From 0ccd55c011f72b5bb7d11a1f683e5ac949702417 Mon Sep 17 00:00:00 2001 From: Pavel Pisa Date: Mon, 18 Feb 2019 20:49:08 +0100 Subject: Report forward and stall for branches and add forward to execution phase. Signed-off-by: Pavel Pisa --- qtmips_machine/core.cpp | 10 +++++++++- qtmips_machine/core.h | 3 ++- 2 files changed, 11 insertions(+), 2 deletions(-) (limited to 'qtmips_machine') diff --git a/qtmips_machine/core.cpp b/qtmips_machine/core.cpp index e6f0971..a282807 100644 --- a/qtmips_machine/core.cpp +++ b/qtmips_machine/core.cpp @@ -370,7 +370,12 @@ struct Core::dtExecute Core::execute(const struct dtDecode &dt) { emit execute_alusrc_value(dt.alusrc); emit execute_regdest_value(dt.regd); emit execute_regw_num_value(dt.rwrite); - emit execute_stall_value(dt.stall); + if (dt.stall) + emit execute_stall_forward_value(1); + else if (dt.ff_rs != FORWARD_NONE || dt.ff_rt != FORWARD_NONE) + emit execute_stall_forward_value(2); + else + emit execute_stall_forward_value(0); return { .inst = dt.inst, @@ -612,6 +617,7 @@ CorePipelined::CorePipelined(Registers *regs, MemoryAccess *mem_program, MemoryA void CorePipelined::do_step(bool skip_break) { bool stall = false; + bool branch_stall = false; bool excpt_in_progress = false; std::uint32_t jump_branch_pc = dt_m.inst_addr; @@ -697,6 +703,7 @@ void CorePipelined::do_step(bool skip_break) { ((dt_d.bjr_req_rs && dt_d.inst.rs() == dt_e.rwrite) || (dt_d.bjr_req_rt && dt_d.inst.rt() == dt_e.rwrite))) { stall = true; + branch_stall = true; } else { if (hazard_unit != MachineConfig::HU_STALL_FORWARD || dt_m.memtoreg) { if (dt_m.rwrite != 0 && dt_m.regwrite && @@ -719,6 +726,7 @@ void CorePipelined::do_step(bool skip_break) { emit forward_m_d_rs_value(dt_d.forward_m_d_rs); emit forward_m_d_rt_value(dt_d.forward_m_d_rt); } + emit branch_forward_value((dt_d.forward_m_d_rs || dt_d.forward_m_d_rt)? 2: branch_stall); #if 0 if (stall) printf("STALL\n"); diff --git a/qtmips_machine/core.h b/qtmips_machine/core.h index 950fc0c..8140f61 100644 --- a/qtmips_machine/core.h +++ b/qtmips_machine/core.h @@ -136,7 +136,7 @@ signals: void execute_alusrc_value(std::uint32_t); void execute_regdest_value(std::uint32_t); void execute_regw_num_value(std::uint32_t); - void execute_stall_value(std::uint32_t); + void execute_stall_forward_value(std::uint32_t); void memory_inst_addr_value(std::uint32_t); void memory_alu_value(std::uint32_t); void memory_rt_value(std::uint32_t); @@ -153,6 +153,7 @@ signals: void writeback_regw_num_value(std::uint32_t); void hu_stall_value(std::uint32_t); + void branch_forward_value(std::uint32_t); void stop_on_exception_reached(); -- cgit v1.2.3