c.jalr

Jump and Link Register.

This instruction is defined by:

Encoding

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Synopsis

C.JALR (jump and link register) performs the same operation as C.JR, but additionally writes the address of the instruction following the jump (pc+2) to the link register, x1. C.JALR expands to jalr x1, 0(rs1).

Access

M

HS

U

VS

VU

Always

Always

Always

Always

Always

Decode Variables

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

Execution

  • Pruned, XLEN == 64

  • Original

if ((%%LINK%csr_field;misa.C;CSR[misa].C%% == 1'b0)) {
  %%LINK%func;raise;raise%%(ExceptionCode::IllegalInstruction, %%LINK%func;mode;mode%%(), $encoding);
}
XReg returnaddr;
returnaddr = $pc + 2;
%%LINK%func;jump;jump%%(X[rs1]);
X[1] = returnaddr;
if (%%LINK%func;implemented?;implemented?%%(ExtensionName::C) && (%%LINK%csr_field;misa.C;CSR[misa].C%% == 1'b0)) {
  %%LINK%func;raise;raise%%(ExceptionCode::IllegalInstruction, %%LINK%func;mode;mode%%(), $encoding);
}
XReg returnaddr;
returnaddr = $pc + 2;
%%LINK%func;jump;jump%%(X[rs1]);
X[1] = returnaddr;

Exceptions

This instruction may result in the following synchronous exceptions:

  • IllegalInstruction

  • InstructionAddressMisaligned