llvm-project

dd9d242b - [RISCV] Treat zext.h as a separate instruction from pack(w) with Zbkb. (#183364)

[RISCV] Treat zext.h as a separate instruction from pack(w) with Zbkb. (#183364) The Zbb encoding for zext.h is a subset of the encoding for pack(w). There is a statement in the ISA manual that says "For RV32, the pack instruction with rs2=x0 is the zext.h instruction. Hence, for RV32, any extension that contains the pack instruction also contains the zext.h instruction" This patch makes the zext.h instruction mnemonic canonical when only Zbkb is enabled. -Mno-aliases will not disable the printing of zext.h. I believe this matches binutils. I've taught the assembler to remap PACK/PACKW to ZEXT_H to make printing parsed assembly match the disassembler output.