float fixes - added bsr/bsf support

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@23 c046a42c-6fe2-441c-8c8c-71466251a162

Makefile

@@ -83,6 +83,7 @@ cpu-i386.h   gemu.h      op-i386.c         syscall-i386.h  translate-i386.c\
 dis-asm.h    gen-i386.h  op-i386.h         syscall.c\
 dis-buf.c    i386-dis.c  opreg_template.h  syscall_defs.h\
 i386.ld ppc.ld\
+tests/Makefile\
 tests/test-i386.c tests/test-i386-shift.h tests/test-i386.h\
 tests/test-i386-muldiv.h\
 tests/test2.c tests/hello.c tests/sha1.c tests/test1.c

TODO

@@ -3,4 +3,4 @@
 - threads
 - fix printf for doubles (fp87.c bug ?)
 - make it self runnable (use same trick as ld.so : include its own relocator and libc)
-- better FPU comparisons (ucom/com)
+- fix FPU exceptions (in particular: gen_op_fpush not before mem load)

cpu-i386.h

@@ -114,7 +114,7 @@ enum {
 };
 
 #ifdef __i386__
-#define USE_X86LDOUBLE
+//#define USE_X86LDOUBLE
 #endif
 
 #ifdef USE_X86LDOUBLE
@@ -201,7 +201,7 @@ static inline void stl(void *ptr, int v)
     *(uint32_t *)ptr = v;
 }
 
-static inline void stq(void *ptr, int v)
+static inline void stq(void *ptr, uint64_t v)
 {
     *(uint64_t *)ptr = v;
 }

op-i386.c

@@ -1055,7 +1055,7 @@ typedef union {
 
 #else
 
-typedef {
+typedef union {
     double d;
 #ifndef WORDS_BIGENDIAN
     struct {
@@ -1119,6 +1119,31 @@ void OPPROTO op_fldl_ST0_A0(void)
     ST0 = ldfq((void *)A0);
 }
 
+#ifdef USE_X86LDOUBLE
+void OPPROTO op_fldt_ST0_A0(void)
+{
+    ST0 = *(long double *)A0;
+}
+#else
+void helper_fldt_ST0_A0(void)
+{
+    CPU86_LDoubleU temp;
+    int upper, e;
+    /* mantissa */
+    upper = lduw((uint8_t *)A0 + 8);
+    /* XXX: handle overflow ? */
+    e = (upper & 0x7fff) - 16383 + EXPBIAS; /* exponent */
+    e |= (upper >> 4) & 0x800; /* sign */
+    temp.ll = ((ldq((void *)A0) >> 11) & ((1LL << 52) - 1)) | ((uint64_t)e << 52);
+    ST0 = temp.d;
+}
+
+void OPPROTO op_fldt_ST0_A0(void)
+{
+    helper_fldt_ST0_A0();
+}
+#endif
+
 void OPPROTO op_fild_ST0_A0(void)
 {
     ST0 = (CPU86_LDouble)ldsw((void *)A0);
@@ -1143,9 +1168,34 @@ void OPPROTO op_fsts_ST0_A0(void)
 
 void OPPROTO op_fstl_ST0_A0(void)
 {
-    ST0 = ldfq((void *)A0);
+    stfq((void *)A0, (double)ST0);
 }
 
+#ifdef USE_X86LDOUBLE
+void OPPROTO op_fstt_ST0_A0(void)
+{
+    *(long double *)A0 = ST0;
+}
+#else
+void helper_fstt_ST0_A0(void)
+{
+    CPU86_LDoubleU temp;
+    int e;
+    temp.d = ST0;
+    /* mantissa */
+    stq((void *)A0, (MANTD(temp) << 11) | (1LL << 63));
+    /* exponent + sign */
+    e = EXPD(temp) - EXPBIAS + 16383;
+    e |= SIGND(temp) >> 16;
+    stw((uint8_t *)A0 + 8, e);
+}
+
+void OPPROTO op_fstt_ST0_A0(void)
+{
+    helper_fstt_ST0_A0();
+}
+#endif
+
 void OPPROTO op_fist_ST0_A0(void)
 {
     int val;
@@ -1167,6 +1217,103 @@ void OPPROTO op_fistll_ST0_A0(void)
     stq((void *)A0, val);
 }
 
+/* BCD ops */
+
+#define MUL10(iv) ( iv + iv + (iv << 3) )
+
+void helper_fbld_ST0_A0(void)
+{
+    uint8_t *seg;
+    CPU86_LDouble fpsrcop;
+    int m32i;
+    unsigned int v;
+
+    /* in this code, seg/m32i will be used as temporary ptr/int */
+    seg = (uint8_t *)A0 + 8;
+    v = ldub(seg--);
+    /* XXX: raise exception */
+    if (v != 0)
+        return;
+    v = ldub(seg--);
+    /* XXX: raise exception */
+    if ((v & 0xf0) != 0)
+        return;
+    m32i = v;  /* <-- d14 */
+    v = ldub(seg--);
+    m32i = MUL10(m32i) + (v >> 4);  /* <-- val * 10 + d13 */
+    m32i = MUL10(m32i) + (v & 0xf); /* <-- val * 10 + d12 */
+    v = ldub(seg--);
+    m32i = MUL10(m32i) + (v >> 4);  /* <-- val * 10 + d11 */
+    m32i = MUL10(m32i) + (v & 0xf); /* <-- val * 10 + d10 */
+    v = ldub(seg--);
+    m32i = MUL10(m32i) + (v >> 4);  /* <-- val * 10 + d9 */
+    m32i = MUL10(m32i) + (v & 0xf); /* <-- val * 10 + d8 */
+    fpsrcop = ((CPU86_LDouble)m32i) * 100000000.0;
+
+    v = ldub(seg--);
+    m32i = (v >> 4);  /* <-- d7 */
+    m32i = MUL10(m32i) + (v & 0xf); /* <-- val * 10 + d6 */
+    v = ldub(seg--);
+    m32i = MUL10(m32i) + (v >> 4);  /* <-- val * 10 + d5 */
+    m32i = MUL10(m32i) + (v & 0xf); /* <-- val * 10 + d4 */
+    v = ldub(seg--);
+    m32i = MUL10(m32i) + (v >> 4);  /* <-- val * 10 + d3 */
+    m32i = MUL10(m32i) + (v & 0xf); /* <-- val * 10 + d2 */
+    v = ldub(seg);
+    m32i = MUL10(m32i) + (v >> 4);  /* <-- val * 10 + d1 */
+    m32i = MUL10(m32i) + (v & 0xf); /* <-- val * 10 + d0 */
+    fpsrcop += ((CPU86_LDouble)m32i);
+    if ( ldub(seg+9) & 0x80 )
+        fpsrcop = -fpsrcop;
+    ST0 = fpsrcop;
+}
+
+void OPPROTO op_fbld_ST0_A0(void)
+{
+    helper_fbld_ST0_A0();
+}
+
+void helper_fbst_ST0_A0(void)
+{
+    CPU86_LDouble fptemp;
+    CPU86_LDouble fpsrcop;
+    int v;
+    uint8_t *mem_ref, *mem_end;
+
+    fpsrcop = rint(ST0);
+    mem_ref = (uint8_t *)A0;
+    mem_end = mem_ref + 8;
+    if ( fpsrcop < 0.0 ) {
+        stw(mem_end, 0x8000);
+        fpsrcop = -fpsrcop;
+    } else {
+        stw(mem_end, 0x0000);
+    }
+    while (mem_ref < mem_end) {
+        if (fpsrcop == 0.0)
+            break;
+        fptemp = floor(fpsrcop/10.0);
+        v = ((int)(fpsrcop - fptemp*10.0));
+        if  (fptemp == 0.0)  { 
+            stb(mem_ref++, v); 
+            break; 
+        }
+        fpsrcop = fptemp;
+        fptemp = floor(fpsrcop/10.0);
+        v |= (((int)(fpsrcop - fptemp*10.0)) << 4);
+        stb(mem_ref++, v);
+        fpsrcop = fptemp;
+    }
+    while (mem_ref < mem_end) {
+        stb(mem_ref++, 0);
+    }
+}
+
+void OPPROTO op_fbst_ST0_A0(void)
+{
+    helper_fbst_ST0_A0();
+}
+
 /* FPU move */
 
 static inline void fpush(void)
@@ -1244,6 +1391,17 @@ void OPPROTO op_fcom_ST0_FT0(void)
     FORCE_RET();
 }
 
+/* XXX: handle nans */
+void OPPROTO op_fucom_ST0_FT0(void)
+{
+    env->fpus &= (~0x4500);	/* (C3,C2,C0) <-- 000 */
+    if (ST0 < FT0)
+        env->fpus |= 0x100;	/* (C3,C2,C0) <-- 001 */
+    else if (ST0 == FT0)
+        env->fpus |= 0x4000; /* (C3,C2,C0) <-- 100 */
+    FORCE_RET();
+}
+
 void OPPROTO op_fadd_ST0_FT0(void)
 {
     ST0 += FT0;
@@ -1321,7 +1479,7 @@ void OPPROTO op_fabs_ST0(void)
     ST0 = fabs(ST0);
 }
 
-void OPPROTO op_fxam_ST0(void)
+void helper_fxam_ST0(void)
 {
     CPU86_LDoubleU temp;
     int expdif;
@@ -1346,7 +1504,11 @@ void OPPROTO op_fxam_ST0(void)
     } else {
         env->fpus |= 0x400;
     }
-    FORCE_RET();
+}
+
+void OPPROTO op_fxam_ST0(void)
+{
+    helper_fxam_ST0();
 }
 
 void OPPROTO op_fld1_ST0(void)
@@ -1354,12 +1516,12 @@ void OPPROTO op_fld1_ST0(void)
     ST0 = *(CPU86_LDouble *)&f15rk[1];
 }
 
-void OPPROTO op_fld2t_ST0(void)
+void OPPROTO op_fldl2t_ST0(void)
 {
     ST0 = *(CPU86_LDouble *)&f15rk[6];
 }
 
-void OPPROTO op_fld2e_ST0(void)
+void OPPROTO op_fldl2e_ST0(void)
 {
     ST0 = *(CPU86_LDouble *)&f15rk[5];
 }
@@ -1681,6 +1843,13 @@ void OPPROTO op_fnstsw_A0(void)
     stw((void *)A0, fpus);
 }
 
+void OPPROTO op_fnstsw_EAX(void)
+{
+    int fpus;
+    fpus = (env->fpus & ~0x3800) | (env->fpstt & 0x7) << 11;
+    EAX = (EAX & 0xffff0000) | fpus;
+}
+
 void OPPROTO op_fnstcw_A0(void)
 {
     stw((void *)A0, env->fpuc);
@@ -1784,6 +1953,10 @@ int cpu_x86_exec(CPUX86State *env1)
                         eflags & CC_P ? 'P' : '-',
                         eflags & CC_C ? 'C' : '-'
                         );
+#if 1
+                fprintf(logfile, "ST0=%f ST1=%f ST2=%f ST3=%f\n", 
+                        (double)ST0, (double)ST1, (double)ST(2), (double)ST(3));
+#endif
             }
 #endif
             cpu_x86_gen_code(code_gen_buffer, &code_gen_size, (uint8_t *)env->pc);

ops_template.h

@@ -633,6 +633,42 @@ void OPPROTO glue(glue(op_btc, SUFFIX), _T0_T1_cc)(void)
     T0 ^= (1 << count);
 }
 
+void OPPROTO glue(glue(op_bsf, SUFFIX), _T0_cc)(void)
+{
+    int res, count;
+    res = T0 & DATA_MASK;
+    if (res != 0) {
+        count = 0;
+        while ((res & 1) == 0) {
+            count++;
+            res >>= 1;
+        }
+        T0 = count;
+        CC_DST = 1; /* ZF = 1 */
+    } else {
+        CC_DST = 0; /* ZF = 1 */
+    }
+    FORCE_RET();
+}
+
+void OPPROTO glue(glue(op_bsr, SUFFIX), _T0_cc)(void)
+{
+    int res, count;
+    res = T0 & DATA_MASK;
+    if (res != 0) {
+        count = DATA_BITS - 1;
+        while ((res & SIGN_MASK) == 0) {
+            count--;
+            res <<= 1;
+        }
+        T0 = count;
+        CC_DST = 1; /* ZF = 1 */
+    } else {
+        CC_DST = 0; /* ZF = 1 */
+    }
+    FORCE_RET();
+}
+
 #endif
 
 /* string operations */

translate-i386.c

@@ -431,6 +431,17 @@ static GenOpFunc *gen_op_btx_T0_T1_cc[2][4] = {
     },
 };
 
+static GenOpFunc *gen_op_bsx_T0_cc[2][2] = {
+    [0] = {
+        gen_op_bsfw_T0_cc,
+        gen_op_bsrw_T0_cc,
+    },
+    [1] = {
+        gen_op_bsfl_T0_cc,
+        gen_op_bsrl_T0_cc,
+    },
+};
+
 static GenOpFunc *gen_op_lds_T0_A0[3] = {
     gen_op_ldsb_T0_A0,
     gen_op_ldsw_T0_A0,
@@ -652,15 +663,16 @@ static GenOpFunc *gen_op_fp_arith_ST0_FT0[8] = {
     gen_op_fdivr_ST0_FT0,
 };
 
+/* NOTE the exception in "r" op ordering */
 static GenOpFunc1 *gen_op_fp_arith_STN_ST0[8] = {
     gen_op_fadd_STN_ST0,
     gen_op_fmul_STN_ST0,
     NULL,
     NULL,
-    gen_op_fsub_STN_ST0,
     gen_op_fsubr_STN_ST0,
-    gen_op_fdiv_STN_ST0,
+    gen_op_fsub_STN_ST0,
     gen_op_fdivr_STN_ST0,
+    gen_op_fdiv_STN_ST0,
 };
 
 static void gen_op(DisasContext *s1, int op, int ot, int d, int s)
@@ -1866,13 +1878,25 @@ long disas_insn(DisasContext *s, uint8_t *pc_start, int *is_jmp_ptr)
             case 0x0f: /* fnstcw mem */
                 gen_op_fnstcw_A0();
                 break;
+            case 0x1d: /* fldt mem */
+                gen_op_fpush();
+                gen_op_fldt_ST0_A0();
+                break;
+            case 0x1f: /* fstpt mem */
+                gen_op_fstt_ST0_A0();
+                gen_op_fpop();
+                break;
             case 0x2f: /* fnstsw mem */
                 gen_op_fnstsw_A0();
                 break;
             case 0x3c: /* fbld */
+                gen_op_fpush();
+                op_fbld_ST0_A0();
+                break;
             case 0x3e: /* fbstp */
-                error("float BCD not hanlded");
+                gen_op_fbst_ST0_A0();
-                return -1;
+                gen_op_fpop();
+                break;
             case 0x3d: /* fildll */
                 gen_op_fpush();
                 gen_op_fildll_ST0_A0();
@@ -1882,7 +1906,7 @@ long disas_insn(DisasContext *s, uint8_t *pc_start, int *is_jmp_ptr)
                 gen_op_fpop();
                 break;
             default:
-                error("unhandled memory FP [op=0x%02x]\n", op);
+                error("unhandled FPm [op=0x%02x]\n", op);
                 return -1;
             }
         } else {
@@ -1895,7 +1919,7 @@ long disas_insn(DisasContext *s, uint8_t *pc_start, int *is_jmp_ptr)
                 gen_op_fmov_ST0_STN((opreg + 1) & 7);
                 break;
             case 0x09: /* fxchg sti */
-                gen_op_fxchg_ST0_STN((opreg + 1) & 7);
+                gen_op_fxchg_ST0_STN(opreg);
                 break;
             case 0x0a: /* grp d9/2 */
                 switch(rm) {
@@ -1929,24 +1953,31 @@ long disas_insn(DisasContext *s, uint8_t *pc_start, int *is_jmp_ptr)
                 {
                     switch(rm) {
                     case 0:
+                        gen_op_fpush();
                         gen_op_fld1_ST0();
                         break;
                     case 1:
-                        gen_op_fld2t_ST0();
+                        gen_op_fpush();
+                        gen_op_fldl2t_ST0();
                         break;
                     case 2:
-                        gen_op_fld2e_ST0();
+                        gen_op_fpush();
+                        gen_op_fldl2e_ST0();
                         break;
                     case 3:
+                        gen_op_fpush();
                         gen_op_fldpi_ST0();
                         break;
                     case 4:
+                        gen_op_fpush();
                         gen_op_fldlg2_ST0();
                         break;
                     case 5:
+                        gen_op_fpush();
                         gen_op_fldln2_ST0();
                         break;
                     case 6:
+                        gen_op_fpush();
                         gen_op_fldz_ST0();
                         break;
                     default:
@@ -2021,12 +2052,12 @@ long disas_insn(DisasContext *s, uint8_t *pc_start, int *is_jmp_ptr)
                     op1 = op & 7;
                     if (op >= 0x20) {
                         gen_op_fp_arith_STN_ST0[op1](opreg);
+                        if (op >= 0x30)
+                            gen_op_fpop();
                     } else {
                         gen_op_fmov_FT0_STN(opreg);
                         gen_op_fp_arith_ST0_FT0[op1]();
                     }
-                    if (op >= 0x30)
-                        gen_op_fpop();
                 }
                 break;
             case 0x02: /* fcom */
@@ -2042,7 +2073,7 @@ long disas_insn(DisasContext *s, uint8_t *pc_start, int *is_jmp_ptr)
                 switch(rm) {
                 case 1: /* fucompp */
                     gen_op_fmov_FT0_STN(1);
-                    gen_op_fcom_ST0_FT0();
+                    gen_op_fucom_ST0_FT0();
                     gen_op_fpop();
                     gen_op_fpop();
                     break;
@@ -2057,6 +2088,15 @@ long disas_insn(DisasContext *s, uint8_t *pc_start, int *is_jmp_ptr)
                 gen_op_fmov_STN_ST0(opreg);
                 gen_op_fpop();
                 break;
+            case 0x2c: /* fucom st(i) */
+                gen_op_fmov_FT0_STN(opreg);
+                gen_op_fucom_ST0_FT0();
+                break;
+            case 0x2d: /* fucomp st(i) */
+                gen_op_fmov_FT0_STN(opreg);
+                gen_op_fucom_ST0_FT0();
+                gen_op_fpop();
+                break;
             case 0x33: /* de/3 */
                 switch(rm) {
                 case 1: /* fcompp */
@@ -2071,18 +2111,16 @@ long disas_insn(DisasContext *s, uint8_t *pc_start, int *is_jmp_ptr)
                 break;
             case 0x3c: /* df/4 */
                 switch(rm) {
-#if 0
                 case 0:
-                    gen_insn3(OP_FNSTS, OR_EAX, OR_ZERO, OR_ZERO);
+                    gen_op_fnstsw_EAX();
                     break;
-#endif
                 default:
-                    error("unhandled FP df/4\n");
+                    error("unhandled FP %x df/4\n", rm);
                     return -1;
                 }
                 break;
             default:
-                error("unhandled FP\n");
+                error("unhandled FPr [op=0x%x]\n", op);
                 return -1;
             }
         }
@@ -2413,7 +2451,18 @@ long disas_insn(DisasContext *s, uint8_t *pc_start, int *is_jmp_ptr)
                 gen_op_mov_reg_T0[ot][rm]();
         }
         break;
-
+    case 0x1bc: /* bsf */
+    case 0x1bd: /* bsr */
+        ot = dflag ? OT_LONG : OT_WORD;
+        modrm = ldub(s->pc++);
+        reg = (modrm >> 3) & 7;
+        gen_ldst_modrm(s, modrm, ot, OR_TMP0, 0);
+        gen_op_bsx_T0_cc[ot - OT_WORD][b & 1]();
+        /* NOTE: we always write back the result. Intel doc says it is
+           undefined if T0 == 0 */
+        gen_op_mov_reg_T0[ot][reg]();
+        s->cc_op = CC_OP_LOGICB + ot;
+        break;
         /************************/
         /* misc */
     case 0x90: /* nop */