binutils-gdb/gdb/testsuite/gdb.cp/classes.cc
Pedro Alves d5f96005a6 Move "register" test out of classes.exp to a separate testcase
The gdb.cp/classes.exp testcase has one test that tries to exercise
the case of calling a method on a variable that has been put in a
register.

See the declaration of small in classes.cc:

/* Try to get the compiler to allocate a class in a register.  */
class small {
 public:
  int x;
  int method ();
};

and the comment in classes.exp:

    # This class is so small that an instance of it can fit in a register.
    # When gdb tries to call a method, it gets embarrassed about taking
    # the address of a register.
    #
    # TODO: I think that message should be a PASS, not an XFAIL.
    # gdb prints an informative message and declines to do something
    # impossible.
    #
    # The method call actually succeeds if the compiler allocates very
    # small classes in memory instead of registers.  So this test does
    # not tell us anything interesting if the call succeeds.
    #
    # -- chastain 2003-12-31

And these comments:

 https://gcc.gnu.org/legacy-ml/gcc/2010-05/msg00116.html
 https://gcc.gnu.org/legacy-ml/gcc/2010-05/msg00117.html

 "register keyword has other uses, e.g. for -O0 code variables
 declared with register keyword can be put into registers, while
 variables declared without it always get stack slots."

 "I think it does, without optimization.  There's some unique GDB
 tests that use this.  It causes them to be live between statements in
 a machine register instead of always stored in stack slots."

The "register" keyword seems to be ignored by the compiler nowadays
even at -O0, though.  With or without the register keyword, the
variable is given a stack slot, at least on x86-64 with GCC 9.

However, if we use the GCC extension to put the variable
in a specific variable:

 https://gcc.gnu.org/onlinedocs/gcc-10.2.0/gcc/Local-Register-Variables.html#Local-Register-Variables

 diff --git c/gdb/testsuite/gdb.cp/classes.cc w/gdb/testsuite/gdb.cp/classes.cc
 index 5ea360e4d06..6dcf34689b8 100644
 --- c/gdb/testsuite/gdb.cp/classes.cc
 +++ w/gdb/testsuite/gdb.cp/classes.cc
 @@ -629,7 +629,7 @@ register_class ()
    /* We don't call any methods for v, so gcc version cygnus-2.3.3-930220
       might put this variable in a register.  This is a lose, though, because
       it means that GDB can't call any methods for that variable.  */
 -  register small v;
 +  register small v asm ("rax");

then it works, and we get an XFAIL:

 print v.method ()
 Address requested for identifier "v" which is in register $rax
 (gdb) XFAIL: gdb.cp/classes.exp: calling method for small class (PRMS 2972)

I think that what we should do here is move this test into its own
file, use that GCC syntax to force it to a register, and do as the
comment says -- issue a pass instead of an XFAIL.

That's what this commit does.

Note that we don't need -Wno-deprecated-register (nor -Wno-register)
anymore in the new testcase, because GNU register-asm local variables
don't trigger the warning, with either GCC or Clang.

gdb/testsuite/ChangeLog:

	* gdb.cp/classes.exp: No longer pass -Wno-deprecated-register.
	(do_tests): Remove "calling method for small class" test.
	* gdb.cp/classes.cc (class small, small::method, marker_reg1)
	(register_class): Delete.
	(main): Don't call register_class.
	* gdb.cp/call-method-register.exp: New file, based on bits removed
	from classes.exp.
	* gdb.cp/call-method-register.cc: New file, based on bits removed
	from classes.cc.
2020-09-13 15:36:00 +01:00

686 lines
12 KiB
C++

/* This testcase is part of GDB, the GNU debugger.
Copyright 1993-2020 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/>. */
// Test various -*- C++ -*- things.
// ====================== basic C++ types =======================
bool v_bool;
bool v_bool_array[2];
typedef struct fleep fleep;
struct fleep { int a; } s;
// ====================== simple class structures =======================
struct default_public_struct {
// defaults to public:
int a;
int b;
};
struct explicit_public_struct {
public:
int a;
int b;
};
struct protected_struct {
protected:
int a;
int b;
};
struct private_struct {
private:
int a;
int b;
};
struct mixed_protection_struct {
public:
int a;
int b;
private:
int c;
int d;
protected:
int e;
int f;
public:
int g;
private:
int h;
protected:
int i;
};
class public_class {
public:
int a;
int b;
};
class protected_class {
protected:
int a;
int b;
};
class default_private_class {
// defaults to private:
int a;
int b;
};
class explicit_private_class {
private:
int a;
int b;
};
class mixed_protection_class {
public:
int a;
int b;
private:
int c;
int d;
protected:
int e;
int f;
public:
int g;
private:
int h;
protected:
int i;
};
class const_vol_method_class {
public:
int a;
int b;
int foo (int &) const;
int bar (int &) volatile;
int baz (int &) const volatile;
};
int const_vol_method_class::foo (int & ir) const
{
return ir + 3;
}
int const_vol_method_class::bar (int & ir) volatile
{
return ir + 4;
}
int const_vol_method_class::baz (int & ir) const volatile
{
return ir + 5;
}
// ========================= simple inheritance ==========================
class A {
public:
int a;
int x;
};
A g_A;
class B : public A {
public:
int b;
int x;
};
B g_B;
class C : public A {
public:
int c;
int x;
};
C g_C;
class D : public B, public C {
public:
int d;
int x;
};
D g_D;
class E : public D {
public:
int e;
int x;
};
E g_E;
class class_with_anon_union
{
public:
int one;
union
{
int a;
long b;
};
};
class_with_anon_union g_anon_union;
void inheritance2 (void)
{
}
void inheritance1 (void)
{
int ival;
int *intp;
// {A::a, A::x}
g_A.A::a = 1;
g_A.A::x = 2;
// {{A::a,A::x},B::b,B::x}
g_B.A::a = 3;
g_B.A::x = 4;
g_B.B::b = 5;
g_B.B::x = 6;
// {{A::a,A::x},C::c,C::x}
g_C.A::a = 7;
g_C.A::x = 8;
g_C.C::c = 9;
g_C.C::x = 10;
// {{{A::a,A::x},B::b,B::x},{{A::a,A::x},C::c,C::x},D::d,D::x}
// The following initialization code is non-portable, but allows us
// to initialize all members of g_D until we can fill in the missing
// initialization code with legal C++ code.
for (intp = (int *) &g_D, ival = 11;
intp < ((int *) &g_D + sizeof (g_D) / sizeof (int));
intp++, ival++)
{
*intp = ival;
}
// Overlay the nonportable initialization with legal initialization.
// ????? = 11; (g_D.A::a = 11; is ambiguous)
// ????? = 12; (g_D.A::x = 12; is ambiguous)
/* djb 6-3-2000
This should take care of it. Rather than try to initialize using an ambiguous
construct, use 2 unambiguous ones for each. Since the ambiguous a/x member is
coming from C, and B, initialize D's C::a, and B::a, and D's C::x and B::x.
*/
g_D.C::a = 15;
g_D.C::x = 12;
g_D.B::a = 11;
g_D.B::x = 12;
g_D.B::b = 13;
g_D.B::x = 14;
// ????? = 15;
// ????? = 16;
g_D.C::c = 17;
g_D.C::x = 18;
g_D.D::d = 19;
g_D.D::x = 20;
// {{{{A::a,A::x},B::b,B::x},{{A::a,A::x},C::c,C::x},D::d,D::x}},E::e,E::x}
// The following initialization code is non-portable, but allows us
// to initialize all members of g_D until we can fill in the missing
// initialization code with legal C++ code.
for (intp = (int *) &g_E, ival = 21;
intp < ((int *) &g_E + sizeof (g_E) / sizeof (int));
intp++, ival++)
{
*intp = ival;
}
// Overlay the nonportable initialization with legal initialization.
// ????? = 21; (g_E.A::a = 21; is ambiguous)
// ????? = 22; (g_E.A::x = 22; is ambiguous)
g_E.B::b = 23;
g_E.B::x = 24;
// ????? = 25;
// ????? = 26;
g_E.C::c = 27;
g_E.C::x = 28;
g_E.D::d = 29;
g_E.D::x = 30;
g_E.E::e = 31;
g_E.E::x = 32;
g_anon_union.one = 1;
g_anon_union.a = 2;
inheritance2 ();
}
// ======================== static member functions =====================
class Static {
public:
static void ii(int, int);
};
void Static::ii (int, int) { }
// ======================== virtual base classes=========================
class vA {
public:
int va;
int vx;
};
vA g_vA;
class vB : public virtual vA {
public:
int vb;
int vx;
};
vB g_vB;
class vC : public virtual vA {
public:
int vc;
int vx;
};
vC g_vC;
class vD : public virtual vB, public virtual vC {
public:
int vd;
int vx;
};
vD g_vD;
class vE : public virtual vD {
public:
int ve;
int vx;
};
vE g_vE;
void inheritance4 (void)
{
}
void inheritance3 (void)
{
int ival;
int *intp;
// {vA::va, vA::vx}
g_vA.vA::va = 1;
g_vA.vA::vx = 2;
// {{vA::va, vA::vx}, vB::vb, vB::vx}
g_vB.vA::va = 3;
g_vB.vA::vx = 4;
g_vB.vB::vb = 5;
g_vB.vB::vx = 6;
// {{vA::va, vA::vx}, vC::vc, vC::vx}
g_vC.vA::va = 7;
g_vC.vA::vx = 8;
g_vC.vC::vc = 9;
g_vC.vC::vx = 10;
// {{{{vA::va, vA::vx}, vB::vb, vB::vx}, vC::vc, vC::vx}, vD::vd,vD::vx}
g_vD.vA::va = 11;
g_vD.vA::vx = 12;
g_vD.vB::vb = 13;
g_vD.vB::vx = 14;
g_vD.vC::vc = 15;
g_vD.vC::vx = 16;
g_vD.vD::vd = 17;
g_vD.vD::vx = 18;
// {{{{{vA::va,vA::vx},vB::vb,vB::vx},vC::vc,vC::vx},vD::vd,vD::vx},vE::ve,vE::vx}
g_vD.vA::va = 19;
g_vD.vA::vx = 20;
g_vD.vB::vb = 21;
g_vD.vB::vx = 22;
g_vD.vC::vc = 23;
g_vD.vC::vx = 24;
g_vD.vD::vd = 25;
g_vD.vD::vx = 26;
g_vE.vE::ve = 27;
g_vE.vE::vx = 28;
inheritance4 ();
}
// ======================================================================
class Base1 {
public:
int x;
Base1(int i) { x = i; }
~Base1 () { }
};
typedef Base1 base1;
class Foo
{
public:
int x;
int y;
static int st;
Foo (int i, int j) { x = i; y = j; }
int operator! ();
operator int ();
int times (int y);
};
typedef Foo ByAnyOtherName;
class Bar : public Base1, public Foo {
public:
int z;
Bar (int i, int j, int k) : Base1 (10*k), Foo (i, j) { z = k; }
};
int Foo::operator! () { return !x; }
int Foo::times (int y) { return x * y; }
int Foo::st = 100;
Foo::operator int() { return x; }
ByAnyOtherName foo(10, 11);
Bar bar(20, 21, 22);
/* Use a typedef for the baseclass to exercise gnu-v3-abi.c:gnuv3_dynamic_class
recursion. It's important that the class itself have no name to make sure
the typedef makes it through to the recursive call. */
typedef class {
public:
int x;
virtual int get_x () { return x; }
} DynamicBase2;
class DynamicBar : public DynamicBase2
{
public:
DynamicBar (int i, int j) { x = i; y = j; }
int y;
};
DynamicBar dynbar (23, 24);
class ClassWithEnum {
public:
enum PrivEnum { red, green, blue, yellow = 42 };
PrivEnum priv_enum;
int x;
};
void enums2 (void)
{
}
/* classes.exp relies on statement order in this function for testing
enumeration fields. */
void enums1 ()
{
ClassWithEnum obj_with_enum;
obj_with_enum.priv_enum = ClassWithEnum::red;
obj_with_enum.x = 0;
enums2 ();
obj_with_enum.priv_enum = ClassWithEnum::green;
obj_with_enum.x = 1;
}
class ClassParam {
public:
int Aptr_a (A *a) { return a->a; }
int Aptr_x (A *a) { return a->x; }
int Aref_a (A &a) { return a.a; }
int Aref_x (A &a) { return a.x; }
int Aval_a (A a) { return a.a; }
int Aval_x (A a) { return a.x; }
};
ClassParam class_param;
class Contains_static_instance
{
public:
int x;
int y;
Contains_static_instance (int i, int j) { x = i; y = j; }
static Contains_static_instance null;
};
Contains_static_instance Contains_static_instance::null(0,0);
Contains_static_instance csi(10,20);
class Contains_nested_static_instance
{
public:
class Nested
{
public:
Nested(int i) : z(i) {}
int z;
static Contains_nested_static_instance xx;
};
Contains_nested_static_instance(int i, int j) : x(i), y(j) {}
int x;
int y;
static Contains_nested_static_instance null;
static Nested yy;
};
Contains_nested_static_instance Contains_nested_static_instance::null(0, 0);
Contains_nested_static_instance::Nested Contains_nested_static_instance::yy(5);
Contains_nested_static_instance
Contains_nested_static_instance::Nested::xx(1,2);
Contains_nested_static_instance cnsi(30,40);
typedef struct {
int one;
int two;
} tagless_struct;
tagless_struct v_tagless;
class class_with_typedefs
{
public:
typedef int public_int;
protected:
typedef int protected_int;
private:
typedef int private_int;
public:
class_with_typedefs ()
: public_int_ (1), protected_int_ (2), private_int_ (3) {}
public_int add_public (public_int a) { return a + public_int_; }
public_int add_all (int a)
{ return add_public (a) + add_protected (a) + add_private (a); }
protected:
protected_int add_protected (protected_int a) { return a + protected_int_; }
private:
private_int add_private (private_int a) { return a + private_int_; }
protected:
public_int public_int_;
protected_int protected_int_;
private_int private_int_;
};
class class_with_public_typedef
{
int a;
public:
typedef int INT;
INT b;
};
class class_with_protected_typedef
{
int a;
protected:
typedef int INT;
INT b;
};
class class_with_private_typedef
{
int a;
private:
typedef int INT;
INT b;
};
struct struct_with_public_typedef
{
int a;
public:
typedef int INT;
INT b;
};
struct struct_with_protected_typedef
{
int a;
protected:
typedef int INT;
INT b;
};
struct struct_with_private_typedef
{
int a;
private:
typedef int INT;
INT b;
};
void dummy()
{
v_bool = true;
v_bool_array[0] = false;
v_bool_array[1] = v_bool;
}
void use_methods ()
{
/* Refer to methods so that they don't get optimized away. */
int i;
i = class_param.Aptr_a (&g_A);
i = class_param.Aptr_x (&g_A);
i = class_param.Aref_a (g_A);
i = class_param.Aref_x (g_A);
i = class_param.Aval_a (g_A);
i = class_param.Aval_x (g_A);
base1 b (3);
}
struct Inner
{
static Inner instance;
};
struct Outer
{
Inner inner;
static Outer instance;
};
Inner Inner::instance;
Outer Outer::instance;
int
main()
{
dummy();
inheritance1 ();
inheritance3 ();
enums1 ();
/* FIXME: pmi gets optimized out. Need to do some more computation with
it or something. (No one notices, because the test is xfail'd anyway,
but that probably won't always be true...). */
int Foo::* pmi = &Foo::y;
/* Make sure the AIX linker doesn't remove the variable. */
v_tagless.one = 5;
use_methods ();
return foo.*pmi;
}
/* Create an instance for some classes, otherwise they get optimized away. */
default_public_struct default_public_s;
explicit_public_struct explicit_public_s;
protected_struct protected_s;
private_struct private_s;
mixed_protection_struct mixed_protection_s;
public_class public_c;
protected_class protected_c;
default_private_class default_private_c;
explicit_private_class explicit_private_c;
mixed_protection_class mixed_protection_c;
class_with_typedefs class_with_typedefs_c;
class_with_public_typedef class_with_public_typedef_c;
class_with_protected_typedef class_with_protected_typedef_c;
class_with_private_typedef class_with_private_typedef_c;
struct_with_public_typedef struct_with_public_typedef_s;
struct_with_protected_typedef struct_with_protected_typedef_s;
struct_with_private_typedef struct_with_private_typedef_s;