diff options
Diffstat (limited to 'src/cuda-sim')
| -rw-r--r-- | src/cuda-sim/instructions.cc | 22 |
1 files changed, 16 insertions, 6 deletions
diff --git a/src/cuda-sim/instructions.cc b/src/cuda-sim/instructions.cc index 4c9392b..78d6450 100644 --- a/src/cuda-sim/instructions.cc +++ b/src/cuda-sim/instructions.cc @@ -3534,13 +3534,14 @@ void shfl_impl( const ptx_instruction *pI, core_t *core, warp_inst_t inst ) int bval = (thread->get_operand_value(src2, dst, i_type, thread, 1)).u32; int cval = (thread->get_operand_value(src3, dst, i_type, thread, 1)).u32; int mask = cval >> 8; + bval &= 0x1F; cval &= 0x1F; int maxLane = (lane & mask) | (cval & ~mask); int minLane = lane & mask; int src_idx; - int p; + unsigned p; switch(pI->shfl_op()) { case UP_OPTION: src_idx = lane - bval; @@ -3559,23 +3560,32 @@ void shfl_impl( const ptx_instruction *pI, core_t *core, warp_inst_t inst ) p = (src_idx <= maxLane); break; default: - printf("GPGPU-Sim PTX: ERROR: Unrecognized shfl option\n"); + printf("GPGPU-Sim PTX: ERROR: Invalid shfl option\n"); assert(0); break; } // copy from own lane if (!p) src_idx = lane; + // copy input from lane src_idx + ptx_thread_info *source = core->get_thread_info()[tid + src_idx]; ptx_reg_t data; if (inst.active(src_idx)) { - ptx_thread_info *source = core->get_thread_info()[tid + src_idx]; data = source->get_operand_value(src1, dst, i_type, source, 1); - } - if (i_type == PRED_TYPE) { - data.pred = p; + } else { + printf("GPGPU-Sim PTX: WARNING: shfl input value unpredictable for inactive threads in a warp\n"); + data.u32 = 0; } thread->set_operand_value(dst, data, i_type, thread, pI); + /* + TODO: deal with predicates appropriately using the following pseudocode: + if (!isGuardPredicateTrue(src_idx)) { + printf("GPGPU-Sim PTX: WARNING: shfl input value unpredictable for predicated-off threads in a warp\n"); + } + if (dest predicate selected) data.pred = p; + */ + // keep track of the number of threads that have executed in the warp warp_info->inc_done_threads(); if (warp_info->get_done_threads() == inst.active_count()) { |