Intel® Architecture Instruction Set Extensions Programming Reference

INSTRUCTION SET REFERENCE - FMA
the infinite precision intermediate result, subtracts the odd single-precision floating-point elements and adds the
even single-precision floating-point values in the first source operand, performs rounding and stores the resulting
four or eight packed single-precision floating-point values to the destination operand (first source operand).
VEX.256 encoded version: The destination operand (also first source operand) is a YMM register and encoded in
reg_field. The second source operand is a YMM register and encoded in VEX.vvvv. The third source operand is a
YMM register or a 256-bit memory location and encoded in rm_field.
VEX.128 encoded version: The destination operand (also first source operand) is a XMM register and encoded in
reg_field. The second source operand is a XMM register and encoded in VEX.vvvv. The third source operand is a
XMM register or a 128-bit memory location and encoded in rm_field. The upper 128 bits of the YMM destination
register are zeroed.
Compiler tools may optionally support a complementary mnemonic for each instruction mnemonic listed in the
opcode/instruction column of the summary table. The behavior of the complementary mnemonic in situations
involving NANs are governed by the definition of the instruction mnemonic defined in the opcode/instruction
column. See also Section 2.3.1, “FMA Instruction Operand Order and Arithmetic Behavior”.
Operation
In the operations below, "+", "-", and "*" symbols represent addition, subtraction, and multiplication operations
with infinite precision inputs and outputs (no rounding).
VFMSUBADD132PS DEST, SRC2, SRC3
IF (VEX.128) THEN
MAXVL =2
ELSEIF (VEX.256)
MAXVL = 4
FI
For i = 0 to MAXVL -1{
n = 64*i;
DEST[n+31:n] RoundFPControl_MXCSR(DEST[n+31:n]*SRC3[n+31:n] + SRC2[n+31:n])
DEST[n+63:n+32] RoundFPControl_MXCSR(DEST[n+63:n+32]*SRC3[n+63:n+32] -SRC2[n+63:n+32])
}
IF (VEX.128) THEN
DEST[VLMAX-1:128] 0
FI
VFMSUBADD213PS DEST, SRC2, SRC3
IF (VEX.128) THEN
MAXVL =2
ELSEIF (VEX.256)
MAXVL = 4
FI
For i = 0 to MAXVL -1{
n = 64*i;
DEST[n+31:n] RoundFPControl_MXCSR(SRC2[n+31:n]*DEST[n+31:n] +SRC3[n+31:n])
DEST[n+63:n+32] RoundFPControl_MXCSR(SRC2[n+63:n+32]*DEST[n+63:n+32] -SRC3[n+63:n+32])
}
IF (VEX.128) THEN
DEST[VLMAX-1:128] 0
FI
VFMSUBADD231PS DEST, SRC2, SRC3
IF (VEX.128) THEN
MAXVL =2
ELSEIF (VEX.256)
MAXVL = 4
6-22 Ref. # 319433-014