[GDBJIT] Show x64pc in gdb, also added documentation (#2163)

* [GDBJIT] Show x64pc in gdb

* Add env. variable and documentation

* typo

* oops

docs/USAGE.md

@@ -239,6 +239,11 @@ Behavior with FillBlock is not available (FillBlock build Dynarec blocks and is
 * 0 : Dynarec will not wait for FillBlock to ready and use Interpreter instead (might speedup a bit massive multithread or JIT programs)
 * 1 : Dynarec will wait for FillBlock to be ready (Default)
 
+#### BOX64_DYNAREC_GDBJIT *
+The GDBJIT debugging support, only available with the compilation option GDBJIT=ON, enable it with gdb command: jit-reader-load /usr/local/lib/libbox64gdbjitreader.so.
+* 0 : Dynarec will not generate GDBJIT debuginfo. (Default)
+* 1 : Dynarec will generate GDBJIT debuginfo.
+
 #### BOX64_DYNAREC_MISSING *
 Dynarec print the missing opcodes
 * 0 : not print the missing opcode (Default, unless DYNAREC_LOG>=1 or DYNAREC_DUMP>=1 is used)

docs/box64.pod

@@ -367,6 +367,13 @@ Behavior with FillBlock is not available (FillBlock build Dynarec blocks and is
     * 0 : Dynarec will not wait for FillBlock to ready and use Interpreter instead (might speedup a bit massive multithread or JIT programs)
     * 1 : Dynarec will wait for FillBlock to be ready (Default)
 
+=item B<BOX64_DYNAREC_GDBJIT>=I<0|1>
+
+The GDBJIT debugging support, only available with the compilation option GDBJIT=ON, enable it with gdb command: jit-reader-load /usr/local/lib/libbox64gdbjitreader.so.
+
+    * 0 : Dynarec will not generate GDBJIT debuginfo. (Default)
+    * 1 : Dynarec will generate GDBJIT debuginfo.
+
 =item B<BOX64_SSE_FLUSHTO0>=I<0|1>
 
 Handling of SSE Flush to 0 flags

gdbjit/reader.c

@@ -1,4 +1,7 @@
 #include "gdbjit.h"
+#include <stdio.h>
+
+static char block_name_buffer[16];
 
 static enum gdb_status read_debug_info(struct gdb_reader_funcs* self, struct gdb_symbol_callbacks* cbs, void* memory, long memory_sz)
 {
@@ -6,7 +9,8 @@ static enum gdb_status read_debug_info(struct gdb_reader_funcs* self, struct gdb
 
     struct gdb_object* object = cbs->object_open(cbs);
     struct gdb_symtab* symtab = cbs->symtab_open(cbs, object, block->filename);
-    cbs->block_open(cbs, symtab, NULL, block->start, block->end, "(block)");
+    sprintf(block_name_buffer, "%x", block->x64start);
+    cbs->block_open(cbs, symtab, NULL, block->start, block->end, block_name_buffer);
 
     cbs->line_mapping_add(cbs, symtab, block->nlines, block->lines);
 

src/core.c

@@ -72,7 +72,6 @@ int box64_rdtsc_1ghz = 0;
 uint8_t box64_rdtsc_shift = 0;
 char* box64_insert_args = NULL;
 char* box64_new_args = NULL;
-int box64_dynarec_gdbjit = 1;
 #ifdef DYNAREC
 int box64_dynarec = 1;
 int box64_dynarec_dump = 0;
@@ -98,6 +97,7 @@ uintptr_t box64_nodynarec_start = 0;
 uintptr_t box64_nodynarec_end = 0;
 uintptr_t box64_dynarec_test_start = 0;
 uintptr_t box64_dynarec_test_end = 0;
+int box64_dynarec_gdbjit = 0;
 #ifdef ARM64
 int arm64_asimd = 0;
 int arm64_aes = 0;
@@ -901,6 +901,15 @@ void LoadLogEnv()
         if(!box64_dynarec_wait)
             printf_log(LOG_INFO, "Dynarec will not wait for FillBlock to ready and use Interpreter instead\n");
     }
+    p = getenv("BOX64_DYNAREC_GDBJIT");
+    if(p) {
+        if(strlen(p)==1) {
+            if(p[0]>='0' && p[0]<='1')
+                box64_dynarec_gdbjit = p[0]-'0';
+        }
+        if(box64_dynarec_gdbjit)
+            printf_log(LOG_INFO, "Dynarec will generate debuginfo for gdbjit\n");
+    }
     p = getenv("BOX64_DYNAREC_ALIGNED_ATOMICS");
     if(p) {
         if(strlen(p)==1) {

src/dynarec/dynarec_native.c

@@ -754,7 +754,7 @@ void* FillBlock64(dynablock_t* block, uintptr_t addr, int alternate, int is32bit
         dynarec_log(LOG_NONE, "%s\n", (box64_dynarec_dump>1)?"\e[m":"");
     }
     if (box64_dynarec_gdbjit) {
-        GdbJITNewBlock(helper.gdbjit_block, (GDB_CORE_ADDR)block->actual_block, (GDB_CORE_ADDR)block->actual_block + native_size);
+        GdbJITNewBlock(helper.gdbjit_block, (GDB_CORE_ADDR)block->actual_block, (GDB_CORE_ADDR)block->actual_block + native_size, helper.start);
     }
     int oldtable64size = helper.table64size;
     size_t oldnativesize = helper.native_size;

src/include/gdbjit.h

@@ -11,19 +11,20 @@ typedef struct gdbjit_block_s {
     FILE* file;
     GDB_CORE_ADDR start;
     GDB_CORE_ADDR end;
-    uintptr_t alloced;
+    uintptr_t x64start;
+    size_t alloced;
     size_t nlines;
     struct gdb_line_mapping lines[0];
 } gdbjit_block_t;
 
 
-void GdbJITNewBlock(gdbjit_block_t* block, GDB_CORE_ADDR start, GDB_CORE_ADDR end);
+void GdbJITNewBlock(gdbjit_block_t* block, GDB_CORE_ADDR start, GDB_CORE_ADDR end, uintptr_t x64start);
 gdbjit_block_t* GdbJITBlockAddLine(gdbjit_block_t* block, GDB_CORE_ADDR addr, const char* line);
 void GdbJITBlockReady(gdbjit_block_t* block);
 
 #else
 
-#define GdbJITNewBlock(a, b, c)
+#define GdbJITNewBlock(a, b, c, d)
 #define GdbJITBlockAddLine(a, b, c) NULL
 #define GdbJITBlockReady(a)
 

src/tools/gdbjit.c

@@ -46,7 +46,7 @@ gdbjit_descriptor_t __jit_debug_descriptor = { 1, GDBJIT_NOACTION, NULL, NULL };
 
 /* --------------------------------------------------------------------------- */
 
-void GdbJITNewBlock(gdbjit_block_t* block, GDB_CORE_ADDR start, GDB_CORE_ADDR end)
+void GdbJITNewBlock(gdbjit_block_t* block, GDB_CORE_ADDR start, GDB_CORE_ADDR end, uintptr_t x64start)
 {
     if (!block)
         return;
@@ -59,6 +59,7 @@ void GdbJITNewBlock(gdbjit_block_t* block, GDB_CORE_ADDR start, GDB_CORE_ADDR en
 
     block->start = start;
     block->end = end;
+    block->x64start = x64start;
     block->alloced = block->nlines = 0;
 }