max

Maximum

This instruction is defined by:

Encoding

Synopsis

This instruction 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

Always

Decode Variables

Bits<5> rs2 = $encoding[24:20];
Bits<5> rs1 = $encoding[19:15];
Bits<5> rd = $encoding[11:7];

Execution

Pruned, XLEN == 64
Original

if ((%%LINK%csr_field;misa.B;CSR[misa].B%% == 1'b0)) {
  %%LINK%func;raise;raise%%(ExceptionCode::IllegalInstruction, %%LINK%func;mode;mode%%(), $encoding);
}
X[rd] = ($signed(X[rs1]) > $signed(X[rs2])) ? X[rs1] : X[rs2];

if (%%LINK%func;implemented?;implemented?%%(ExtensionName::B) && (%%LINK%csr_field;misa.B;CSR[misa].B%% == 1'b0)) {
  %%LINK%func;raise;raise%%(ExceptionCode::IllegalInstruction, %%LINK%func;mode;mode%%(), $encoding);
}
X[rd] = ($signed(X[rs1]) > $signed(X[rs2])) ? X[rs1] : X[rs2];

Exceptions

This instruction may result in the following synchronous exceptions:

IllegalInstruction