............................Contents


1. The SunOS Assembler for x86	1
....1.1 References	2
2. Assembler Input	3
....2.1 Source Files in Assembly Language Format	4
.......File Organization	4
.......Statements	5
.......Values and Symbol Types	6
.......Expressions	8
.......Expression Syntax	8
.......Expression Semantics (Absolute vs. Relocatable)	10
.......Machine Instruction Syntax	11
.......Instruction Description	13
....2.2 Pseudo Operations	17
.......General Pseudo Operations	17
.......Symbol Definition Pseudo Operations	22


3. Instruction-Set Mapping	25
....3.1 Introduction	25
.......Notational Conventions	25
.......References	27
....3.2 Segment Register Instructions	27
....... Load Full Pointer (lds, les, lfs, lgs, and lss)	27
.......Pop Stack into Word (`pop`)	27
.......Push Stack into Word(`push`)	27
....3.3 I/O Instructions	28
.......Input from Port (in, ins)	28
.......Output from Port (out, outs)	28
....3.4 Flag Instructions	28
.......Load Flags into AH Register (lahf)	28
.......Store AH into Flags (sahf)	28
.......Pop Stack into Flag (`popf`)	28
.......Push Stack into Flag (`pushf`)	28
.......Complement Carry Flag (cmc)	28
.......Clear Carry Flag (clc)	29
.......Set Carry Flag (stc)	29
.......Clear Interrupt Flag (cli)	29
.......Set Interrupt Flag (sti)	29
.......Clear Direction Flag (cld)	29
.......Set Direction Flag (std)	29
....3.5 Arithmetic Logical Instructions	29


.......Integer Addition (add)	29
.......Integer Add With Carry (adc)	29
.......Integer Subtraction (sub)	30
.......Integer Subtraction With Borrow (sbb)	30
.......Compare Two Operands (cmp)	30
.......Increment by 1 (inc)	30
.......Decrease by 1 (dec)	30
.......Logical Comparison or Test (test)	30
.......Shift (sal, shl, sar, shr)	30
.......Double Precision Shift Left (shld)	31
.......Double Precision Shift Right (shrd)	31
.......One's Complement Negation (not)	31
.......Two's Complement Negation (neg)	31
.......Check Array Index Against Bounds (bound)	31
.......Logical And (and)	31
.......Logical Inclusive OR (or)	31
.......Logical Exclusion OR (xor)	32
....3.6 Multiply and Divide Instructions	32
.......Signed Multiply (imul)	32
.......Unsigned Multiplication of AL, AX or EAX(mul)	32
.......Unsigned Divide (div)	32
.......Signed Divide (idiv)	32
....3.7 Conversion Instructions	33
.......Convert Byte to Word (cbtw)	33


....... Convert Word to Long (cwtl)	33
.......Convert Signed Word to Signed Double Word (cwtd).	33
.......Convert Signed Long to Signed Double Long (cltd)	33
....3.8 Decimal Arithmetic Instructions	33
.......Decimal Adjust AL after Addition (daa)	33
.......Decimal Adjust AL after Subtraction (das)	33
.......ASCII Adjust after Addition (aaa)	33
.......ASCII Adjust after Subtraction (aas)	33
.......ASCII Adjust AX after Multiply (aam)	34
.......ASCII Adjust AX before Division (aad)	34
....3.9 Coprocessor Instructions	34
.......Wait (wait, fwait)	34
...3.10 String Instructions	34
.......Move Data from String to String (movs, smov)	34
.......Compare String Operands (cmps, scmp)	34
.......Store String Data (stos, ssto)	34
.......The Load String Operand (lods, slod)	34
.......Compare String Data (scas, ssca)	35
.......Look-Up Translation Table (xlat)	35
.......Repeat Following String Operation (rep, repnz, repz)	35
...3.11 Procedure Call and Return Instructions	35
.......Call Procedure (call)	35
.......Return from Procedure (ret)	35
.......Long Return (lret)	35


.......Enter or Make a Stack Frame for Procedure Parameters (en-
......ter)	35
.......High Level Procedure Exit (leave)	36
...3.12 Jump Instructions	36
.......Jump if ECX is Zero (jcxz)	36
.......Loop Control with CX Counter (loop, loopnz, loopz) .	36
.......Jump (jmp, ljmp)	36
...3.13 Interrupt Instructions	36
.......Call to Interrupt Procedure (int, into)	36
.......Interrupt Return (iret)	36
...3.14 Protection Model Instructions	37
.......Store Local Descriptor Table Register (sldt)	37
.......Store Task Register (str)	37
.......Load Local Descriptor Table Register (lldt)	37
.......Load Task Register (ltr)	37
.......Verify a Segment for Reading or Writing (verr, verw).	37
.......Store Global/Interrupt Descriptor Table Register (sgdt,
......sidt)	37
.......Load Global/Interrupt Descriptor Table (lgdt, lidt)	37
.......Store Machine Status Word (smsw)	37
.......Load Machine Status Word (lmsw)	38
.......Load Access Rights (lar)	38
.......Load Segment Limit (lsl)	38
.......Clear Task-Switched (clts)	38
.......Adjust RPL Field of Selector (arpl)	38


...3.15 Bit Instructions	38
.......Bit Scan Forward	38
.......Bit Scan Reverse	38
.......Bit Test	38
.......Bit Test And Complement	38
.......Bit Test And Reset	39
.......Bit Test And Set	39
...3.16 Exchange Instructions	39
.......Compare and Exchange [486]	39
...3.17 Floating Point Transcendental	39
.......Floating Point Sine	39
.......Floating Point Cosine	39
.......Floating Point Sine and Cosine	39
...3.18 Floating Point Constant	39
.......Floating Point Load One	39
...3.19 Processor Control Floating Point	40
.......Floating Point Load Control Word	40
.......Floating Point Load Environment	40
...3.20 Other Floating Point	40
.......Floating Point Different Reminder	40
...3.21 Floating Point Comparison	40
.......Floating Point Unsigned Compare	40
.......Floating Point Unsigned Compare And Pop	40
.......Floating Point Unsigned Compare And Pop Two	40


...3.22 Load and Move Instructions	41
.......Load Effective Address	41
.......Move	41
.......Move Segment Registers	41
.......Move Control Registers	41
.......Move Debug Registers	41
.......Move Test Registers	41
.......Move With Sign Extend	41
.......Move With Zero Extend	42
...3.23 Pop Instructions	42
.......Pop All General Registers	42
...3.24 Push Instructions	42
.......Push All General Registers	42
...3.25 Rotate Instructions	42
.......Rotate With Carry Left	42
.......Rotate With Carry Right	42
.......Rotate Left	42
.......Rotate Right	42
...3.26 Byte Instructions	43
.......Byte Set On Condition	43
.......Byte Swap [486]	43
...3.27 Exchange Instructions	43
.......Exchange And Add [486]	43
.......Exchange Register / Memory With Register	43


...3.28 Miscellaneous Instructions	43
.......Write Back and Invalidate Cache [486 only]	43
.......Invalidate [486 only]	43
.......Invalidate Page [486 only]	43
.......LOCK Prefix (lock)	44
.......No Operation (nop)	44
.......Halt (hlt)	44
...3.29 Real Transfers	44
.......Load real	44
.......Store real	44
.......Store real and pop	44
.......Exchange registers	44
...3.30 Integer Transfers	45
.......Integer load	45
.......Integer store	45
.......Integer store and pop	45
...3.31 Packed Decimal Transfers	45
.......Packed decimal (BCD) load	45
.......Packed decimal (BCD) store and pop	45
...3.32 Additions	45
.......Real add	45
.......Real add and pop	45
.......Integer add	45
...3.33 Subtractions	46


.......Subtract real and pop	46
.......Subtract real	46
.......Subtract real reversed	46
.......Subtract real reversed and pop	46
.......Integer subtract	46
.......Integer subtract reverse	46
...3.34 Multiplications	46
.......Multiply real	46
.......Multiply real and pop	46
.......Integer multiply	47
...3.35 Divisions	47
.......Divide real	47
.......Divide real and pop	47
.......Divide real reversed	47
.......Divide real reversed and pop	47
.......Integer divide	47
.......Integer divide reversed	47
...3.36 Floating Point Opcode Errors	47
...3.37 Other Arithmetic Operations	48
.......Square root	48
.......Scale	48
.......Partial remainder	48
.......Round to integer	48
.......Extract exponent and significand	49


.......Absolute value	49
.......Change sign	49
...3.38 Comparison Instructions	49
.......Compare real	49
.......Compare real and pop	49
.......Compare real and pop twice	49
.......Integer compare	49
.......Integer compare and pop	49
.......Test	49
.......Examine	50
...3.39 Transcendental Instructions	50
.......Partial tangent	50
.......Partial arctangent	50
........x 2 - 1	50
.......Y * log2 X	50
.......Y * log2 (X+1)	50
...3.40 Constant Instructions	50
.......Load log E	50 2
.......Load log 10	50 2
.......Load log 2	51 10
.......Load log 2	51 e
.......Load pi	51
.......Load + 0	51
...3.41 Processor Control Instructions	51


........Initialize processor	51
........No operation	51
........Save state	51
........Store control word	51
........Store environment	51
........Store status word	52
........Restore state	52
........Set protected mode	52
........CPU wait	52
........Clear exceptions	52
........Decrement stack pointer	52
........Free registers	52
........Increment stack pointer	52
4. Assembler Output	53
....4.1 Introduction to Assembler Output	53
....4.2 Object Files in Extensible and Linking Format (ELF)	54
........ELF Header	55
........Section Header	56
........Sections	61
........Relocation Tables	63
........Symbol Tables	64
........String Tables	66
A. Using the Assembler Command Line	67
....A.1 Assembler Command Line	67


...A.2 Assembler Command Line Options	68
...A.3 Disassembling Object Code	69
Index..........................................................................................	71