ARM Compiler toolchain v4.1 for µVision Using the Assembler: Pre-UAL VFP mnemonics

Pre-UAL VFP mnemonics

Where UAL mnemonics use .F32 to specify single-precision data, pre-UAL mnemonics use S appended to the instruction mnemonic. For example, VABS.F32 was FABSS.

Where UAL mnemonics use .F64 to specify double-precision data, pre-UAL mnemonics use D appended to the instruction mnemonic. For example, VCMPE.F64 was FCMPED.

Table 36 shows the pre-UAL mnemonics of those instructions that are affected by VFP vector mode. All other VFP instructions are always scalar regardless of the settings of LEN and STRIDE.

Table 36. Pre-UAL VFP mnemonics

UAL mnemonic	Equivalent pre-UAL mnemonic
`VABS`	`FABS`
`VADD`	`FADD`
`VDIV`	`FDIV`
`VMLA`	`FMAC`
`VMLS`	`FNMAC`
`VMOV` (immediate)	`FCONST` ^[a]
`VMOV` (register)	`FCPY`
`VMUL`	`FMUL`
`VNEG`	`FNEG`
`VNMLA`	`FNMSC`
`VNMLS`	`FMSC`
`VNMUL`	`FNMUL`
`VSQRT`	`FSQRT`
`VSUB`	`FSUB`
^[a]The immediate in `VMOV` (immediate) is the floating-point number you want to load. The immediate in `FCONST` is the number encoded in the instruction to produce the floating-point number you want to load. See Immediate values in FCONST for details.

Immediate values in FCONST

Table 37 shows the floating-point values you can load using FCONST. Trailing zeroes are omitted for clarity. The immediate value you must put in the FCONST instruction is the decimal representation of the binary number abcdefgh, where:

a: is 0 for positive numbers, or 1 for negative numbers
bcd: is shown in the column headings
efgh: is shown in the row headings.

Alternatively, you can use 0x followed by the hexadecimal representation.

Table 37. Floating-point values for use with FCONST

	000	001	010	011	100	101	110	111
efgh
0000	2.0	4.0	8.0	16.0	0.125	0.25	0.5	1.0
0001	2.125	4.25	8.5	17.0	0.1328125	0.265625	0.53125	1.0625
0010	2.25	4.5	9.0	18.0	0.140625	0.28125	0.5625	1.125
0011	2.375	4.75	9.5	19.0	0.1484375	0.296875	0.59375	1.1875
0100	2.5	5.0	10.0	20.0	0.15625	0.3125	0.625	1.25
0101	2.625	5.25	10.5	21.0	0.1640625	0.328125	0.65625	1.3125
0110	2.75	5.5	11.0	22.0	0.171875	0.34375	0.6875	1.375
0111	2.875	5.75	11.5	23.0	0.1796875	0.359375	0.71875	1.4375
1000	3.0	6.0	12.0	24.0	0.1875	0.375	0.75	1.5
1001	3.125	6.25	12.5	25.0	0.1953125	0.390625	0.78125	1.5625
1010	3.25	6.5	13.0	26.0	0.203125	0.40625	0.8125	1.625
1011	3.375	6.75	13.5	27.0	0.2109375	0.421875	0.84375	1.6875
1100	3.5	7.0	14.0	28.0	0.21875	0.4375	0.875	1.75
1101	3.625	7.25	14.5	29.0	0.2265625	0.453125	0.90625	1.8125
1110	3.75	7.5	15.0	30.0	0.234375	0.46875	0.9375	1.875
1111	3.875	7.75	15.5	31.0	0.2421875	0.484375	0.96875	1.9375

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