translate-all: include guest address in out_asm output

We already have information about where each guest instructions
representation starts stored in the tcg_ctx->gen_insn_data so we can
rectify the PC for faults. We can re-use this information to annotate
the out_asm output with guest instruction address which makes it a bit
easier to work out where you are especially with longer blocks. A
minor wrinkle is that some instructions get optimised away so we have
to scan forward until we find some actual generated code.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>

Message-Id: <20200513175134.19619-11-alex.bennee@linaro.org>

accel/tcg/translate-all.c

@@ -1794,14 +1794,43 @@ TranslationBlock *tb_gen_code(CPUState *cpu,
     if (qemu_loglevel_mask(CPU_LOG_TB_OUT_ASM) &&
         qemu_log_in_addr_range(tb->pc)) {
         FILE *logfile = qemu_log_lock();
+        int code_size, data_size = 0;
+        g_autoptr(GString) note = g_string_new("[tb header & initial instruction]");
+        size_t chunk_start = 0;
+        int insn = 0;
         qemu_log("OUT: [size=%d]\n", gen_code_size);
         if (tcg_ctx->data_gen_ptr) {
-            size_t code_size = tcg_ctx->data_gen_ptr - tb->tc.ptr;
-            size_t data_size = gen_code_size - code_size;
-            size_t i;
+            code_size = tcg_ctx->data_gen_ptr - tb->tc.ptr;
+            data_size = gen_code_size - code_size;
+        } else {
+            code_size = gen_code_size;
+        }
 
-            log_disas(tb->tc.ptr, code_size, NULL);
+        /* Dump header and the first instruction */
+        chunk_start = tcg_ctx->gen_insn_end_off[insn];
+        log_disas(tb->tc.ptr, chunk_start, note->str);
 
+        /*
+         * Dump each instruction chunk, wrapping up empty chunks into
+         * the next instruction. The whole array is offset so the
+         * first entry is the beginning of the 2nd instruction.
+         */
+        while (insn <= tb->icount && chunk_start < code_size) {
+            size_t chunk_end = tcg_ctx->gen_insn_end_off[insn];
+            if (chunk_end > chunk_start) {
+                g_string_printf(note, "[guest addr: " TARGET_FMT_lx "]",
+                                tcg_ctx->gen_insn_data[insn][0]);
+                log_disas(tb->tc.ptr + chunk_start, chunk_end - chunk_start,
+                          note->str);
+                chunk_start = chunk_end;
+            }
+            insn++;
+        }
+
+        /* Finally dump any data we may have after the block */
+        if (data_size) {
+            int i;
+            qemu_log("  data: [size=%d]\n", data_size);
             for (i = 0; i < data_size; i += sizeof(tcg_target_ulong)) {
                 if (sizeof(tcg_target_ulong) == 8) {
                     qemu_log("0x%08" PRIxPTR ":  .quad  0x%016" PRIx64 "\n",
@@ -1813,8 +1842,6 @@ TranslationBlock *tb_gen_code(CPUState *cpu,
                              *(uint32_t *)(tcg_ctx->data_gen_ptr + i));
                 }
             }
-        } else {
-            log_disas(tb->tc.ptr, gen_code_size, NULL);
         }
         qemu_log("\n");
         qemu_log_flush();