Philipp Tomsich 54c1760937 target/riscv: Fix orc.b implementation ... The earlier implementation fell into a corner case for bytes that were 0x01, giving a wrong result (but not affecting our application test cases for strings, as an ASCII value 0x01 is rare in those...). This changes the algorithm to: 1. Mask out the high-bit of each bytes (so that each byte is <= 127). 2. Add 127 to each byte (i.e. if the low 7 bits are not 0, this will overflow into the highest bit of each byte). 3. Bitwise-or the original value back in (to cover those cases where the source byte was exactly 128) to saturate the high-bit. 4. Shift-and-mask (implemented as a mask-and-shift) to extract the MSB of each byte into its LSB. 5. Multiply with 0xff to fan out the LSB to all bits of each byte. Fixes: d7a4fcb034 ("target/riscv: Add orc.b instruction for Zbb, removing gorc/gorci") Signed-off-by: Philipp Tomsich <philipp.tomsich@vrull.eu> Reported-by: Vincent Palatin <vpalatin@rivosinc.com> Tested-by: Vincent Palatin <vpalatin@rivosinc.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-id: 20211013184125.2010897-1-philipp.tomsich@vrull.eu Signed-off-by: Alistair Francis <alistair.francis@wdc.com>		2021-10-22 07:47:51 +10:00
..
trans_privileged.c.inc	target/riscv: Remove exit_tb and lookup_and_goto_ptr	2021-10-15 16:39:14 -07:00
trans_rva.c.inc	target/riscv: Use {get,dest}_gpr for RVA	2021-09-01 11:59:12 +10:00
trans_rvb.c.inc	target/riscv: Fix orc.b implementation	2021-10-22 07:47:51 +10:00
trans_rvd.c.inc	target/riscv: Use {get,dest}_gpr for RVD	2021-09-01 11:59:12 +10:00
trans_rvf.c.inc	target/riscv: Use {get,dest}_gpr for RVF	2021-09-01 11:59:12 +10:00
trans_rvh.c.inc	target/riscv: Tidy trans_rvh.c.inc	2021-09-01 11:59:12 +10:00
trans_rvi.c.inc	target/riscv: Remove exit_tb and lookup_and_goto_ptr	2021-10-15 16:39:14 -07:00
trans_rvm.c.inc	target/riscv: Move gen_* helpers for RVM	2021-09-01 11:59:12 +10:00
trans_rvv.c.inc	target/riscv: Pass the same value to oprsz and maxsz for vmv.v.v	2021-10-22 07:47:51 +10:00