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<div class="moz-cite-prefix">Am 25.08.2020 um 23:47 schrieb Benito
van der Zander via fpc-pascal:<br>
</div>
<blockquote type="cite"
cite="mid:2f1e07ce-9180-535f-3e0d-6add2cd3cd91@benibela.de">
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<div id="smartTemplate4-template">Hi,</div>
<div><br>
</div>
<div>that is generating rather odd code (r40721)<br>
<p>project1.lpr:9 begin<br>
0000000000401090 55 push %rbp<br>
0000000000401091 4889e5 mov %rsp,%rbp<br>
0000000000401094 488d6424f0 lea
-0x10(%rsp),%rsp<br>
0000000000401099 48895df8 mov
%rbx,-0x8(%rbp)<br>
project1.lpr:10 if TypeInfo(T) =
TypeInfo(Integer) then WriteLn('an integer');<br>
000000000040109D 488d1584af0700 lea
0x7af84(%rip),%rdx # 0x47c028
<RTTI_$SYSTEM_$$_LONGINT><br>
00000000004010A4 488d057daf0700 lea
0x7af7d(%rip),%rax # 0x47c028
<RTTI_$SYSTEM_$$_LONGINT><br>
00000000004010AB 4839c2 cmp %rax,%rdx<br>
00000000004010AE 752b jne 0x4010db
<ADD$1$CRC713F463B+75><br>
00000000004010B0 e8cbcf0100 callq 0x41e080
<fpc_get_output><br>
00000000004010B5 4889c3 mov %rax,%rbx<br>
00000000004010B8 488d15412f0600 lea
0x62f41(%rip),%rdx # 0x464000 <_$PROJECT1$_Ld1><br>
00000000004010BF 4889de mov %rbx,%rsi<br>
00000000004010C2 31ff xor %edi,%edi<br>
00000000004010C4 e867d30100 callq 0x41e430
<fpc_write_text_shortstr><br>
00000000004010C9 e8d2700100 callq 0x4181a0
<fpc_iocheck><br>
00000000004010CE 4889df mov %rbx,%rdi<br>
00000000004010D1 e85ad20100 callq 0x41e330
<fpc_writeln_end><br>
00000000004010D6 e8c5700100 callq 0x4181a0
<fpc_iocheck><br>
project1.lpr:11 if TypeInfo(T) =
TypeInfo(String) then WriteLn('a string');<br>
00000000004010DB 488d0546af0700 lea
0x7af46(%rip),%rax # 0x47c028
<RTTI_$SYSTEM_$$_LONGINT><br>
00000000004010E2 488d1537b20700 lea
0x7b237(%rip),%rdx # 0x47c320
<RTTI_$SYSTEM_$$_SHORTSTRING><br>
00000000004010E9 4839d0 cmp %rdx,%rax<br>
00000000004010EC 752b jne 0x401119
<ADD$1$CRC713F463B+137><br>
00000000004010EE e88dcf0100 callq 0x41e080
<fpc_get_output><br>
00000000004010F3 4889c3 mov %rax,%rbx<br>
00000000004010F6 488d15132f0600 lea
0x62f13(%rip),%rdx # 0x464010 <_$PROJECT1$_Ld2><br>
00000000004010FD 4889de mov %rbx,%rsi<br>
0000000000401100 31ff xor %edi,%edi<br>
0000000000401102 e829d30100 callq 0x41e430
<fpc_write_text_shortstr><br>
0000000000401107 e894700100 callq 0x4181a0
<fpc_iocheck><br>
000000000040110C 4889df mov %rbx,%rdi<br>
000000000040110F e81cd20100 callq 0x41e330
<fpc_writeln_end><br>
0000000000401114 e887700100 callq 0x4181a0
<fpc_iocheck><br>
project1.lpr:12 end;<br>
<br>
</p>
The compiler should know everything about TypeInfo(T) and
optimize it away where possible<br>
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</blockquote>
<br>
For the compiler these are simply ordinary pointers, it does not
(yet) have any knowledge about "constant" pointers. Though there is
a bug report about that exact problem somewhere...<br>
<br>
Regards,<br>
Sven<br>
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