       [0xA7] = {
-               /* Yv, Xv */
-               .valid = true,
-               .cmps = true,
-               .szoverride = true,
-               .defsize = -1,
-               .emul = &x86_emul_cmp
-       },
-
-       /*
         * STOS
         */
        [0xAA] = {
@@ -1892,35 +1871,6 @@
 }
 
 /*
- * Special node, for CMPS. Fake two displacements of zero on the source and
- * destination registers.
- * XXX coded as clone of movs as its similar in register usage
- * XXX might be merged with node_movs()
- */
-static int
-node_cmps(struct x86_decode_fsm *fsm, struct x86_instr *instr)
-{
-       size_t adrsize;
-
-       adrsize = instr->address_size;
-
-       /* DS:RSI */
-       instr->src.type = STORE_REG;
-       instr->src.u.reg = &gpr_map__special[1][2][adrsize-1];
-       instr->src.disp.type = DISP_0;
-
-       /* ES:RDI, force ES */
-       instr->dst.type = STORE_REG;
-       instr->dst.u.reg = &gpr_map__special[1][3][adrsize-1];
-       instr->dst.disp.type = DISP_0;
-       instr->dst.hardseg = NVMM_X64_SEG_ES;
-
-       fsm_advance(fsm, 0, NULL);
-
-       return 0;
-}
-
-/*
  * Special node, for STOS and LODS. Fake a displacement of zero on the
  * destination register.
  */
@@ -2520,8 +2470,6 @@
                fsm_advance(fsm, 1, node_stlo);
        } else if (opcode->movs) {
                fsm_advance(fsm, 1, node_movs);
-       } else if (opcode->cmps) {
-               fsm_advance(fsm, 1, node_cmps);
        } else {
                return -1;
        }
@@ -2698,16 +2646,8 @@
 
        while (fsm.fn != NULL) {
                ret = (*fsm.fn)(&fsm, instr);
-               if (ret == -1) {
-                       printf("\nNVMM: %s missing support for instruction " \
-                              "with max length %ld : [ ", __func__,
-                              inst_len);
-                       for (uint i = 0; i < inst_len; i++)
-                               printf("%02x ", inst_bytes[i]);
-                       printf("], please report to NetBSD!\n\n");
-                       fflush(stdout);
+               if (ret == -1)
                        return -1;
-               }
        }
 
        instr->len = fsm.buf - inst_bytes;