From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-0.9 required=5.0 tests=BAYES_00,FORGED_GMAIL_RCVD, FREEMAIL_FROM autolearn=no autolearn_force=no version=3.4.4 X-Google-Thread: 103376,e0fd0b6258908ca5 X-Google-NewGroupId: yes X-Google-Attributes: gida07f3367d7,domainid0,public,usenet X-Google-Language: ENGLISH,ASCII-7-bit Received: by 10.68.219.170 with SMTP id pp10mr21503235pbc.1.1341845842071; Mon, 09 Jul 2012 07:57:22 -0700 (PDT) Path: l9ni11215pbj.0!nntp.google.com!news1.google.com!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail From: theanalogmachine@gmail.com Newsgroups: comp.lang.ada Subject: Re: Help with Inline assembly Date: Mon, 9 Jul 2012 07:43:56 -0700 (PDT) Organization: http://groups.google.com Message-ID: <024cf9df-ad12-4476-a14d-eb99def28b77@googlegroups.com> References: <85b57cc7-352e-4cee-a161-b0aaf1665305@googlegroups.com> NNTP-Posting-Host: 76.20.243.45 Mime-Version: 1.0 X-Trace: posting.google.com 1341845841 20585 127.0.0.1 (9 Jul 2012 14:57:21 GMT) X-Complaints-To: groups-abuse@google.com NNTP-Posting-Date: Mon, 9 Jul 2012 14:57:21 +0000 (UTC) In-Reply-To: Complaints-To: groups-abuse@google.com Injection-Info: glegroupsg2000goo.googlegroups.com; posting-host=76.20.243.45; posting-account=JqutYwoAAAC8IGXNQJ34VIRLaJ4LKhwz User-Agent: G2/1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Date: 2012-07-09T07:43:56-07:00 List-Id: I now have the program executing, and potentially functioning -- I won't kn= ow for sure until I test it with some sort of emulator that simulates older= processors. Here is the fixed code for anyone interested (this came in han= dy too http://x86asm.net/articles/what-i-dislike-about-gas/) ----------------------- -- Can_Execute_CPUID -- ----------------------- function Can_Execute_CPUID return Boolean is Result : Unsigned_32 :=3D 0; begin Asm( -------------------------------------------------------- " begin: " & Ascii.LF & Ascii.HT & " pushfl " & Ascii.LF & Ascii.HT & " popl %%eax " & Ascii.LF & Ascii.HT &=20 " test $0x00200000, %%eax " & Ascii.LF & Ascii.HT & " jz set21 " & Ascii.LF & Ascii.HT & " and $0xffdfffff, %%eax " & Ascii.LF & Ascii.HT & " pushl %%eax " & Ascii.LF & Ascii.HT & " popfl " & Ascii.LF & Ascii.HT & " pushfl " & Ascii.LF & Ascii.HT &=20 " popl %%eax " & Ascii.LF & Ascii.HT &=20 " test $0x00200000, %%eax " & Ascii.LF & Ascii.HT & " jz good " & Ascii.LF & Ascii.HT &=20 " jmp error " & Ascii.LF & Ascii.HT & -------------------------------------------------------- " set21: " & Ascii.LF & Ascii.HT &=20 " or $0x00200000, %%eax " & Ascii.LF & Ascii.HT & " pushl %%eax " & Ascii.LF & Ascii.HT & " popfl " & Ascii.LF & Ascii.HT & " pushfl " & Ascii.LF & Ascii.HT &=20 " popl %%eax " & Ascii.LF & Ascii.HT &=20 " test $0x00200000, %%eax " & Ascii.LF & Ascii.HT & " jnz good " & Ascii.LF & Ascii.HT &=20 " jmp error " & Ascii.LF & Ascii.HT & =20 -------------------------------------------------------- " error: " & Ascii.LF & Ascii.HT &=20 " movl $0x0, %%eax " & Ascii.LF & Ascii.HT &=20 " jmp end " & Ascii.LF & Ascii.HT & -------------------------------------------------------- " good: " & Ascii.LF & Ascii.HT &=20 " movl $0x1, %%eax " & Ascii.LF & Ascii.HT & -------------------------------------------------------- " end: " & Ascii.LF & Ascii.HT ,=20 -------------------------------------------------------- Outputs =3D> Unsigned_32'Asm_Output("=3Da", Result), Volatile =3D> True); if Result /=3D 1 then return True; end if; return False; end Can_Execute_CPUID; On Monday, July 9, 2012 4:41:23 AM UTC-4, (unknown) wrote: > Thanks for the reply, it seems your suggestion did not fix my primary pro= blem (that a EXCEPTION_ACCESS_VIOLATION is displayed at runtime). Could you= elaborate more on your suggestion? >=20 > On Sunday, July 8, 2012 11:53:05 PM UTC-4, Jim C. wrote: > > I am running into problems translating Intel style visual C inline asse= mbly to something gnat can understand (http://gcc.gnu.org/onlinedocs/gnat_u= gn_unw/Inline-Assembler.html#Inline-Assembler). The goal of the program is = to test for the existence of the CPUID command which only exists after the = 386. > >=20 > > The program as it stands compiles without any errors, but it will fail = at runtime with the following printed: "raised PROGRAM_ERROR : EXCEPTION_AC= CESS_VIOLATION" -- I can't tell if I am violating syntax or something more = complicated is involved. > >=20 > > ///////////////////////////////////// Visual C code > > static bool HasCPUID( void ) { > > __asm=20 > > { > > pushfd // save eflags > > pop eax > > test eax, 0x00200000 // check ID bit > > jz set21 // bit 21 is not set, so jump to set_21 > > and eax, 0xffdfffff // clear bit 21 > > push eax // save new value in register > > popfd // store new value in flags > > pushfd > > pop eax > > test eax, 0x00200000 // check ID bit > > jz good > > jmp err // cpuid not supported > > set21: > > or eax, 0x00200000 // set ID bit > > push eax // store new value > > popfd // store new value in EFLAGS > > pushfd > > pop eax > > test eax, 0x00200000 // if bit 21 is on > > jnz good > > jmp err > > } > > err: > > return false; > > good: > > return true; > > } > >=20 > > --------------------------------------- Ada code > > with > > Ada.Text_IO, > > Interfaces, > > System.Machine_Code; > > use > > Ada.Text_IO, > > Interfaces, > > System.Machine_Code; > > procedure Assembly_Test > > is > > C : Character :=3D Ascii.Nul; > > Result : Unsigned_32 :=3D 0; > > begin > > Asm( > > ------------------------------------------------------- > > " pushf " & Ascii.LF & Ascii.HT & > > " pop %%eax " & Ascii.LF & Ascii.HT &=20 > > " test %%eax, 0x00200000 " & Ascii.LF & Ascii.HT & > > " jz set21 " & Ascii.LF & Ascii.HT & > > " and %%eax, 0xffdfffff " & Ascii.LF & Ascii.HT & > > " push %%eax " & Ascii.LF & Ascii.HT & > > " popf " & Ascii.LF & Ascii.HT & > > " pushf " & Ascii.LF & Ascii.HT &=20 > > " pop %%eax " & Ascii.LF & Ascii.HT &=20 > > " test %%eax, 0x00200000 " & Ascii.LF & Ascii.HT & > > " jz good " & Ascii.LF & Ascii.HT &=20 > > " jmp err " & Ascii.LF & Ascii.HT & > > ------------------------------------------------------- > > " set21: " & Ascii.LF & Ascii.HT &=20 > > " or %%eax, 0x00200000 " & Ascii.LF & Ascii.HT & > > " push %%eax " & Ascii.LF & Ascii.HT & > > " popf " & Ascii.LF & Ascii.HT & > > " pushf " & Ascii.LF & Ascii.HT &=20 > > " pop %%eax " & Ascii.LF & Ascii.HT &=20 > > " test %%eax, 0x00200000 " & Ascii.LF & Ascii.HT & > > " jnz good " & Ascii.LF & Ascii.HT &=20 > > " jmp err " & Ascii.LF & Ascii.HT & =20 > > ------------------------------------------------------- > > " err: " & Ascii.LF & Ascii.HT &=20 > > " mov 0x0, %%eax " & Ascii.LF & Ascii.HT &=20 > > ------------------------------------------------------- > > " good: " & Ascii.LF & Ascii.HT &=20 > > " mov 0x1, %%eax " & Ascii.LF & Ascii.HT ,=20 > > ------------------------------------------------------- > > Outputs =3D> Unsigned_32'Asm_Output("=3Da", Result), > > Volatile =3D> True); > > if Result /=3D 1 then > > Put_Line("False"); > > end if; > > Put_Line("True"); > > Get(C); > > end Assembly_Test;