YJIT: Avoid undercounting retired_in_yjit (#8038)

* YJIT: Count the number of failed instructions

* Rename yjit_insns_count to exec_instructions instead

* Hoist out the exec_instruction counter

doc/yjit/yjit.md

@@ -226,7 +226,6 @@ irb(main):001:0> RubyVM::YJIT.runtime_stats
 Some of the counters include:
 
 :exec_instruction - how many Ruby bytecode instructions have been executed
-:yjit_insns_count - how many Ruby bytecode instruction have been executed in compiled code
 :binding_allocations - number of bindings allocated
 :binding_set - number of variables set via a binding
 :code_gc_count - number of garbage collections of compiled code since process start

yjit.rb

@@ -317,7 +317,7 @@ module RubyVM::YJIT
       out.puts "total_exit_count:      " + format_number(13, stats[:total_exit_count])
       out.puts "total_insns_count:     " + format_number(13, stats[:total_insns_count])
       out.puts "vm_insns_count:        " + format_number(13, stats[:vm_insns_count])
-      out.puts "yjit_insns_count:      " + format_number(13, stats[:exec_instruction])
+      out.puts "exec_instruction:      " + format_number(13, stats[:exec_instruction])
       out.puts "ratio_in_yjit:         " + ("%12.1f" % stats[:ratio_in_yjit]) + "%"
       out.puts "avg_len_in_yjit:       " + ("%13.1f" % stats[:avg_len_in_yjit])
 

yjit/src/codegen.rs

@@ -847,14 +847,14 @@ pub fn gen_single_block(
             verify_ctx(&jit, &asm.ctx);
         }
 
+        // :count-placement:
+        // Count bytecode instructions that execute in generated code.
+        // Note that the increment happens even when the output takes side exit.
+        gen_counter_incr(&mut asm, Counter::exec_instruction);
+
         // Lookup the codegen function for this instruction
         let mut status = None;
         if let Some(gen_fn) = get_gen_fn(VALUE(opcode)) {
-            // :count-placement:
-            // Count bytecode instructions that execute in generated code.
-            // Note that the increment happens even when the output takes side exit.
-            gen_counter_incr(&mut asm, Counter::exec_instruction);
-
             // Add a comment for the name of the YARV instruction
             asm.comment(&format!("Insn: {:04} {} (stack_size: {})", insn_idx, insn_name(opcode), asm.ctx.get_stack_size()));