max

Maximum

This instruction is defined by:

Encoding

Synopsis

Returns the larger of two signed integers.

Software Hint

Calculating the absolute value of a signed integer can be performed using the following sequence: neg rD,rS followed by `max rD,rS,rD. When using this common sequence, it is suggested that they are scheduled with no intervening instructions so that implementations that are so optimized can fuse them together.

Access

M	HS	U	VS	VU
Always	Always	Always	Always	Always

Always

Decode Variables

Bits<5> xs2 = $encoding[24:20];
Bits<5> xs1 = $encoding[19:15];
Bits<5> xd = $encoding[11:7];

Execution

Pruned, XLEN == 64
Original

if (implemented?(ExtensionName::B) && (misa.B == 1'b0)) {
  raise(ExceptionCode::IllegalInstruction, mode(), $encoding);
}
X[xd] = ($signed(X[xs1]) > $signed(X[xs2])) ? X[xs1] : X[xs2];

if (implemented?(ExtensionName::B) && (misa.B == 1'b0)) {
  raise(ExceptionCode::IllegalInstruction, mode(), $encoding);
}
X[xd] = ($signed(X[xs1]) > $signed(X[xs2])) ? X[xs1] : X[xs2];

Exceptions

This instruction may result in the following synchronous exceptions:

IllegalInstruction