PATCH: Support "ah", "bh", "ch", "dh" in amd64

["H.J. Lu" <hongjiu.lu@intel.com>]

Hi,

AMD64 can access "ah", "bh", "ch", "dh".  I missed them in my x86
pseudo register support.  This patch adds them. OK to install?

Thanks.


H.J.
---
gdb/

2010-03-03  H.J. Lu  <hongjiu.lu@intel.com>

	* amd64-tdep.c (amd64_byte_names): Add "ah", "bh", "ch", "dh".
	(amd64_pseudo_register_read): Handle "ah", "bh", "ch", "dh".
	(amd64_pseudo_register_write): Likewise.
	(amd64_init_abi): Set num_byte_regs to 20.

gdb/testsuite/

2010-03-03  H.J. Lu  <hongjiu.lu@intel.com>

	* gdb.arch/amd64-byte.exp: Check "ah", "bh", "ch", "dh".

diff --git a/gdb/amd64-tdep.c b/gdb/amd64-tdep.c
index 8c41a8a..ee2b5a6 100644
--- a/gdb/amd64-tdep.c
+++ b/gdb/amd64-tdep.c
@@ -215,7 +215,8 @@ amd64_arch_reg_to_regnum (int reg)
 static const char *amd64_byte_names[] =
 {
   "al", "bl", "cl", "dl", "sil", "dil", "bpl", "spl",
-  "r8l", "r9l", "r10l", "r11l", "r12l", "r13l", "r14l", "r15l"
+  "r8l", "r9l", "r10l", "r11l", "r12l", "r13l", "r14l", "r15l",
+  "ah", "bh", "ch", "dh"
 };
 
 /* Register names for word pseudo-registers.  */
@@ -263,8 +264,17 @@ amd64_pseudo_register_read (struct gdbarch *gdbarch,
       int gpnum = regnum - tdep->al_regnum;
 
       /* Extract (always little endian).  */
-      regcache_raw_read (regcache, gpnum, raw_buf);
-      memcpy (buf, raw_buf, 1);
+      if (gpnum >= 16)
+	{
+	  /* Special handling for AH, BH, CH, DH.  */
+	  regcache_raw_read (regcache, gpnum - 16, raw_buf);
+	  memcpy (buf, raw_buf + 1, 1);
+	}
+      else
+	{
+	  regcache_raw_read (regcache, gpnum, raw_buf);
+	  memcpy (buf, raw_buf, 1);
+	}
     }
   else if (i386_dword_regnum_p (gdbarch, regnum))
     {
@@ -289,12 +299,24 @@ amd64_pseudo_register_write (struct gdbarch *gdbarch,
     {
       int gpnum = regnum - tdep->al_regnum;
 
-      /* Read ...  */
-      regcache_raw_read (regcache, gpnum, raw_buf);
-      /* ... Modify ... (always little endian).  */
-      memcpy (raw_buf, buf, 1);
-      /* ... Write.  */
-      regcache_raw_write (regcache, gpnum, raw_buf);
+      if (gpnum >= 16)
+	{
+	  /* Read ... AH, BH, CH, DH.  */
+	  regcache_raw_read (regcache, gpnum - 16, raw_buf);
+	  /* ... Modify ... (always little endian).  */
+	  memcpy (raw_buf + 1, buf, 1);
+	  /* ... Write.  */
+	  regcache_raw_write (regcache, gpnum - 16, raw_buf);
+	}
+      else
+	{
+	  /* Read ...  */
+	  regcache_raw_read (regcache, gpnum, raw_buf);
+	  /* ... Modify ... (always little endian).  */
+	  memcpy (raw_buf, buf, 1);
+	  /* ... Write.  */
+	  regcache_raw_write (regcache, gpnum, raw_buf);
+	}
     }
   else if (i386_dword_regnum_p (gdbarch, regnum))
     {
@@ -2228,7 +2250,7 @@ amd64_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
   tdep->num_core_regs = AMD64_NUM_GREGS + I387_NUM_REGS;
   tdep->register_names = amd64_register_names;
 
-  tdep->num_byte_regs = 16;
+  tdep->num_byte_regs = 20;
   tdep->num_word_regs = 16;
   tdep->num_dword_regs = 16;
   /* Avoid wiring in the MMX registers for now.  */
diff --git a/gdb/testsuite/gdb.arch/amd64-byte.exp b/gdb/testsuite/gdb.arch/amd64-byte.exp
index 9a14099..c76876b 100644
--- a/gdb/testsuite/gdb.arch/amd64-byte.exp
+++ b/gdb/testsuite/gdb.arch/amd64-byte.exp
@@ -52,7 +52,6 @@ if ![runto_main] then {
     gdb_suppress_tests
 }
 
-set nr_regs 14
 set byte_regs(1) al
 set byte_regs(2) bl
 set byte_regs(3) cl
@@ -67,6 +66,10 @@ set byte_regs(11) r12l
 set byte_regs(12) r13l
 set byte_regs(13) r14l
 set byte_regs(14) r15l
+set byte_regs(15) ah
+set byte_regs(16) bh
+set byte_regs(17) ch
+set byte_regs(18) dh
 
 gdb_test "break [gdb_get_line_number "first breakpoint here"]" \
          "Breakpoint .* at .*${srcfile}.*" \
@@ -79,12 +82,19 @@ for { set r 1 } { $r <= 6  } { incr r } {
         "check contents of %$byte_regs($r)"
 }
 
+for { set r 1 } { $r <= 4  } { incr r } {
+    set h [expr $r + 14]
+    gdb_test "print/x \$$byte_regs($h)" \
+        ".. = 0x[format %x $r]2" \
+        "check contents of %$byte_regs($h)"
+}
+
 gdb_test "break [gdb_get_line_number "second breakpoint here"]" \
          "Breakpoint .* at .*${srcfile}.*" \
          "set second breakpoint in main"
 gdb_continue_to_breakpoint "continue to second breakpoint in main"
 
-for { set r 7 } { $r <= $nr_regs  } { incr r } {
+for { set r 7 } { $r <= 14  } { incr r } {
     gdb_test "print/x \$$byte_regs($r)" \
         ".. = 0x[format %x $r]1" \
         "check contents of %$byte_regs($r)"
@@ -94,6 +104,11 @@ for { set r 1 } { $r <= 6  } { incr r } {
   gdb_test "set var \$$byte_regs($r) = $r" "" "set %$byte_regs($r)"
 }
 
+for { set r 1 } { $r <= 4  } { incr r } {
+  set h [expr $r + 14]
+  gdb_test "set var \$$byte_regs($h) = $h" "" "set %$byte_regs($h)"
+}
+
 gdb_test "break [gdb_get_line_number "third breakpoint here"]" \
          "Breakpoint .* at .*${srcfile}.*" \
          "set third breakpoint in main"
@@ -105,7 +120,14 @@ for { set r 1 } { $r <= 6  } { incr r } {
         "check contents of %$byte_regs($r)"
 }
 
-for { set r 7 } { $r <= $nr_regs  } { incr r } {
+for { set r 1 } { $r <= 4  } { incr r } {
+    set h [expr $r + 14]
+    gdb_test "print \$$byte_regs($h)" \
+        ".. = $h" \
+        "check contents of %$byte_regs($h)"
+}
+
+for { set r 7 } { $r <= 14  } { incr r } {
   gdb_test "set var \$$byte_regs($r) = $r" "" "set %$byte_regs($r)"
 }
 
@@ -114,7 +136,7 @@ gdb_test "break [gdb_get_line_number "forth breakpoint here"]" \
          "set forth breakpoint in main"
 gdb_continue_to_breakpoint "continue to forth breakpoint in main"
 
-for { set r 7 } { $r <= $nr_regs  } { incr r } {
+for { set r 7 } { $r <= 14  } { incr r } {
     gdb_test "print \$$byte_regs($r)" \
         ".. = $r" \
         "check contents of %$byte_regs($r)"