ASM ALIGN statement

Purpose | Identify an assembly-language statement. PowerBASIC's Inline Assembler supports 8086/8088, 80286, 80386, 80486, Pentium, Floating-Point, SIMD and MMX instructions.
Syntax | {! | ASM} {opcode | label} {! | ASM} ALIGN boundary
Remarks | This statement allows you to place assembly-language code within your PowerBASIC source code. An exclamation mark (!) serves as a shortcut for the ASM keyword. Each group of ASM statements must preserve the following CPU registers if the assembler code causes them to change: EBX, ESI, EDI, ESP, EBP, and all segment registers. See Saving Registers for more information. No other statements may appear on the same line as an ASM statement; however, comments are acceptable. ! DB 1, 2, 3, 4, 5 ! DD &H45001222, &HFFFF4327 Any variable referenced in an assembly-language statement must be defined prior to use. For example: x% = 10 ! MOV AX, x% You cannot access the target of a pointer with a single ASM statement as you might do in BASIC source code. Instead, you must use the pointer address indirectly. To simulate the BASIC statement INCR @x, you would write: DIM x AS INTEGER PTR ASM MOV EAX, x ; EAX holds a pointer to an Integer ASM INC WORD PTR [EAX] ; Add one to target value String literals of up to four characters may be used in Inline Assembler code: ! MOV AL, "a" ; move char a into reg AL ! MOV AX, "ab" ; move chars ab into reg AX ! ; "a" into AL, "b" into AH ! MOV EAX, "abcd" ; move chars abcd into reg EAX PowerBASIC recognizes either an apostrophe ( ' ) or a semi-colon ( ; ) to specify a comment after a line of assembler code: ! PUSH EAX ; save the EAX register ! PUSH EBX ' save the EBX register
ALIGN | ASM ALIGN is used in critical situations to gain maximum efficiency from assembler code sections. ASM ALIGN is used to round up the instruction location to a power of two address. The boundary parameter shown must be a power of two, in the range of 2 through 256. PowerBASIC inserts NOP instructions into the code section to bring the instruction location up to the desired address. If the instruction location is already at a multiple of boundary, ALIGN has no effect. The #ALIGN metastatement functions in the same respect as ASM ALIGN, but the ASM ALIGN statement is more suited to being used in a PREFIX/END PREFIX block.
Restrictions | Care should be exercised to ensure registers are appropriately preserved when Inline Assembler code is intermixed with BASIC statements. See Saving Registers for more information.
See also | The Inline Assembler, ASMDATA
Example | To add the values a&, b&, and c&, you would write: LOCAL a&, b&, c&, z& ! MOV EAX, a& ! ADD EAX, b& ! ADD EAX, c& ! MOV z&, EAX
Notes | The follow lists outline the supported mnemonics, data types, operators, and registers that can be used with the ASM statement.
The ASM statement supports the following mnemonics:
AAA, AAD, AAM, AAS, ADC, ADD, ADDPD, ADDPS, ADDSD, ADDSS, ADDSUBPD, ADDSUBPS, ANDNPD, ANDNPS, ANDPD, ANDPS, AND BLENDPD, BLENDPS, BLENDVPD, BLENDVPS, BOUND, BSF, BSR, BSWAP, BT, BTC, BTR, BTS CALL, CBW, CWD, CDQ, CLC, CLD, CLFLUSH, CLI, CMC, CMOVA, CMOVAE, CMOVB, CMOVBE, CMOVC, CMOVE, CMOVG, CMOVGE, CMOVL, CMOVLE, CMOVNA, CMOVNAE, CMOVNB, CMOVNBE, CMOVNC, CMOVNE, CMOVNG, CMOVNGE, CMOVNL, CMOVNLE, CMOVNO, CMOVNP, CMOVNS, CMOVNZ, CMOVO, CMOVP, CMOVPE, CMOVPO, CMOVS, CMOVZ, CMP, CMPPD, CMPPS, CMPSB, CMPSD, CMPSS, CMPSW, CMPXCHG, CMPXCHG8B, COMISD, COMISS, CPUID, CRC32, CVTDQ2PD, CVTDQ2PS, CVTPD2DQ, CVTPD2PI, CVTPD2PS, CVTPI2PD, CVTPI2PS, CVTPS2DQ, CVTPS2PD, CVTPS2PI, CVTSD2SI, CVTSD2SS, CVTSI2SD, CVTSI2SS, CVTSS2SD, CVTSS2SI, CVTTPD2DQ, CVTTPD2PI, CVTTPS2DQ, CVTTPS2PI, CVTTSD2SI, CVTTSS2SI, CWDE DAA, DAS, DEC, DIV, DIVPD, DIVPS, DIVSD, DIVSS, DPPD, DPPS EMMS, ENTER, EXTRACTPS F2XM1, FABS, FADD, FADDP, FBLD, FBSTP, FCHS, FCLEX, FCMOVB, FCMOVBE, FCMOVE, FCMOVNB, FCMOVNBE, FCMOVNE, FCMOVNU, FCMOVU, FCOM, FCOMI, FCOMIP, FCOMP, FCOMPP, FCOS, FDECSTP, FDIV, FDIVP, FDIVR, FDIVRP, FFREE, FIADD, FICOM, FICOMP, FIDIV, FIDIVR, FILD, FIMUL, FINCSTP, FINIT, FIST, FISTP, FISTTP, FISUB, FISUBR, FLD, FLD1, FLDCW, FLDENV, FLDL2E, FLDL2T, FLDLG2, FLDLN2, FLDPI, FLDZ, FMUL, FMULP, FNCLEX, FNINIT, FNLDCW, FNOP, FNSAVE, FNSTCW, FNSTENV, FNSTSW, FPATAN, FPREM, FPREM1, FPTAN, FRNDINT, FRSTOR, FSAVE, FSCALE, FSIN, FSINCOS, FSQRT, FST, FSTCW, FSTENV, FSTP, FSTSW, FSUB, FSUBP, FSUBR, FSUBRP, FTST, FUCOM, FUCOMI, FUCOMIP, FUCOMP, FUCOMPP, FWAIT, FXAM, FXCH, FXRSTOR, FXSAVE, FXTRACT, FYL2X, FYL2XP1 HADDPD, HADDPS, HLT, HSUBPD, HSUBPS IDIV, IMUL, IN, INC, INSB, INSD, INSERTPS, INSW, INT, INTO, IRET, IRETD JA, JAE, JB, JBE, JC, JE, JECXZ, JG, JGE, JL, JLE, JMP, JNA, JNAE, JNB, JNBE, JNC, JNE, JNG, JNGE, JNL, JNLE, JNO, JNP, JNS, JNZ, JO, JP, JPE, JPO, JS, JZ LAHF, LAR, LDDQU, LDMXCSR, LDS, LEA, LEAVE, LES, LFENCE, LFS, LGS, LOCK, LODSB, LODSD, LODSW, LOOP, LOOPE, LOOPNE, LOOPNZ, LOOPZ, LSL, LSS MASKMOVDQU, MASKMOVQ, MAXPD, MAXPS, MAXSD, MAXSS, MFENCE, MINPD, MINPS, MINSD, MINSS, MONITOR, MOV, MOVAPD, MOVAPS, MOVD, MOVDDUP, MOVDQA, MOVDQU, MOVDQ2Q, MOVHLPS, MOVHPD, MOVHPS, MOVLHPS, MOVLPD, MOVLPS, MOVMSKPD, MOVMSKPS, MOVNTDQA, MOVNTDQ, MOVNTI, MOVNTPD, MOVNTPS, MOVNTQ, MOVQ2DQ, MOVQ, MOVSB, MOVSD, MOVSHDUP, MOVSLDUP, MOVSS, MOVSW, MOVSX, MOVUPD, MOVUPS, MOVZX, MPSADBW, MUL, MULPD, MULPS, MULSD, MULSS, MWAIT NEG, NOP, NOT OR, ORPD, ORPS, OUT, OUTSB, OUTSD, OUTSW PABSB, PABSD, PABSW, PACKSSDW, PACKSSWB, PACKUSDW, PACKUSWB, PADDB, PADDD, PADDQ, PADDSB, PADDSW, PADDUSB, PADDUSW, PADDW, PALIGNR, PAND, PANDN, PAUSE, PAVGB, PAVGW, PBLENDVB, PBLENDW, PCMPEQB, PCMPEQD, PCMPEQW, PCMPEQQ, PCMPESTRI, PCMPESTRM, PCMPISTRI, PCMPISTRM, PCMPGTB, PCMPGTD, PCMPGTQ, PCMPGTW, PEXTRB, PEXTRD, PEXTRW, PHADDD, PHADDW, PHADDSW, PHMINPOSUW, PHSUBD, PHSUBSW, PHSUBW, PINSRB, PINSRD, PINSRW, PMADDUBSW, PMADDWD, PMAXSB, PMAXSD, PMAXSW, PMAXUB, PMAXUD, PMAXUW, PMINSB, PMINSD, PMINSW, PMINUB, PMINUD, PMINUW, PMOVMSKB, PMOVSXBW, PMOVSXBD, PMOVSXBQ, PMOVSXWD, PMOVSXWQ, PMOVSXDQ, PMOVZXBW, PMOVZXBD, PMOVZXBQ, PMOVZXWD, PMOVZXWQ, PMOVZXDQ, PMULDQ, PMULHRSW, PMULHUW, PMULHW, PMULLD, PMULLW, PMULUDQ, POP, POPA, POPAD, POPCNT, POPF, POPFD, POR, PREFETCHT0, PREFETCHT1, PREFETCHT2, PREFETCHNTA, PSADBW, PSHUFB, PSHUFD, PSHUFHW, PSHUFLW, PSHUFW, PSIGNB, PSIGND, PSIGNW, PSLLD, PSLLDQ, PSLLQ, PSLLW, PSRAD, PSRAW, PSRLD, PSRLDQ, PSRLD, PSRLQ, PSRLW, PSUBB, PSUBD, PSUBQ, PSUBW, PSUBSB, PSUBSW, PSUBUSB, PSUBUSW, PTEST, PUNPCKHBW, PUNPCKHDQ, PUNPCKHQDQ, PUNPCKHWD, PUNPCKLBW, PUNPCKLDQ, PUNPCKLQDQ, PUNPCKLWD, PUSH, PUSHA, PUSHAD, PUSHF, PUSHFD, PXOR RCL, RCR, RCPPS, RCPSS, RDPMC, RDTSC, REP, REPE, REPNE, REPNZ, REPZ, RET, RETF, RETN, ROL, ROR, ROUNDPD, ROUNDPS, ROUNDSD, ROUNDSS, RSQRTPS, RSQRTSS SAHF, SAL, SAR, SBB, SCASB, SCASD, SCASW, SETA, SETAE, SETB, SETBE, SETC, SETE, SETG, SETGE, SETL, SETLE, SETNA, SETNAE, SETNB, SETNBE, SETNC, SETNE, SETNG, SETNGE, SETNL, SETNLE, SETNO, SETNP, SETNS, SETNZ, SETO, SETP, SETPE, SETPO, SETS, SETZ, SFENCE, SHL, SHLD, SHR, SHRD, SHUFPD. SHUFPS, SQRTPD, SQRTPS, SQRTSD, SQRTSS, STC, STD, STI, STMXCSR, STOSB, STOSD, STOSW, SUB, SUBPD, SUBPS, SUBSD, SUBSS TEST UCOMISD, UCOMISS, UNPCKHPD, UNPCKHPS, UNPCKLPD, UNPCKLPS VERR, VERW WAIT XADD, XCHG, XGETBV, XLAT, XOR, XORPD, XORPS, XRSTOR, XSAVE, XSETBV
The ASM statement supports the following data types and operators:
BYTE DB, DD, DW, DWD, DWORD FAR NEAR POINTER, PTR QWD, QWORD SHORT TBY, TBYTE WORD, WRD
The ASM statement supports the following registers:
Integer
32-bit | Low 16-bit | High 8-bit | Low 8-bit
EAX | AX | AH | AL
EBX | BX | BH | BL
ECX | CX | CH | CL
EDX | DX | DH | DL
ESI | SI |  |
EDI | DI |  |
ESP | SP |  |
EBP | BP |  |
Segments CS, DS, ES, SS, FS, GS MMX Registers MM(0), MM(1), MM(2), MM(3), MM(4), MM(5), MM(6), MM(7) MM0, MM1, MM2, MM3, MM4, MM5, MM6, MM7 Floating Point registers ST(0), ST(1), ST(2), ST(3), ST(4), ST(5), ST(6), ST(7) XMM registers XMM(0), XMM(1), XMM(2), XMM(3), XMM(4), XMM(5), XMM(6), XMM(7) XMM0, XMM1, XMM2, XMM3, XMM4, XMM5, XMM6, XMM7 ASM supports these special words PowerBASIC supports three special reserved words, which are used to specify a return value from a procedure of the same type:
FUNCTION | ASM mov FUNCTION, eax
METHOD | ASM mov METHOD, 3
PROPERTY | ASM mov PROPERTY, dx
The above examples are the functional equivalent of the comparable BASIC syntax: FUNCTION = x& METHOD = 3 PROPERTY = z% The exception is that the assembler syntax allows you to assign a return value directly from an appropriate CPU register. Of course, these special reserved words may only be referenced within a procedure of the same type (FUNCTION may only be used in a user-defined function, etc.)
See Also | #ALIGN, ASMDATA/END ASMDATA