gwj / at91sam9263 · Commits

Commit ff8263a951c5ce22bef919c792d20e5cbf5066b3

Authored by bellard
1 parent 04d81be8

ARM saturating arithmetic fixes (Paul Brook) 


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@1431 c046a42c-6fe2-441c-8c8c-71466251a162
Inline Side-by-side
Showing 2 changed files with 22 additions and 10 deletions
target-arm/op.c
  View file @ff8263a
... ... @@ -805,6 +805,23 @@ void OPPROTO op_subl_T0_T1_saturate(void)
805 805 FORCE_RET();
806 806 }
807 807  
  808 +void OPPROTO op_double_T1_saturate(void)
  809 +{
  810 + int32_t val;
  811 +
  812 + val = T1;
  813 + if (val >= 0x40000000) {
  814 + T1 = 0x7fffffff;
  815 + env->QF = 1;
  816 + } else if (val <= (int32_t)0xc0000000) {
  817 + T1 = 0x80000000;
  818 + env->QF = 1;
  819 + } else {
  820 + T1 = val << 1;
  821 + }
  822 + FORCE_RET();
  823 +}
  824 +
808 825 /* thumb shift by immediate */
809 826 void OPPROTO op_shll_T0_im_thumb(void)
810 827 {
... ...
target-arm/translate.c
  View file @ff8263a
... ... @@ -1019,20 +1019,15 @@ static void disas_arm_insn(CPUState * env, DisasContext *s)
1019 1019 case 0x5: /* saturating add/subtract */
1020 1020 rd = (insn >> 12) & 0xf;
1021 1021 rn = (insn >> 16) & 0xf;
1022   - gen_movl_T0_reg(s, rn);
1023   - if (op1 & 2) {
1024   - gen_movl_T1_reg(s, rn);
1025   - if (op1 & 1)
1026   - gen_op_subl_T0_T1_saturate();
1027   - else
1028   - gen_op_addl_T0_T1_saturate();
1029   - }
1030   - gen_movl_T1_reg(s, rm);
  1022 + gen_movl_T0_reg(s, rm);
  1023 + gen_movl_T1_reg(s, rn);
  1024 + if (op1 & 2)
  1025 + gen_op_double_T1_saturate();
1031 1026 if (op1 & 1)
1032 1027 gen_op_subl_T0_T1_saturate();
1033 1028 else
1034 1029 gen_op_addl_T0_T1_saturate();
1035   - gen_movl_reg_T0(s, rn);
  1030 + gen_movl_reg_T0(s, rd);
1036 1031 break;
1037 1032 case 0x8: /* signed multiply */
1038 1033 case 0xa:
... ...