zext.h

Zero-extend halfword

This instruction is defined by:

Encoding

Synopsis

This instruction zero-extends the least-significant halfword of the source to XLEN by inserting 0’s into all of the bits more significant than 15.

The zext.h instruction is a pseudo-op for pack when Zbkb is implemented and XLEN == 32.

The zext.h instruction is a pseudo-op for packw when Zbkb is implemented and XLEN == 64.

Access

Always

Decode Variables

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] = X[rs1][15:0];

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] = X[rs1][15:0];

Exceptions

This instruction may result in the following synchronous exceptions:

IllegalInstruction