[Issue 15629] [REG] wrong code with "-O -inline" but correct with "-O"

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=15629

--- Comment #2 from Ivan Kazmenko <gassa at mail.ru> ---
Turned out that array b is also not necessary.

A bit less code (testmodule2.d):
-----
import std.math;
import std.stdio;

void main ()
{
    int [] a = [3];
    int value = abs (a[0]);
    if (a[0] != 3)
    {
        writeln (value, " ", a);
        assert (false);
    }
}
-----

Disassembly:
-----
__Dmain PROC NEAR
;  COMDEF __Dmain
        sub     esp, 36                                 ; 0000 _ 83. EC, 24
        mov     eax, 3                                  ; 0003 _ B8, 00000003
        mov     ecx, 1                                  ; 0008 _ B9, 00000001
        mov     dword ptr [esp+0CH], ebx                ; 000D _ 89. 5C 24, 0C
        mov     dword ptr [esp+10H], esi                ; 0011 _ 89. 74 24, 10
        mov     dword ptr [esp+18H], eax                ; 0015 _ 89. 44 24, 18
        mov     dword ptr [esp+4H], ecx                 ; 0019 _ 89. 4C 24, 04
        mov     dword ptr [esp], offset FLAT:_D11TypeInfo_Ai6__initZ; 001D _
C7. 04 24, 00000000(segrel)
        call    __d_arrayliteralTX                      ; 0024 _ E8,
00000000(rel)
        mov     edx, eax                                ; 0029 _ 89. C2
        mov     eax, dword ptr [esp+18H]                ; 002B _ 8B. 44 24, 18
        mov     dword ptr [esp+20H], edx                ; 002F _ 89. 54 24, 20
        mov     ebx, dword ptr [esp+20H]                ; 0033 _ 8B. 5C 24, 20
        mov     ecx, dword ptr [esp+14H]                ; 0037 _ 8B. 4C 24, 14
        mov     dword ptr [edx], eax                    ; 003B _ 89. 02
        mov     esi, dword ptr [ebx]                    ; 003D _ 8B. 33
        mov     eax, esi                                ; 003F _ 89. F0
        sar     eax, 31                                 ; 0041 _ C1. F8, 1F
        xor     esi, eax                                ; 0044 _ 33. F0
        sub     esi, eax                                ; 0046 _ 2B. F0
        mov     dword ptr [esp+1CH], 1                  ; 0048 _ C7. 44 24, 1C,
00000001
        cmp     ecx, 3                                  ; 0050 _ 83. F9, 03
        jz      ?_0056                                  ; 0053 _ 74, 24
        push    esi                                     ; 0055 _ 56
        mov     edx, offset FLAT:?_0001                 ; 0056 _ BA,
00000000(segrel)
        mov     ebx, 1                                  ; 005B _ BB, 00000001
        push    edx                                     ; 0060 _ 52
        push    ebx                                     ; 0061 _ 53
        push    dword ptr [esp+2CH]                     ; 0062 _ FF. 74 24, 2C
        push    dword ptr [esp+2CH]                     ; 0066 _ FF. 74 24, 2C
        call    _D3std5stdio21__T7writelnTiTAyaTAiZ7writelnFNfiAyaAiZv; 006A _
E8, 00000000(rel)
        mov     eax, 11                                 ; 006F _ B8, 0000000B
        call    _D11testmodule28__assertFiZv            ; 0074 _ E8,
00000000(rel)
?_0056: mov     ebx, dword ptr [esp+0CH]                ; 0079 _ 8B. 5C 24, 0C
        mov     esi, dword ptr [esp+10H]                ; 007D _ 8B. 74 24, 10
        add     esp, 36                                 ; 0081 _ 83. C4, 24
        xor     eax, eax                                ; 0084 _ 31. C0
        ret                                             ; 0086 _ C3
__Dmain ENDP
-----

Now the lines supposed to carry the "3" seem to be
-----
        mov     eax, 3                                  ; 0003 _ B8, 00000003
        mov     dword ptr [esp+18H], eax                ; 0015 _ 89. 44 24, 18
        mov     eax, dword ptr [esp+18H]                ; 002B _ 8B. 44 24, 18
        mov     dword ptr [edx], eax                    ; 003B _ 89. 02
-----
and then for some reason
-----
        mov     ecx, dword ptr [esp+14H]                ; 0037 _ 8B. 4C 24, 14
        cmp     ecx, 3                                  ; 0050 _ 83. F9, 03
        jz      ?_0056                                  ; 0053 _ 74, 24
-----

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