Abstract: The present invention relates to a pipeline microprocessor (MP) comprising a first pipeline stage (ST1) comprising means IPC, MMU, PC, B2, DEC1) for reading and decoding instructions (CODEOP, ADRs, ADRd) of a program recorded in a memory (MEM), and a second pipeline stage (ST2), contiguous to the first pipeline stage, comprising two sectors (ST21, ST22) activated one after the other during complementary half-cycles of a clock signal (H1) of the microprocessor. The first sector reads data contained in two registers (Rd, Rs) of a bank of registers (BANK1, BANK2) of the microprocessor and carries out an operation on the data according to an instruction (CODEOP, ADRs, ADRd) received at the previous clock cycle. The second sector (ST22) comprises means (B4, DEC1) to record the result of the operation in a register of the bank of registers (BANK1, BANK2). Application especially to chip cards.

Abstract: The invention relates to a microprocessor (MP) comprising means to decode (DEC1) a compact instruction (BMV) for the concatenation of at least one bit (bi) of a first binary word (W1) with at least one bit of a second binary word (W2), and means (REGBANK, MUX, BSHIFT) to process this instruction in one clock cycle. Advantages: fast processing of a concatenation operation. Application especially to chip cards.