[Qemu-devel] [PATCH 017/111] m68k: add 32bit and 64bit multiply

[Bryce Lanham <blanham@gmail.com>]

From: Laurent Vivier <laurent@vivier.eu>

This patch modify "mull" to support 64bit result, and to update
CC on 32bit operands.

Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
---
 target-m68k/helpers.h   |    4 +++
 target-m68k/op_helper.c |   66 +++++++++++++++++++++++++++++++++++++++++++++++
 target-m68k/translate.c |   36 +++++++++++++++++++++----
 3 files changed, 100 insertions(+), 6 deletions(-)

diff --git a/target-m68k/helpers.h b/target-m68k/helpers.h
index a158aee..ca2bf82 100644
--- a/target-m68k/helpers.h
+++ b/target-m68k/helpers.h
@@ -7,6 +7,10 @@ DEF_HELPER_2(divu, void, env, i32)
 DEF_HELPER_2(divs, void, env, i32)
 DEF_HELPER_1(divu64, void, env)
 DEF_HELPER_1(divs64, void, env)
+DEF_HELPER_3(mulu32_cc, i32, env, i32, i32)
+DEF_HELPER_3(muls32_cc, i32, env, i32, i32)
+DEF_HELPER_3(mulu64, i32, env, i32, i32)
+DEF_HELPER_3(muls64, i32, env, i32, i32)
 DEF_HELPER_3(addx_cc, i32, env, i32, i32)
 DEF_HELPER_3(subx_cc, i32, env, i32, i32)
 DEF_HELPER_3(shl_cc, i32, env, i32, i32)
diff --git a/target-m68k/op_helper.c b/target-m68k/op_helper.c
index 1bffe5d..a6c8148 100644
--- a/target-m68k/op_helper.c
+++ b/target-m68k/op_helper.c
@@ -318,3 +318,69 @@ void HELPER(divs64)(CPUState *env)
     }
     env->cc_dest = flags;
 }
+
+uint32_t HELPER(mulu32_cc)(CPUState *env, uint32_t op1, uint32_t op2)
+{
+    uint64_t res = (uint32_t)op1 * op2;
+    uint32_t flags;
+
+    flags = 0;
+    if (res >> 32)
+       flags |= CCF_V;
+    if ((uint32_t)res == 0)
+       flags |= CCF_Z;
+    if ((int32_t)res < 0)
+       flags |= CCF_N;
+    env->cc_dest = flags;
+
+    return res;
+}
+
+uint32_t HELPER(muls32_cc)(CPUState *env, uint32_t op1, uint32_t op2)
+{
+    int64_t res = (int32_t)op1 * (int32_t)op2;
+    uint32_t flags;
+
+    flags = 0;
+    if (res != (int64_t)(int32_t)res)
+       flags |= CCF_V;
+    if ((uint32_t)res == 0)
+       flags |= CCF_Z;
+    if ((int32_t)res < 0)
+       flags |= CCF_N;
+    env->cc_dest = flags;
+
+    return res;
+}
+
+uint32_t HELPER(mulu64)(CPUState *env, uint32_t op1, uint32_t op2)
+{
+    uint64_t res = (uint64_t)op1 * op2;
+    uint32_t flags;
+
+    env->quadh = res >> 32;
+    flags = 0;
+    if (res == 0)
+       flags |= CCF_Z;
+    if ((int64_t)res < 0)
+       flags |= CCF_N;
+    env->cc_dest = flags;
+
+    return res;
+}
+
+uint32_t HELPER(muls64)(CPUState *env, uint32_t op1, uint32_t op2)
+{
+    int64_t res = (uint64_t)(int32_t)op1 * (int32_t)op2;
+    uint32_t flags;
+
+    env->quadh = res >> 32;
+    flags = 0;
+    if (res == 0)
+       flags |= CCF_Z;
+    if (res < 0)
+       flags |= CCF_N;
+    env->cc_dest = flags;
+
+    return res;
+}
diff --git a/target-m68k/translate.c b/target-m68k/translate.c
index 1d84081..74faabf 100644
--- a/target-m68k/translate.c
+++ b/target-m68k/translate.c
@@ -1631,22 +1631,45 @@ DISAS_INSN(mull)
     TCGv reg;
     TCGv src1;
     TCGv dest;
+    TCGv regh;
 
     /* The upper 32 bits of the product are discarded, so
        muls.l and mulu.l are functionally equivalent.  */
     ext = lduw_code(s->pc);
     s->pc += 2;
-    if (ext & 0x87ff) {
-        gen_exception(s, s->pc - 4, EXCP_UNSUPPORTED);
-        return;
+    if (ext & 0x400) {
+       if (!m68k_feature(s->env, M68K_FEATURE_QUAD_MULDIV)) {
+           gen_exception(s, s->pc - 4, EXCP_UNSUPPORTED);
+           return;
+       }
+       reg = DREG(ext, 12);
+       regh = DREG(ext, 0);
+       SRC_EA(src1, OS_LONG, 0, NULL);
+       dest = tcg_temp_new();
+       if (ext & 0x800)
+           gen_helper_muls64(dest, cpu_env, src1, reg);
+       else
+           gen_helper_mulu64(dest, cpu_env, src1, reg);
+       tcg_gen_mov_i32(reg, dest);
+       tcg_gen_mov_i32(regh, QREG_QUADH);
+       s->cc_op = CC_OP_FLAGS;
+       return;
     }
     reg = DREG(ext, 12);
     SRC_EA(src1, OS_LONG, 0, NULL);
     dest = tcg_temp_new();
-    tcg_gen_mul_i32(dest, src1, reg);
+    if (m68k_feature(s->env, M68K_FEATURE_M68000)) {
+       if (ext & 0x800)
+           gen_helper_muls32_cc(dest, cpu_env, src1, reg);
+       else
+           gen_helper_mulu32_cc(dest, cpu_env, src1, reg);
+       s->cc_op = CC_OP_FLAGS;
+    } else {
+       tcg_gen_mul_i32(dest, src1, reg);
+       /* Unlike m68k, coldfire always clears the overflow bit.  */
+       gen_logic_cc(s, dest);
+    }
     tcg_gen_mov_i32(reg, dest);
-    /* Unlike m68k, coldfire always clears the overflow bit.  */
-    gen_logic_cc(s, dest);
 }
 
 DISAS_INSN(link)
@@ -3028,6 +3051,7 @@ void register_m68k_insns (CPUM68KState *env)
     INSN(illegal,   4afc, ffff, CF_ISA_A);
     INSN(illegal,   4afc, ffff, M68000);
     INSN(mull,      4c00, ffc0, CF_ISA_A);
+    INSN(mull,      4c00, ffc0, LONG_MULDIV);
     INSN(divl,      4c40, ffc0, CF_ISA_A);
     INSN(divl,      4c40, ffc0, LONG_MULDIV);
     INSN(sats,      4c80, fff8, CF_ISA_B);
-- 
1.7.2.3