[PATCH 3/6] powerpc sstep: Add cnttzw, cnttzd instruction emulation
From: Sandipan Das <hidden>
Date: 2018-09-03 15:20:01
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
This adds emulation support for the following integer instructions: * Count Trailing Zeros Word (cnttzw[.]) * Count Trailing Zeros Doubleword (cnttzd[.]) Signed-off-by: Sandipan Das <redacted> --- arch/powerpc/lib/sstep.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+)
diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c
index 18ac0a26c4fc..d57cb4e28621 100644
--- a/arch/powerpc/lib/sstep.c
+++ b/arch/powerpc/lib/sstep.c@@ -1816,6 +1816,20 @@ int analyse_instr(struct instruction_op *op, const struct pt_regs *regs, case 506: /* popcntd */ do_popcnt(regs, op, regs->gpr[rd], 64); goto logical_done_nocc; +#endif + case 538: /* cnttzw */ + if (!cpu_has_feature(CPU_FTR_ARCH_300)) + return -1; + val = (unsigned int) regs->gpr[rd]; + op->val = ( val ? __builtin_ctz(val) : 32 ); + goto logical_done; +#ifdef __powerpc64__ + case 570: /* cnttzd */ + if (!cpu_has_feature(CPU_FTR_ARCH_300)) + return -1; + val = regs->gpr[rd]; + op->val = ( val ? __builtin_ctzl(val) : 64 ); + goto logical_done; #endif case 922: /* extsh */ op->val = (signed short) regs->gpr[rd];
--
2.14.4