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## UMSUBL

Unsigned Multiply-Subtract Long multiplies two 32-bit register values, subtracts the product from a 64-bit register value, and writes the result to the 64-bit destination register.

This instruction is used by the alias UMNEGL.

 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 1 0 0 1 1 0 1 1 1 0 1 Rm 1 Ra Rn Rd U o0

#### 64-bit

UMSUBL <Xd>, <Wn>, <Wm>, <Xa>

```integer d = UInt(Rd);
integer n = UInt(Rn);
integer m = UInt(Rm);
integer a = UInt(Ra);
integer destsize = 64;
integer datasize = 32;
boolean sub_op = (o0 == '1');
boolean unsigned = (U == '1');```

### Assembler Symbols

 Is the 64-bit name of the general-purpose destination register, encoded in the "Rd" field.
 Is the 32-bit name of the first general-purpose source register holding the multiplicand, encoded in the "Rn" field.
 Is the 32-bit name of the second general-purpose source register holding the multiplier, encoded in the "Rm" field.
 Is the 64-bit name of the third general-purpose source register holding the minuend, encoded in the "Ra" field.

### Alias Conditions

AliasIs preferred when
UMNEGLRa == '11111'

### Operation

```bits(datasize) operand1 = X[n];
bits(datasize) operand2 = X[m];
bits(destsize) operand3 = X[a];

integer result;

if sub_op then
result = Int(operand3, unsigned) - (Int(operand1, unsigned) * Int(operand2, unsigned));
else
result = Int(operand3, unsigned) + (Int(operand1, unsigned) * Int(operand2, unsigned));

X[d] = result<63:0>;```

### Operational information

If PSTATE.DIT is 1:

• The execution time of this instruction is independent of:
• The values of the data supplied in any of its registers.
• The values of the NZCV flags.
• The response of this instruction to asynchronous exceptions does not vary based on:
• The values of the data supplied in any of its registers.
• The values of the NZCV flags.