[PATCH v2 03/10] x86emul: handle AVX512-FP16 move insns

[Jan Beulich <jbeulich@xxxxxxxx>]

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

--- a/tools/tests/x86_emulator/evex-disp8.c
+++ b/tools/tests/x86_emulator/evex-disp8.c
@@ -622,6 +622,8 @@ static const struct test avx512_fp16_all
     INSN(maxsh,         f3, map5, 5f,    el, fp16, el),
     INSN(minph,           , map5, 5d,    vl, fp16, vl),
     INSN(minsh,         f3, map5, 5d,    el, fp16, el),
+    INSN(movsh,         f3, map5, 10,    el, fp16, el),
+    INSN(movsh,         f3, map5, 11,    el, fp16, el),
     INSN(mulph,           , map5, 59,    vl, fp16, vl),
     INSN(mulsh,         f3, map5, 59,    el, fp16, el),
     INSN(reduceph,        , 0f3a, 56,    vl, fp16, vl),
@@ -635,6 +637,11 @@ static const struct test avx512_fp16_all
     INSN(ucomish,         , map5, 2e,    el, fp16, el),
 };
 
+static const struct test avx512_fp16_128[] = {
+    INSN(movw, 66, map5, 6e, el, fp16, el),
+    INSN(movw, 66, map5, 7e, el, fp16, el),
+};
+
 static const struct test gfni_all[] = {
     INSN(gf2p8affineinvqb, 66, 0f3a, cf, vl, q, vl),
     INSN(gf2p8affineqb,    66, 0f3a, ce, vl, q, vl),
@@ -1039,6 +1046,7 @@ void evex_disp8_test(void *instr, struct
     RUN(avx512_vp2intersect, all);
     RUN(avx512_vpopcntdq, all);
     RUN(avx512_fp16, all);
+    RUN(avx512_fp16, 128);
 
     if ( cpu_has_avx512f )
     {
--- a/tools/tests/x86_emulator/predicates.c
+++ b/tools/tests/x86_emulator/predicates.c
@@ -2029,6 +2029,8 @@ static const struct evex {
     { { 0xce }, 3, T, R, pfx_66, W1, Ln }, /* vgf2p8affineqb */
     { { 0xcf }, 3, T, R, pfx_66, W1, Ln }, /* vgf2p8affineinvqb */
 }, evex_map5[] = {
+    { { 0x10 }, 2, T, R, pfx_f3, W0, LIG }, /* vmovsh */
+    { { 0x11 }, 2, T, W, pfx_f3, W0, LIG }, /* vmovsh */
     { { 0x2e }, 2, T, R, pfx_no, W0, LIG }, /* vucomish */
     { { 0x2f }, 2, T, R, pfx_no, W0, LIG }, /* vcomish */
     { { 0x51 }, 2, T, R, pfx_no, W0, Ln }, /* vsqrtph */
@@ -2045,6 +2047,8 @@ static const struct evex {
     { { 0x5e }, 2, T, R, pfx_f3, W0, LIG }, /* vdivsh */
     { { 0x5f }, 2, T, R, pfx_no, W0, Ln }, /* vmaxph */
     { { 0x5f }, 2, T, R, pfx_f3, W0, LIG }, /* vmaxsh */
+    { { 0x6e }, 2, T, R, pfx_66, WIG, L0 }, /* vmovw */
+    { { 0x7e }, 2, T, W, pfx_66, WIG, L0 }, /* vmovw */
 };
 
 static const struct {
--- a/tools/tests/x86_emulator/test_x86_emulator.c
+++ b/tools/tests/x86_emulator/test_x86_emulator.c
@@ -5140,6 +5140,76 @@ int main(int argc, char **argv)
     else
         printf("skipped\n");
 
+    printf("%-40s", "Testing vmovsh 8(%ecx),%xmm5...");
+    if ( stack_exec && cpu_has_avx512_fp16 )
+    {
+        decl_insn(vmovsh_from_mem);
+        decl_insn(vmovw_to_gpr);
+
+        asm volatile ( "vpcmpeqw %%ymm5, %%ymm5, %%ymm5\n\t"
+                       put_insn(vmovsh_from_mem,
+                                /* vmovsh 8(%0), %%xmm5 */
+                                ".byte 0x62, 0xf5, 0x7e, 0x08\n\t"
+                                ".byte 0x10, 0x69, 0x04")
+                       :: "c" (NULL) );
+
+        set_insn(vmovsh_from_mem);
+        res[2] = 0x3c00bc00;
+        regs.ecx = (unsigned long)res;
+        rc = x86_emulate(&ctxt, &emulops);
+        if ( (rc != X86EMUL_OKAY) || !check_eip(vmovsh_from_mem) )
+            goto fail;
+        asm volatile ( "kmovw     %2, %%k1\n\t"
+                       "vmovdqu16 %1, %%zmm4%{%%k1%}%{z%}\n\t"
+                       "vpcmpeqw  %%zmm4, %%zmm5, %%k0\n\t"
+                       "kmovw     %%k0, %0"
+                       : "=g" (rc)
+                       : "m" (res[2]), "r" (1) );
+        if ( rc != 0xffff )
+            goto fail;
+        printf("okay\n");
+
+        printf("%-40s", "Testing vmovsh %xmm4,2(%eax){%k3}...");
+        memset(res, ~0, 8);
+        res[2] = 0xbc00ffff;
+        memset(res + 3, ~0, 8);
+        regs.eax = (unsigned long)res;
+        regs.ecx = ~0;
+        for ( i = 0; i < 2; ++i )
+        {
+            decl_insn(vmovsh_to_mem);
+
+            asm volatile ( "kmovw %1, %%k3\n\t"
+                           put_insn(vmovsh_to_mem,
+                                    /* vmovsh %%xmm4, 2(%0)%{%%k3%} */
+                                    ".byte 0x62, 0xf5, 0x7e, 0x0b\n\t"
+                                    ".byte 0x11, 0x60, 0x01")
+                           :: "a" (NULL), "r" (i) );
+
+            set_insn(vmovsh_to_mem);
+            rc = x86_emulate(&ctxt, &emulops);
+            if ( (rc != X86EMUL_OKAY) || !check_eip(vmovsh_to_mem) ||
+                 memcmp(res, res + 3 - i, 8) )
+                goto fail;
+        }
+        printf("okay\n");
+
+        printf("%-40s", "Testing vmovw %xmm5,%ecx...");
+        asm volatile ( put_insn(vmovw_to_gpr,
+                                /* vmovw %%xmm5, %0 */
+                                ".byte 0x62, 0xf5, 0x7d, 0x08\n\t"
+                                ".byte 0x7e, 0xe9")
+                       :: "c" (NULL) );
+        set_insn(vmovw_to_gpr);
+        rc = x86_emulate(&ctxt, &emulops);
+        if ( (rc != X86EMUL_OKAY) || !check_eip(vmovw_to_gpr) ||
+             regs.ecx != 0xbc00 )
+            goto fail;
+        printf("okay\n");
+    }
+    else
+        printf("skipped\n");
+
     printf("%-40s", "Testing invpcid 16(%ecx),%%edx...");
     if ( stack_exec )
     {
--- a/xen/arch/x86/x86_emulate/decode.c
+++ b/xen/arch/x86/x86_emulate/decode.c
@@ -585,7 +585,7 @@ static unsigned int decode_disp8scale(en
         break;
 
     case d8s_dq64:
-        return 2 + (s->op_bytes == 8);
+        return 1 + !s->fp16 + (s->op_bytes == 8);
     }
 
     switch ( s->simd_size )
@@ -1469,6 +1469,15 @@ int x86emul_decode(struct x86_emulate_st
                     s->fp16 = true;
                 s->simd_size = simd_none;
                 break;
+
+            case 0x6e: /* vmovw r/m16, xmm */
+                d = (d & ~SrcMask) | SrcMem16;
+                /* fall through */
+            case 0x7e: /* vmovw xmm, r/m16 */
+                if ( s->evex.pfx == vex_66 )
+                    s->fp16 = true;
+                s->simd_size = simd_none;
+                break;
             }
 
             /* Like above re-use twobyte_table[] here. */
--- a/xen/arch/x86/x86_emulate/x86_emulate.c
+++ b/xen/arch/x86/x86_emulate/x86_emulate.c
@@ -4390,6 +4390,15 @@ x86_emulate(
 
 #ifndef X86EMUL_NO_SIMD
 
+    case X86EMUL_OPC_EVEX_66(5, 0x7e): /* vmovw xmm,r/m16 */
+        ASSERT(dst.bytes >= 4);
+        if ( dst.type == OP_MEM )
+            dst.bytes = 2;
+        /* fall through */
+    case X86EMUL_OPC_EVEX_66(5, 0x6e): /* vmovw r/m16,xmm */
+        host_and_vcpu_must_have(avx512_fp16);
+        generate_exception_if(evex.w, EXC_UD);
+        /* fall through */
     case X86EMUL_OPC_EVEX_66(0x0f, 0x6e): /* vmov{d,q} r/m,xmm */
     case X86EMUL_OPC_EVEX_66(0x0f, 0x7e): /* vmov{d,q} xmm,r/m */
         generate_exception_if((evex.lr || evex.opmsk || evex.brs ||
@@ -7745,8 +7754,18 @@ x86_emulate(
 
 #ifndef X86EMUL_NO_SIMD
 
+    case X86EMUL_OPC_EVEX_F3(5, 0x10):   /* vmovsh m16,xmm{k} */
+                                         /* vmovsh xmm,xmm,xmm{k} */
+    case X86EMUL_OPC_EVEX_F3(5, 0x11):   /* vmovsh xmm,m16{k} */
+                                         /* vmovsh xmm,xmm,xmm{k} */
+        generate_exception_if(evex.brs, EXC_UD);
+        if ( ea.type == OP_MEM )
+            d |= TwoOp;
+        else
+        {
     case X86EMUL_OPC_EVEX_F3(5, 0x51):   /* vsqrtsh xmm/m16,xmm,xmm{k} */
-        d &= ~TwoOp;
+            d &= ~TwoOp;
+        }
         /* fall through */
     case X86EMUL_OPC_EVEX(5, 0x51):      /* vsqrtph [xyz]mm/mem,[xyz]mm{k} */
     CASE_SIMD_SINGLE_FP(_EVEX, 5, 0x58): /* vadd{p,s}h 
[xyz]mm/mem,[xyz]mm,[xyz]mm{k} */