zext.h

Zero-extend halfword

This instruction is defined by:

Encoding

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.

Always

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

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

if (implemented?(ExtensionName::B) && (CSR[misa].B == 1'b0)) {
  raise(ExceptionCode::IllegalInstruction, mode(), $encoding);
}
X[rd] = X[rs1][15:0];