[PATCH v2 1/2] powerpc/sstep: Add emulation support for ‘setb’ instruction
STALE1946d
LANDED
From: Sathvika Vasireddy <hidden>
Date: 2021-05-11 12:03:44
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
Landed in mainline as 5b75bd763d36 on 2021-05-23.
This adds emulation support for the following instruction: * Set Boolean (setb) Signed-off-by: Sathvika Vasireddy <redacted> --- arch/powerpc/lib/sstep.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+)
diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c
index 45bda2520755..aee42bcc775b 100644
--- a/arch/powerpc/lib/sstep.c
+++ b/arch/powerpc/lib/sstep.c@@ -1700,6 +1700,28 @@ int analyse_instr(struct instruction_op *op, const struct pt_regs *regs, op->val = regs->ccr & imm; goto compute_done; + case 128: /* setb */ + if (!cpu_has_feature(CPU_FTR_ARCH_300)) + goto unknown_opcode; + /* + * 'ra' encodes the CR field number (bfa) in the top 3 bits. + * Since each CR field is 4 bits, + * we can simply mask off the bottom two bits (bfa * 4) + * to yield the first bit in the CR field. + */ + ra = ra & ~0x3; + /* 'val' stores bits of the CR field (bfa) */ + val = regs->ccr >> (CR0_SHIFT - ra); + /* checks if the LT bit of CR field (bfa) is set */ + if (val & 8) + op->val = -1; + /* checks if the GT bit of CR field (bfa) is set */ + else if (val & 4) + op->val = 1; + else + op->val = 0; + goto compute_done; + case 144: /* mtcrf */ op->type = COMPUTE + SETCC; imm = 0xf0000000UL;
--
2.16.4