commit 1b5d0ab34c53d6e896d2c0958b1176e324bb7878

Author: Pedro Alves <palves@redhat.com>

Date:   Wed Jul 16 19:25:41 2014 +0100

    gdb.trace/tfile.c: Remove Thumb bit in one more more, general cleanup

    I noticed that the existing code casts a function's address to 'long',

    but that doesn't work correctly on some ABIs, like Win64, where long

    is 32-bit and while pointers are 64-bit:

      func_addr = (long) &write_basic_trace_file;

    Fixing that showed there's actually another place in the file that

    writes a function address to file, and therefore should clear the

    Thumb bit.  This commit adds a macro+function pair to centralize the

    Thumb bit handling, and uses it in both places.

    The rest is just enough changes to make the file build without

    warnings with "-Wall -Wextra" with x86_64-w64-mingw32-gcc and

    i686-w64-mingw32-gcc cross compilers, and with -m32/-m64 on x86_64

    GNU/Linux.  Currently with x86_64-w64-mingw32-gcc we get:

      $ x86_64-w64-mingw32-gcc tfile.c  -Wall -DTFILE_DIR=\"\"

      tfile.c: In function 'start_trace_file':

      tfile.c:51:23: error: 'S_IRGRP' undeclared (first use in this function)

    	 S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH);

    			 ^

      tfile.c:51:23: note: each undeclared identifier is reported only once for each function it appears in

      tfile.c:51:31: error: 'S_IROTH' undeclared (first use in this function)

    	 S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH);

    				 ^

      tfile.c: In function 'add_memory_block':

      tfile.c:79:10: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]

         ll_x = (unsigned long) addr;

    	    ^

      tfile.c: In function 'write_basic_trace_file':

      tfile.c:113:15: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]

         func_addr = (long) &write_basic_trace_file;

    		 ^

      tfile.c:137:3: warning: passing argument 1 of 'add_memory_block' from incompatible pointer type [enabled by default]

         add_memory_block (&testglob, sizeof (testglob));

         ^

      tfile.c:72:1: note: expected 'char *' but argument is of type 'int *'

       add_memory_block (char *addr, int size)

       ^

      tfile.c:139:3: warning: passing argument 1 of 'add_memory_block' from incompatible pointer type [enabled by default]

         add_memory_block (&testglob2, 1);

         ^

      tfile.c:72:1: note: expected 'char *' but argument is of type 'int *'

       add_memory_block (char *addr, int size)

       ^

      tfile.c: In function 'write_error_trace_file':

      tfile.c:185:3: warning: implicit declaration of function 'alloca' [-Wimplicit-function-declaration]

         char *hex = alloca (len * 2 + 1);

         ^

      tfile.c:185:15: warning: incompatible implicit declaration of built-in function 'alloca' [enabled by default]

         char *hex = alloca (len * 2 + 1);

    		 ^

      tfile.c:211:6: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]

    	(long) &write_basic_trace_file);

          ^

    Tested on x86_64 Fedora 20, -m64 and -m32.

    Tested by Yao on arm targets.

    gdb/testsuite/

    2014-07-16  Pedro Alves  <palves@redhat.com>

    	* gdb.trace/tfile.c: Include unistd.h and stdint.h.

    	(start_trace_file): Guard S_IRGRP and S_IROTH uses behind #ifdef.

    	(tfile_write_64, tfile_write_16, tfile_write_8, tfile_write_addr)

    	(tfile_write_buf): New functions.

    	(add_memory_block): Rewrite using the above.

    	(adjust_function_address): New function.

    	(FUNCTION_ADDRESS): New macro.

    	(write_basic_trace_file): Remove short_x local, and use

    	tfile_write_16. Change type of func_addr local to unsigned long

    	long.  Use FUNCTION_ADDRESS instead of handling the Thumb bit

    	here.  Cast argument of add_memory_block to char pointer.

    	(write_error_trace_file): Avoid alloca.  Use FUNCTION_ADDRESS.

    	(main): Remove parameters.

    	* gdb.trace/tfile.exp: Remove nowarnings.

Index: gdb-7.6.1/gdb/testsuite/gdb.trace/tfile.c

===================================================================

--- gdb-7.6.1.orig/gdb/testsuite/gdb.trace/tfile.c

+++ gdb-7.6.1/gdb/testsuite/gdb.trace/tfile.c

@@ -3,9 +3,11 @@

    GDB.  */

 #include <stdio.h>

+#include <unistd.h>

 #include <string.h>

 #include <fcntl.h>

 #include <sys/stat.h>

+#include <stdint.h>

 char spbuf[200];

@@ -23,9 +25,17 @@ int

 start_trace_file (char *filename)

 {

   int fd;

+  mode_t mode = S_IRUSR | S_IWUSR;

-  fd = open (filename, O_WRONLY|O_CREAT|O_APPEND,

-	     S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH);

+#ifdef S_IRGRP

+  mode |= S_IRGRP;

+#endif

+

+#ifdef S_IROTH

+  mode |= S_IROTH;

+#endif

+

+  fd = open (filename, O_WRONLY|O_CREAT|O_APPEND, mode);

   if (fd < 0)

     return fd;

@@ -44,31 +54,73 @@ finish_trace_file (int fd)

   close (fd);

 }

+static void

+tfile_write_64 (uint64_t value)

+{

+  memcpy (trptr, &value, sizeof (uint64_t));

+  trptr += sizeof (uint64_t);

+}

-void

-add_memory_block (char *addr, int size)

+static void

+tfile_write_16 (uint16_t value)

+{

+  memcpy (trptr, &value, sizeof (uint16_t));

+  trptr += sizeof (uint16_t);

+}

+

+static void

+tfile_write_8 (uint8_t value)

 {

-  short short_x;

-  unsigned long long ll_x;

+  memcpy (trptr, &value, sizeof (uint8_t));

+  trptr += sizeof (uint8_t);

+}

-  *((char *) trptr) = 'M';

-  trptr += 1;

-  ll_x = (unsigned long) addr;

-  memcpy (trptr, &ll_x, sizeof (unsigned long long));

-  trptr += sizeof (unsigned long long);

-  short_x = size;

-  memcpy (trptr, &short_x, 2);

-  trptr += 2;

+static void

+tfile_write_addr (char *addr)

+{

+  tfile_write_64 ((uint64_t) (uintptr_t) addr);

+}

+

+static void

+tfile_write_buf (const void *addr, size_t size)

+{

   memcpy (trptr, addr, size);

   trptr += size;

 }

 void

+add_memory_block (char *addr, int size)

+{

+  tfile_write_8 ('M');

+  tfile_write_addr (addr);

+  tfile_write_16 (size);

+  tfile_write_buf (addr, size);

+}

+

+/* Adjust a function's address to account for architectural

+   particularities.  */

+

+static uintptr_t

+adjust_function_address (uintptr_t func_addr)

+{

+#if defined(__thumb__) || defined(__thumb2__)

+  /* Although Thumb functions are two-byte aligned, function

+     pointers have the Thumb bit set.  Clear it.  */

+  return func_addr & ~1;

+#else

+  return func_addr;

+#endif

+}

+

+/* Get a function's address as an integer.  */

+

+#define FUNCTION_ADDRESS(FUN) adjust_function_address ((uintptr_t) &FUN)

+

+void

 write_basic_trace_file (void)

 {

   int fd, int_x;

-  short short_x;

-  long func_addr;

+  unsigned long long func_addr;

   fd = start_trace_file ("basic.tf");

@@ -86,15 +138,9 @@ write_basic_trace_file (void)

   /* Dump tracepoint definitions, in syntax similar to that used

      for reconnection uploads.  */

-  /* FIXME need a portable way to print function address in hex */

-  func_addr = (long) &write_basic_trace_file;

-#if defined(__thumb__) || defined(__thumb2__)

-  /* Although Thumb functions are two-byte aligned, function

-     pointers have the Thumb bit set.  Clear it.  */

-  func_addr &= ~1;

-#endif

+  func_addr = FUNCTION_ADDRESS (write_basic_trace_file);

-  snprintf (spbuf, sizeof spbuf, "tp T1:%lx:E:0:0\n", func_addr);

+  snprintf (spbuf, sizeof spbuf, "tp T1:%llx:E:0:0\n", func_addr);

   write (fd, spbuf, strlen (spbuf));

   /* (Note that we would only need actions defined if we wanted to

      test tdump.) */

@@ -106,14 +152,13 @@ write_basic_trace_file (void)

   /* (Encapsulate better if we're going to do lots of this; note that

      buffer endianness is the target program's enddianness.) */

   trptr = trbuf;

-  short_x = 1;

-  memcpy (trptr, &short_x, 2);

-  trptr += 2;

+  tfile_write_16 (1);

+

   tfsizeptr = trptr;

   trptr += 4;

-  add_memory_block (&testglob, sizeof (testglob));

+  add_memory_block ((char *) &testglob, sizeof (testglob));

   /* Divide a variable between two separate memory blocks.  */

-  add_memory_block (&testglob2, 1);

+  add_memory_block ((char *) &testglob2, 1);

   add_memory_block (((char*) &testglob2) + 1, sizeof (testglob2) - 1);

   /* Go back and patch in the frame size.  */

   int_x = trptr - tfsizeptr - sizeof (int);

@@ -158,8 +203,8 @@ write_error_trace_file (void)

 {

   int fd;

   const char made_up[] = "made-up error";

+  char hex[(sizeof (made_up) - 1) * 2 + 1];

   int len = sizeof (made_up) - 1;

-  char *hex = alloca (len * 2 + 1);

   fd = start_trace_file ("error.tf");

@@ -183,9 +228,8 @@ write_error_trace_file (void)

   /* Dump tracepoint definitions, in syntax similar to that used

      for reconnection uploads.  */

-  /* FIXME need a portable way to print function address in hex */

-  snprintf (spbuf, sizeof spbuf, "tp T1:%lx:E:0:0\n",

-	    (long) &write_basic_trace_file);

+  snprintf (spbuf, sizeof spbuf, "tp T1:%llx:E:0:0\n",

+	    (unsigned long long) FUNCTION_ADDRESS (write_basic_trace_file));

   write (fd, spbuf, strlen (spbuf));

   /* (Note that we would only need actions defined if we wanted to

      test tdump.) */

@@ -210,7 +254,7 @@ done_making_trace_files (void)

 }

 int

-main (int argc, char **argv, char **envp)

+main (void)

 {

   write_basic_trace_file ();

Index: gdb-7.6.1/gdb/testsuite/gdb.trace/tfile.exp

===================================================================

--- gdb-7.6.1.orig/gdb/testsuite/gdb.trace/tfile.exp

+++ gdb-7.6.1/gdb/testsuite/gdb.trace/tfile.exp

@@ -26,7 +26,7 @@ gdb_exit

 gdb_start

 standard_testfile

 if { [gdb_compile "$srcdir/$subdir/$srcfile" $binfile \

-	  executable {debug nowarnings}] != "" } {

+	  executable {debug}] != "" } {

     untested ${testfile}.exp

     return -1

 }