Fix monster fallthrough in UNITS_CanAnimModeUseAttackRate

[ResurrectedTrader]

UNITS_CanAnimModeUseAttackRate has the same missing break as UNITS_CanAnimModeUseVelocityModifier: the UNIT_MONSTER case falls through into default: return FALSE;, so monster attacks never run at their attack rate (UNITS_UpdateAttackAnimRateAndVelocity).

1.10f

Inlined in UNITS_UpdateAnimRateAndVelocity (D2Common.0x6FDBF050, #10376). The velocity test above falls into this one (0x6FDBF3DE); the monster branch picks the table and goes on to the bCanUseAttackRate test:

6FDBF3DE  mov     edx, ecx
6FDBF3E0  sub     edx, 0
6FDBF3E3  jz      loc_6FDBF63D                      ; player
6FDBF3E9  dec     edx
6FDBF3EA  jz      loc_6FDBF61C                      ; monster
6FDBF3F0  test    ecx, ecx
6FDBF3F2  jz      loc_6FDBF81E
6FDBF3F8  cmp     ecx, 1
6FDBF3FB  jz      loc_6FDBF81E
6FDBF401  push    0BE9h
6FDBF406  push    6FDE5CF4h
6FDBF40B  push    6FDE5E9Ch
6FDBF410  call    6FDC4352h
6FDBF415  add     esp, 0Ch
6FDBF418  push    0FFFFFFFFh
6FDBF41A  call    6FDC446Fh

6FDBF61C  mov     edx, [esp+20h+var_C]
6FDBF620  cmp     edx, 19Ah                         ; <== monster: class >= 410
6FDBF626  lea     edx, [eax+eax*4]
6FDBF629  jge     short loc_6FDBF634
6FDBF62B  lea     edx, unk_6FDD2DB8[edx*4]          ; <== classic monster modulators
6FDBF632  jmp     short loc_6FDBF647                ; <== no return, go on to the test
6FDBF634  lea     edx, dword_6FDD2EF8[edx*4]        ; <== expansion monster modulators
6FDBF63B  jmp     short loc_6FDBF647                ; <== no return, go on to the test
6FDBF63D  lea     edx, [eax+eax*4]
6FDBF640  lea     edx, unk_6FDD2C28[edx*4]          ; player modulators
6FDBF647  mov     esi, [edx+0Ch]                    ; bCanUseAttackRate
6FDBF64A  test    esi, esi
6FDBF64C  jnz     short loc_6FDBF69B                ; -> attack rate
6FDBF64E  mov     esi, [edx+8]                      ; bCanUseSkillAttackRate
6FDBF651  test    esi, esi
6FDBF653  jz      loc_6FDBF81E
6FDBF659  mov     ecx, [ebp+0A8h]
6FDBF65F  call    sub_6FDAFF30                      ; used skill
6FDBF664  test    eax, eax
6FDBF666  jz      loc_6FDBF816
6FDBF66C  push    0BF4h
6FDBF671  push    6FDE5CF4h
6FDBF676  push    eax
6FDBF677  call    D2Common_10963
6FDBF67C  mov     ecx, eax
6FDBF67E  call    sub_6FD9E040
6FDBF683  mov     edx, ds:gdwBitMasks
6FDBF689  xor     ecx, ecx
6FDBF68B  mov     cl, [eax+6]
6FDBF68E  and     ecx, [edx+0Ch]                    ; SKILLSFLAG_USEATTACKRATE
6FDBF691  mov     [esp+20h+arg_8], ecx
6FDBF695  jz      loc_6FDBF816
6FDBF69B  push    1
6FDBF69D  push    ebp
6FDBF69E  call    D2Common_10440                    ; attack rate

1.14d

The same in Game.exe 0x621580:

00621580  push    ebp
00621581  mov     ebp, esp
00621583  mov     eax, edx
00621585  sub     eax, 0
00621588  jz      short loc_6215DB
0062158A  sub     eax, 1
0062158D  jz      short loc_6215BD                  ; monster
0062158F  test    edx, edx
00621591  jz      short loc_6215B7
00621593  cmp     edx, 1
00621596  jz      short loc_6215B7
00621598  push    0BEFh
0062159D  call    GetAddress
006215A2  push    eax
006215A3  push    offset Default
006215A8  call    ERROR_UnrecoverableInternalError_Halt
006215AD  add     esp, 0Ch
006215B0  push    0FFFFFFFFh
006215B2  call    _exit
006215B7  xor     eax, eax
006215B9  pop     ebp
006215BA  retn    8
006215BD  cmp     [ebp+arg_4], 19Ah                 ; <== monster: class >= 410
006215C4  lea     eax, [ecx+ecx*4]
006215C7  jge     short loc_6215D2
006215C9  lea     eax, unk_6E8B90[eax*4]            ; <== classic monster modulators
006215D0  jmp     short loc_6215E5
006215D2  lea     eax, unk_6E8CD0[eax*4]            ; <== expansion monster modulators
006215D9  jmp     short loc_6215E5
006215DB  lea     eax, [ecx+ecx*4]
006215DE  lea     eax, unk_6E8A00[eax*4]            ; player modulators
006215E5  cmp     dword ptr [eax+0Ch], 0            ; bCanUseAttackRate
006215E9  jz      short loc_6215F4
006215EB  mov     eax, 1
006215F0  pop     ebp
006215F1  retn    8

Change

Add the missing break;.

Once monsters reach the skill-attack-rate branch, they can hit the NULL used-skill dereference that is fixed separately in #244. The two should land together.

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