
TM1100 Preliminary Data Book
Philips Semiconductors
3-6
PRELIMINARY INFORMATION
File: arch.fm5, modified 7/23/99
3.2.3
Compute Operations
Compute operations are register-to-register operations.
The specified operation is performed on one or two
source registers and the result is written to the destina-
tion register.
Immediate Operations. Immediate operations load an
immediate constant (specified in the opcode) and pro-
duce a result in the destination register.
Floating-Point Compute Operations. Floating-point
compute operations are register-to-register operations.
The specified operation is performed on one or two
source registers and the result is written to the destina-
tion register. Unless otherwise mentioned all floating
point operations observe the rounding mode bits defined
in the PCSW register. All floating-point operations not
ending in “flags” update the PCSW exception flags. All
operations ending in “flags” compute the exception flags
as if the operation were executed and return the flag val-
ues (in the same format as in the PCSW); the exception
flags in the PCSW itself remain unchanged.
Multimedia Operations. These special compute opera-
tions are like normal compute operations, but the speci-
fied operations are not usually found in general purpose
CPU’s. These operations provide special support for
multi-media applications.
3.2.4
Special-Register Operations
Special register operations operate on the special regis-
ters: PCSW, DPC, SPC and CCCOUNT.
3.2.5
Control-Flow Operations
Control-flow operations change the value of the program
counter. Conditional jumps test the value in a register,
and based on this value, change the program counter to
the address contained in a second register or continue
execution with the next instruction. Unconditional jumps
always change the program counter to the specified im-
mediate address.
Control-flow operations can be interruptible or non-inter-
ruptible. The execution of an interruptible jump is the only
occasion where the TM1100 allows special event han-
3.3
TM1100 INSTRUCTION ISSUE RULES
The TM1100 VLIW CPU allows issue of 5 operations
each clock cycle according to a set of specific issue
rules. The issue rules impose issue time constraints and
a result writeback constraint. Any set of operations that
meets all constraints constitutes a legal TM1100 instruc-
tion. A more extensive description and a few special case
issue rules and limitations can be found in “Philips TriMe-
dia SDE Reference Manual, TM1100 Constraints”.
Issue time constraints:
an operation implies a need for a functional unit type
FALU
DSPMUL
FALU
DMEMSPEC
SHIFTER
FCOMP
DMEM
BRANCH
IFMUL
DSPALU
FTOUGH
(latency 17,
recovery 16)
DSPALU
ALU
CONST
issue slot 1
issue slot 2
issue slot 3
issue slot 4
issue slot 5
Figure 3-3. TM1100 issue slots, functional units and latency.