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[RFA/commit 1/3] amd64: Integer parameters in function calls on Windows.
- From: Joel Brobecker <brobecker at adacore dot com>
- To: gdb-patches at sourceware dot org
- Date: Mon, 25 Jan 2010 09:42:10 +0400
- Subject: [RFA/commit 1/3] amd64: Integer parameters in function calls on Windows.
- References: <1264398132-1429-1-git-send-email-brobecker@adacore.com>
From: brobecke <brobecke@f8352e7e-cb20-0410-8ce7-b5d9e71c585c>
First problem found regarding function calls on amd64-windows:
Integer parameters are not passed correctly. After investigation,
I realized that the registers used for integer parameter passing
are quite different from the registers used on Linux. On Windows,
the registers are (used in this order): rcx, rdx, r8 and r9.
http://msdn.microsoft.com/en-us/magazine/cc300794.aspx
As a quick reference, the registers used on Linux are: rsi, rdi, and
then rdx, rcx, r8, r9.
The solution I chose was to store that information in the gdbarch_tdep
structure. This information is then used by the various routines that
deal with parameter passing and value returns, instead of using a hard-
coded list of registers.
The heart of the change in the addition of 3 fields in gdbarch_tdep
in i386-tdep.h. The rest is just extracting out the OS-dependent
portions and putting them into the OS-dependent implementations of
the new gdbarch_tdep routines.
gdb/ChangeLog:
* i386-tdep.h (enum amd64_reg_class): New, moved here from
amd64-tdep.c.
(struct gdbarch_tdep): Add fields call_dummy_num_integer_regs,
call_dummy_integer_regs, and classify.
* amd64-tdep.h (amd64_classify): Add declaration.
* amd64-tdep.c (amd64_dummy_call_integer_regs): New static constant.
(amd64_reg_class): Delete, moved to i386-tdep.h.
(amd64_classify): Make non-static. Move declaration to amd64-tdep.h.
Replace call to amd64_classify by call to tdep->classify.
(amd64_push_arguments): Get the list of registers to use for
passing integer parameters from the gdbarch tdep structure,
rather than using a hardcoded one. Replace calls to amd64_classify
by calls to tdep->classify.
(amd64_push_dummy_call): Get the register number used for
the "hidden" argument from tdep->call_dummy_integer_regs.
(amd64_init_abi): Initialize tdep->call_dummy_num_integer_regs
and tdep->call_dummy_integer_regs. Set tdep->classify.
* amd64-windows-tdep.c: Add include of gdbtypes.h.
(amd64_windows_dummy_call_integer_regs): New static global.
(amd64_windows_classify): New function.
(amd64_windows_init_abi): Initialize tdep->call_dummy_num_integer_regs
tdep->call_dummy_integer_regs and tdep->classify.
gdb/testsuite/ChangeLog:
* gdb.ada/call_pn: New testcase.
---
gdb/amd64-tdep.c | 65 +++++++++++++++++----------------
gdb/amd64-tdep.h | 3 ++
gdb/amd64-windows-tdep.c | 55 ++++++++++++++++++++++++++++
gdb/i386-tdep.h | 24 ++++++++++++
gdb/testsuite/gdb.ada/call_pn.exp | 53 +++++++++++++++++++++++++++
gdb/testsuite/gdb.ada/call_pn/foo.adb | 23 ++++++++++++
gdb/testsuite/gdb.ada/call_pn/pck.adb | 25 +++++++++++++
gdb/testsuite/gdb.ada/call_pn/pck.ads | 23 ++++++++++++
8 files changed, 240 insertions(+), 31 deletions(-)
create mode 100644 gdb/testsuite/gdb.ada/call_pn.exp
create mode 100644 gdb/testsuite/gdb.ada/call_pn/foo.adb
create mode 100644 gdb/testsuite/gdb.ada/call_pn/pck.adb
create mode 100644 gdb/testsuite/gdb.ada/call_pn/pck.ads
diff --git a/gdb/amd64-tdep.c b/gdb/amd64-tdep.c
index 9f5d330..f69f3f6 100644
--- a/gdb/amd64-tdep.c
+++ b/gdb/amd64-tdep.c
@@ -72,6 +72,17 @@ static const char *amd64_register_names[] =
/* Total number of registers. */
#define AMD64_NUM_REGS ARRAY_SIZE (amd64_register_names)
+/* The registers used to pass integer arguments during a function call. */
+static int amd64_dummy_call_integer_regs[] =
+{
+ AMD64_RDI_REGNUM, /* %rdi */
+ AMD64_RSI_REGNUM, /* %rsi */
+ AMD64_RDX_REGNUM, /* %rdx */
+ AMD64_RCX_REGNUM, /* %rcx */
+ 8, /* %r8 */
+ 9 /* %r9 */
+};
+
/* Return the name of register REGNUM. */
const char *
@@ -240,20 +251,6 @@ amd64_arch_reg_to_regnum (int reg)
-/* Register classes as defined in the psABI. */
-
-enum amd64_reg_class
-{
- AMD64_INTEGER,
- AMD64_SSE,
- AMD64_SSEUP,
- AMD64_X87,
- AMD64_X87UP,
- AMD64_COMPLEX_X87,
- AMD64_NO_CLASS,
- AMD64_MEMORY
-};
-
/* Return the union class of CLASS1 and CLASS2. See the psABI for
details. */
@@ -290,8 +287,6 @@ amd64_merge_classes (enum amd64_reg_class class1, enum amd64_reg_class class2)
return AMD64_SSE;
}
-static void amd64_classify (struct type *type, enum amd64_reg_class class[2]);
-
/* Return non-zero if TYPE is a non-POD structure or union type. */
static int
@@ -413,7 +408,7 @@ amd64_classify_aggregate (struct type *type, enum amd64_reg_class class[2])
/* Classify TYPE, and store the result in CLASS. */
-static void
+void
amd64_classify (struct type *type, enum amd64_reg_class class[2])
{
enum type_code code = TYPE_CODE (type);
@@ -464,6 +459,7 @@ amd64_return_value (struct gdbarch *gdbarch, struct type *func_type,
struct type *type, struct regcache *regcache,
gdb_byte *readbuf, const gdb_byte *writebuf)
{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
enum amd64_reg_class class[2];
int len = TYPE_LENGTH (type);
static int integer_regnum[] = { AMD64_RAX_REGNUM, AMD64_RDX_REGNUM };
@@ -473,9 +469,10 @@ amd64_return_value (struct gdbarch *gdbarch, struct type *func_type,
int i;
gdb_assert (!(readbuf && writebuf));
+ gdb_assert (tdep->classify);
/* 1. Classify the return type with the classification algorithm. */
- amd64_classify (type, class);
+ tdep->classify (type, class);
/* 2. If the type has class MEMORY, then the caller provides space
for the return value and passes the address of this storage in
@@ -573,15 +570,10 @@ static CORE_ADDR
amd64_push_arguments (struct regcache *regcache, int nargs,
struct value **args, CORE_ADDR sp, int struct_return)
{
- static int integer_regnum[] =
- {
- AMD64_RDI_REGNUM, /* %rdi */
- AMD64_RSI_REGNUM, /* %rsi */
- AMD64_RDX_REGNUM, /* %rdx */
- AMD64_RCX_REGNUM, /* %rcx */
- 8, /* %r8 */
- 9 /* %r9 */
- };
+ struct gdbarch_tdep *tdep = gdbarch_tdep (get_regcache_arch (regcache));
+ int *integer_regs = tdep->call_dummy_integer_regs;
+ int num_integer_regs = tdep->call_dummy_num_integer_regs;
+
static int sse_regnum[] =
{
/* %xmm0 ... %xmm7 */
@@ -598,6 +590,8 @@ amd64_push_arguments (struct regcache *regcache, int nargs,
int sse_reg = 0;
int i;
+ gdb_assert (tdep->classify);
+
/* Reserve a register for the "hidden" argument. */
if (struct_return)
integer_reg++;
@@ -612,7 +606,7 @@ amd64_push_arguments (struct regcache *regcache, int nargs,
int j;
/* Classify argument. */
- amd64_classify (type, class);
+ tdep->classify (type, class);
/* Calculate the number of integer and SSE registers needed for
this argument. */
@@ -626,7 +620,7 @@ amd64_push_arguments (struct regcache *regcache, int nargs,
/* Check whether enough registers are available, and if the
argument should be passed in registers at all. */
- if (integer_reg + needed_integer_regs > ARRAY_SIZE (integer_regnum)
+ if (integer_reg + needed_integer_regs > num_integer_regs
|| sse_reg + needed_sse_regs > ARRAY_SIZE (sse_regnum)
|| (needed_integer_regs == 0 && needed_sse_regs == 0))
{
@@ -650,7 +644,7 @@ amd64_push_arguments (struct regcache *regcache, int nargs,
switch (class[j])
{
case AMD64_INTEGER:
- regnum = integer_regnum[integer_reg++];
+ regnum = integer_regs[integer_reg++];
break;
case AMD64_SSE:
@@ -716,8 +710,13 @@ amd64_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
/* Pass "hidden" argument". */
if (struct_return)
{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ /* The "hidden" argument is passed throught the first argument
+ register. */
+ const int arg_regnum = tdep->call_dummy_integer_regs[0];
+
store_unsigned_integer (buf, 8, byte_order, struct_addr);
- regcache_cooked_write (regcache, AMD64_RDI_REGNUM, buf);
+ regcache_cooked_write (regcache, arg_regnum, buf);
}
/* Store return address. */
@@ -2164,6 +2163,10 @@ amd64_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
set_gdbarch_push_dummy_call (gdbarch, amd64_push_dummy_call);
set_gdbarch_frame_align (gdbarch, amd64_frame_align);
set_gdbarch_frame_red_zone_size (gdbarch, 128);
+ tdep->call_dummy_num_integer_regs =
+ ARRAY_SIZE (amd64_dummy_call_integer_regs);
+ tdep->call_dummy_integer_regs = amd64_dummy_call_integer_regs;
+ tdep->classify = amd64_classify;
set_gdbarch_convert_register_p (gdbarch, i387_convert_register_p);
set_gdbarch_register_to_value (gdbarch, i387_register_to_value);
diff --git a/gdb/amd64-tdep.h b/gdb/amd64-tdep.h
index 3bff5d1..363479c 100644
--- a/gdb/amd64-tdep.h
+++ b/gdb/amd64-tdep.h
@@ -98,6 +98,9 @@ extern void amd64_supply_fxsave (struct regcache *regcache, int regnum,
extern void amd64_collect_fxsave (const struct regcache *regcache, int regnum,
void *fxsave);
+
+void amd64_classify (struct type *type, enum amd64_reg_class class[2]);
+
/* Variables exported from amd64nbsd-tdep.c. */
diff --git a/gdb/amd64-windows-tdep.c b/gdb/amd64-windows-tdep.c
index bdad9bd..b5a0035 100644
--- a/gdb/amd64-windows-tdep.c
+++ b/gdb/amd64-windows-tdep.c
@@ -20,15 +20,70 @@
#include "amd64-tdep.h"
#include "solib.h"
#include "solib-target.h"
+#include "gdbtypes.h"
+
+/* The registers used to pass integer arguments during a function call. */
+static int amd64_windows_dummy_call_integer_regs[] =
+{
+ AMD64_RCX_REGNUM, /* %rcx */
+ AMD64_RDX_REGNUM, /* %rdx */
+ 8, /* %r8 */
+ 9 /* %r9 */
+};
+
+/* Implement the "classify" method in the gdbarch_tdep structure
+ for amd64-windows. */
+
+static void
+amd64_windows_classify (struct type *type, enum amd64_reg_class class[2])
+{
+ switch (TYPE_CODE (type))
+ {
+ case TYPE_CODE_ARRAY:
+ /* Arrays are always passed by memory. */
+ class[0] = class[1] = AMD64_MEMORY;
+ break;
+
+ case TYPE_CODE_STRUCT:
+ case TYPE_CODE_UNION:
+ /* Struct/Union types whose size is 1, 2, 4, or 8 bytes
+ are passed as if they were integers of the same size.
+ Types of different sizes are passed by memory. */
+ if (TYPE_LENGTH (type) == 1
+ || TYPE_LENGTH (type) == 2
+ || TYPE_LENGTH (type) == 4
+ || TYPE_LENGTH (type) == 8)
+ {
+ class[0] = AMD64_INTEGER;
+ class[1] = AMD64_NO_CLASS;
+ }
+ else
+ class[0] = class[1] = AMD64_MEMORY;
+ break;
+
+ default:
+ /* For all the other types, the conventions are the same as
+ with the System V ABI. */
+ amd64_classify (type, class);
+ }
+}
static void
amd64_windows_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
amd64_init_abi (info, gdbarch);
/* On Windows, "long"s are only 32bit. */
set_gdbarch_long_bit (gdbarch, 32);
+ /* Function calls. */
+ tdep->call_dummy_num_integer_regs =
+ ARRAY_SIZE (amd64_windows_dummy_call_integer_regs);
+ tdep->call_dummy_integer_regs = amd64_windows_dummy_call_integer_regs;
+ tdep->classify = amd64_windows_classify;
+
set_solib_ops (gdbarch, &solib_target_so_ops);
}
diff --git a/gdb/i386-tdep.h b/gdb/i386-tdep.h
index 6013bdf..d5b24fa 100644
--- a/gdb/i386-tdep.h
+++ b/gdb/i386-tdep.h
@@ -53,6 +53,20 @@ enum struct_return
reg_struct_return /* Return "short" structures in registers. */
};
+/* Register classes as defined in the AMD x86-64 psABI. */
+
+enum amd64_reg_class
+{
+ AMD64_INTEGER,
+ AMD64_SSE,
+ AMD64_SSEUP,
+ AMD64_X87,
+ AMD64_X87UP,
+ AMD64_COMPLEX_X87,
+ AMD64_NO_CLASS,
+ AMD64_MEMORY
+};
+
/* i386 architecture specific information. */
struct gdbarch_tdep
{
@@ -62,6 +76,16 @@ struct gdbarch_tdep
int gregset_num_regs;
size_t sizeof_gregset;
+ /* The general-purpose registers used to pass integers when making
+ function calls. This only applies to amd64, as all parameters
+ are passed through the stack on x86. */
+ int call_dummy_num_integer_regs;
+ int *call_dummy_integer_regs;
+
+ /* Classify TYPE according to calling conventions, and store
+ the result in CLASS. Used on amd64 only. */
+ void (*classify) (struct type *type, enum amd64_reg_class class[2]);
+
/* Floating-point registers. */
struct regset *fpregset;
size_t sizeof_fpregset;
diff --git a/gdb/testsuite/gdb.ada/call_pn.exp b/gdb/testsuite/gdb.ada/call_pn.exp
new file mode 100644
index 0000000..5ade3fa
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/call_pn.exp
@@ -0,0 +1,53 @@
+# Copyright 2010 Free Software Foundation, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+if $tracelevel then {
+ strace $tracelevel
+}
+
+load_lib "ada.exp"
+
+set testdir "call_pn"
+set testfile "${testdir}/foo"
+set srcfile ${srcdir}/${subdir}/${testfile}.adb
+set binfile ${objdir}/${subdir}/${testfile}
+
+file mkdir ${objdir}/${subdir}/${testdir}
+if {[gdb_compile_ada "${srcfile}" "${binfile}" executable [list debug ]] != "" } {
+ return -1
+}
+
+gdb_exit
+gdb_start
+gdb_reinitialize_dir $srcdir/$subdir
+gdb_load ${binfile}
+
+set bp_location [gdb_get_line_number "STOP" ${testdir}/foo.adb]
+if ![runto "foo.adb:$bp_location" ] then {
+ perror "Couldn't run ${testfile}"
+ return
+}
+
+# Make sure that last_node_id is set to zero...
+gdb_test "print last_node_id" "= 0" "print last_node_id before calling pn"
+
+# Now, call procedure Pn, which should set Last_Node_Id to the value
+# of the parameter used in the function call. Verify that we can print
+# the returned value correctly, while we're at it.
+gdb_test "print pn (4321)" "= 4321" "print pn (4321)"
+
+# Make sure that last_node_id now has the correct value...
+gdb_test "print last_node_id" "= 4321" "print last_node_id after calling pn"
+
diff --git a/gdb/testsuite/gdb.ada/call_pn/foo.adb b/gdb/testsuite/gdb.ada/call_pn/foo.adb
new file mode 100644
index 0000000..a71969b
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/call_pn/foo.adb
@@ -0,0 +1,23 @@
+-- Copyright 2010 Free Software Foundation, Inc.
+--
+-- This program is free software; you can redistribute it and/or modify
+-- it under the terms of the GNU General Public License as published by
+-- the Free Software Foundation; either version 3 of the License, or
+-- (at your option) any later version.
+--
+-- This program is distributed in the hope that it will be useful,
+-- but WITHOUT ANY WARRANTY; without even the implied warranty of
+-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+-- GNU General Public License for more details.
+--
+-- You should have received a copy of the GNU General Public License
+-- along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+with Pck; use Pck;
+
+procedure Foo is
+ New_Node : Node_Id;
+begin
+ New_Node := Pn (1234); -- STOP
+end Foo;
+
diff --git a/gdb/testsuite/gdb.ada/call_pn/pck.adb b/gdb/testsuite/gdb.ada/call_pn/pck.adb
new file mode 100644
index 0000000..cc2dfb6
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/call_pn/pck.adb
@@ -0,0 +1,25 @@
+-- Copyright 2010 Free Software Foundation, Inc.
+--
+-- This program is free software; you can redistribute it and/or modify
+-- it under the terms of the GNU General Public License as published by
+-- the Free Software Foundation; either version 3 of the License, or
+-- (at your option) any later version.
+--
+-- This program is distributed in the hope that it will be useful,
+-- but WITHOUT ANY WARRANTY; without even the implied warranty of
+-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+-- GNU General Public License for more details.
+--
+-- You should have received a copy of the GNU General Public License
+-- along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+package body Pck is
+ Last_Node_Id : Node_Id := Node_Id'First;
+
+ function Pn (N : Node_Id) return Node_Id is
+ begin
+ Last_Node_Id := N;
+ return N;
+ end Pn;
+end Pck;
+
diff --git a/gdb/testsuite/gdb.ada/call_pn/pck.ads b/gdb/testsuite/gdb.ada/call_pn/pck.ads
new file mode 100644
index 0000000..11e21c3
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/call_pn/pck.ads
@@ -0,0 +1,23 @@
+-- Copyright 2010 Free Software Foundation, Inc.
+--
+-- This program is free software; you can redistribute it and/or modify
+-- it under the terms of the GNU General Public License as published by
+-- the Free Software Foundation; either version 3 of the License, or
+-- (at your option) any later version.
+--
+-- This program is distributed in the hope that it will be useful,
+-- but WITHOUT ANY WARRANTY; without even the implied warranty of
+-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+-- GNU General Public License for more details.
+--
+-- You should have received a copy of the GNU General Public License
+-- along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+package Pck is
+ Node_Low_Bound : constant := 0;
+ Node_High_Bound : constant := 099_999_999;
+ type Node_Id is range Node_Low_Bound .. Node_High_Bound;
+
+ function Pn (N : Node_Id) return Node_Id;
+end Pck;
+
--
1.6.3.3