The STM32 Cortex-M4 instruction set PM0214
158/262 PM0214 Rev 9
3.10.8 VFMA, VFMS
Floating-point Fused Multiply Accumulate and Subtract.
Syntax
VFMA{cond}.F32 {Sd,} Sn, Sm
VFMS{cond}.F32 {Sd,} Sn, Sm
Where:
• ‘cond’ is an optional condition code, see Conditional execution on page 65.
• ‘Sd’ is the destination register
• ‘Sn, Sm’ are the operand registers.
Operation
The VFMA instruction:
1. Multiplies the floating-point values in the operand registers.
2. Accumulates the results into the destination register.
3. The result of the multiply is not rounded before the accumulation.
The VFMS instruction:
1. Negates the first operand register.
2. Multiplies the floating-point values of the first and second operand registers.
3. Adds the products to the destination register.
4. Places the results in the destination register.
5. The result of the multiply is not rounded before the addition.
Restrictions
There are no restrictions.
Condition flags
These instructions do not change the flags.