Remove already-implemented TODO.

[riscv-isa-sim.git] / riscv / execute.cc

diff --git a/riscv/execute.cc b/riscv/execute.cc
index ae4c9597a1bd00af5b9ecfd992c470c807659d66..e2e72d69ef244fdd79836b2bbddd60af3017feee 100644 (file)
--- a/riscv/execute.cc
+++ b/riscv/execute.cc
@@ -54,16 +54,17 @@ static reg_t execute_insn(processor_t* p, reg_t pc, insn_fetch_t fetch)
 // fetch/decode/execute loop
 void processor_t::step(size_t n)
 {
-  // TODO: get_interrupt() isn't super fast. Does that matter?
-  if (state.dcsr.cause == DCSR_CAUSE_NONE &&
-      sim->debug_module.get_interrupt(id)) {
-    enter_debug_mode(DCSR_CAUSE_DEBUGINT);
-  }
-
-  if (state.dcsr.cause != DCSR_CAUSE_NONE) {
-    // In Debug Mode, just do 10 steps at a time. Otherwise we're going to be
+  if (state.dcsr.cause == DCSR_CAUSE_NONE) {
+    // TODO: get_interrupt() isn't super fast. Does that matter?
+    if (sim->debug_module.get_interrupt(id)) {
+      enter_debug_mode(DCSR_CAUSE_DEBUGINT);
+    } else if (state.dcsr.halt) {
+      enter_debug_mode(DCSR_CAUSE_HALT);
+    }
+  } else {
+    // In Debug Mode, just do 11 steps at a time. Otherwise we're going to be
     // spinning the rest of the time anyway.
-    n = std::max(n, (size_t) 10);
+    n = std::min(n, (size_t) 11);
   }
 
   while (n > 0) {
@@ -89,12 +90,22 @@ void processor_t::step(size_t n)
     {
       take_interrupt();
 
-      if (unlikely(debug))
+      // When we might single step, use the slow loop instead of the fast one.
+      if (unlikely(debug || state.single_step != state.STEP_NONE || state.dcsr.cause))
       {
         while (instret < n)
         {
+          if (unlikely(state.single_step == state.STEP_STEPPING)) {
+            state.single_step = state.STEP_STEPPED;
+          } else if (unlikely(state.single_step == state.STEP_STEPPED)) {
+            state.single_step = state.STEP_NONE;
+            enter_debug_mode(DCSR_CAUSE_STEP);
+            // enter_debug_mode changed state.pc, so we can't just continue.
+            break;
+          }
+
           insn_fetch_t fetch = mmu->load_insn(pc);
-          if (!state.serialized)
+          if (debug && !state.serialized)
             disasm(fetch.insn);
           pc = execute_insn(this, pc, fetch);
           advance_pc();