E3: operating the memory. Write the data into the memory.
Branch Instructions
Instructions
Units of Instruction
16
Conditional Operations
执行条件寄存器判断。
17
A0/A1/A2 B0/B1/B2 为0（Z=0）时才执行；或者不为0（Z = 1）是才执行。 Creg 3bit决定对哪个寄存器进行判断。
Operations
1. Src ? dst : 32 bit data
2. Src_h:Src_l ? dst_h:dst_l : 40 bit data. H is 8msb 3. src_o:Src_e ? dst_o:dst_e : 64 bit data o is 32 msb
Instruction description Description format
EXAMPLE (.unit) src, dst .unit = .L1, .L2, .S1, .S2, .D1, .D2
src and dst indicate source and destination, respectively. The (.unit) dictates which functional unit the instruction is mapped to (.L1, .L2, .S1, .S2, .M1, .M2, .D1, or .D2).
可见，DSP的汇编已经制定命令执行的Unit了，dispatch动作仅仅是根据指令进行分发而已。 指令格式有以下特点：
1. 在同一个指令中，使用不同的unit，与操作数的bit数什么的都有关系。所以从指令使
用的unit，可以看到很多关于操作数的性质。 2. 指令中已经包含了指令的unit，所以dispatch动作仅仅是根据指令进行分发 3.
ABS
ABS Absolute Value With Saturation
Syntax ABS (.unit) src2, dst //for 32bit data
or
ABS (.unit) src2_h:src2_l, dst_h:dst_l //for 40bit data unit = .L1 or .L2
Instruction Type Single-cycle Delay Slots 0 Compatibility C62x, C64x, and C64x+ CPU Examples Example 1
ABS .L1 A1,A5
Examples Example 2
ABS .L1 A1:A0,A5:A4
18
x cross path for src2; 0 = do not use cross path, 1 = use cross path op opfield; field within opcode that specifies a unique instruction： 指令号
p parallel execution; 0 = next instruction is not executed in parallel, 1 = next instruction is executed in parallel
s side A or B for destination; 0 = side A, 1 = side B.
ABS2 （for 16bit）
ABS2 Absolute Value With Saturation, Signed, Packed 16-Bit
Syntax ABS2 (.unit) src2, dst
unit = .L1 or .L2
Instruction Type Single-cycle Delay Slots 0 Compatibility C64x and C64x+ CPU
Src2：是两个独立的16bit的数据。 Dst：是两个独立的16bit的数据。
ADD系列（ADD/ADDAB/ADDKPC）
ADD
ADD Add Two Signed Integers Without Saturation
Syntax ADD (.unit) src1, src2, dst
or
ADD (.L1 or .L2) src1, src2_h:src2_l, dst_h:dst_l or
ADD (.D1 or .D2) src2, src1, dst (if the cross path form is not used) or
ADD (.D1 or .D2) src1, src2, dst (if the cross path form is used) or
ADD (.D1 or .D2) src2, src1, dst (if the cross path form is used with a constant) unit = .D1, .D2, .L1, .L2, .S1, .S2
Instruction Type Single-cycle Delay Slots 0
19
Compatibility C62x, C64x, and C64x+ CPU
Execution:
Src1 + Src2 --> dst
ADDAB
ADDAB Add Using Byte Addressing Mode
Syntax ADDAB (.unit) src2, src1, dst (C64x and C64x+ CPU)
or
ADDAB (.unit) B14/B15, ucst15, dst (C64x+ CPU) unit = .D1 or .D2
Compatibility C62x, C64x, and C64x+ CPU
sint Signed 32-bit integer value
ucstn n-bit unsigned constant field (for example, ucst5)
Execution:
src2 + src1 → dst
ADDK
Syntax ADDK (.unit) cst, dst
20