Renesas M32R-FPU Manual Do Utilizador
APPENDICES
APPENDICES-17
M32R-FPU Software Manual (Rev.1.01)
Appendix 4 Instruction Execution Time
Normally, the E stage is considered as representing as the instruction execution time,
however, because of the pipeline processing the execution time for other stages may
effect the total instruction execution time. In particular, the IF, D, and E stages of the
subsequent instruction must be considered after a branch has occurred.
The following shows the number of the instruction execution cycles for each pipeline
stage.
The execution time of the IF and MEM stages depends on the implementation of each
product of the M32R family.
Refer to the user's manual of each product for the execution time of these stages.
Note 1: FPU instruction uses E1 and EM stages.
Appendix Table 4.1.1 Instruction Execution Cycles per Pipeline Stage [excluding FPU instructions]
the number of execution cycles in each stage
instruction
IF
D
E
MEM1
MEM2
WB
load instruction (LD, LDB, LDUB, LDH, LDUH, LOCK)
R (note 1) 1
1
R (note 1)
1
1
store instruction (ST, STB, STH, UNLOCK)
R (note 1) 1
1
W (note 1)
1 (1) (note 2)
BSET, BCLR instructions
R (note 1) 1 R (note 1) W (note 1)
1
-
+3
multiply instruction (MUL)
R (note 1) 1
3
-
-
1
divide/reminder instruction (DIV, DIVU, REM, REMU)
R (note 1) 1
37
-
-
1
other instructions (DSP function instructions,
R (note 1) 1
1
-
-
1
including BTST, SETPSW, CLRPSW)
Note 1: R, W: Refer to the user's manual prepared for each product.
Note 2: Within the store instruction, only instructions which include the register indirect and
register update addressing mode require 1 cycle in the WB stage. All other instructions
do not require extra cycles.
Appendix Table 4.1.2 Instruction Execution Cycles per Pipeline Stage [FPU instructions]
the number of execution cycles in each stage
instruction
IF
D
E1
EM
EA
E2
WB
FMADD, FMSUB instructions
R (note 1) 1
-
1
1
1
1
FDIV instruction
R (note 1) 1
14
-
-
1
1
other FPU instructions
R (note 1) 1
1
-
-
1
1
Note 1: R, W: Refer to the user's manual prepared for each product.
APPENDIX 4
Appendix 4 Instruction Execution Time