From: Trevor Saunders <tbsaunde+...@tbsaunde.org>
Hi,
$subject. To avoid regressions I kept the checks when generating rtl, but I
believe its impossible for those to trigger now and we can remove the checks.
bootstrapped + regtested on x86_64-linux-gnu, ok?
Trev
gcc/c/ChangeLog:
2016-01-25 Trevor Saunders <tbsaunde+...@tbsaunde.org>
* c-decl.c (finish_decl): Check if asm register is valid.
gcc/ChangeLog:
2016-01-25 Trevor Saunders <tbsaunde+...@tbsaunde.org>
* varasm.c (register_asmspec_ok_p): New function.
(make_decl_rtl): Adjust.
* varasm.h (register_asmspec_ok_p): New prototype.
gcc/cp/ChangeLog:
2016-01-25 Trevor Saunders <tbsaunde+...@tbsaunde.org>
* decl.c (make_rtl_for_nonlocal_decl): Check if register asm is
valid.
---
gcc/c/c-decl.c | 8 +-
gcc/cp/decl.c | 4 +-
gcc/testsuite/g++.dg/torture/register-asm-1.C | 14 +++
gcc/testsuite/gcc.dg/reg-vol-struct-1.c | 2 +-
gcc/testsuite/gcc.dg/torture/register-asm-1.c | 12 +++
gcc/varasm.c | 150 +++++++++++++++-----------
gcc/varasm.h | 3 +
7 files changed, 129 insertions(+), 64 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/torture/register-asm-1.C
create mode 100644 gcc/testsuite/gcc.dg/torture/register-asm-1.c
diff --git a/gcc/c/c-decl.c b/gcc/c/c-decl.c
index 1ec6042..9257f35 100644
--- a/gcc/c/c-decl.c
+++ b/gcc/c/c-decl.c
@@ -4867,7 +4867,9 @@ finish_decl (tree decl, location_t init_loc, tree init,
when a tentative file-scope definition is seen.
But at end of compilation, do output code for them. */
DECL_DEFER_OUTPUT (decl) = 1;
- if (asmspec && C_DECL_REGISTER (decl))
+ if (asmspec
+ && C_DECL_REGISTER (decl)
+ && register_asmspec_ok_p (decl, asmspec, DECL_MODE (decl)))
DECL_HARD_REGISTER (decl) = 1;
rest_of_decl_compilation (decl, true, 0);
}
@@ -4878,7 +4880,9 @@ finish_decl (tree decl, location_t init_loc, tree init,
in a particular register. */
if (asmspec && C_DECL_REGISTER (decl))
{
- DECL_HARD_REGISTER (decl) = 1;
+ if (register_asmspec_ok_p (decl, asmspec, DECL_MODE (decl)))
+ DECL_HARD_REGISTER (decl) = 1;
+
/* This cannot be done for a structure with volatile
fields, on which DECL_REGISTER will have been
reset. */
diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index f4604b6..6d130bd 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -6201,7 +6201,9 @@ make_rtl_for_nonlocal_decl (tree decl, tree init, const
char* asmspec)
/* The `register' keyword, when used together with an
asm-specification, indicates that the variable should be
placed in a particular register. */
- if (VAR_P (decl) && DECL_REGISTER (decl))
+ if (VAR_P (decl)
+ && DECL_REGISTER (decl)
+ && register_asmspec_ok_p (decl, asmspec, DECL_MODE (decl)))
{
set_user_assembler_name (decl, asmspec);
DECL_HARD_REGISTER (decl) = 1;
diff --git a/gcc/testsuite/g++.dg/torture/register-asm-1.C
b/gcc/testsuite/g++.dg/torture/register-asm-1.C
new file mode 100644
index 0000000..b5cfc84
--- /dev/null
+++ b/gcc/testsuite/g++.dg/torture/register-asm-1.C
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+
+class A {
+ int m_fn1() const;
+};
+int a[1];
+int b;
+int A::m_fn1() const {
+ register int c asm(""); // { dg-error "invalid register name for 'c'" }
+ while (b)
+ if (a[5])
+ c = b;
+ return c;
+}
diff --git a/gcc/testsuite/gcc.dg/reg-vol-struct-1.c
b/gcc/testsuite/gcc.dg/reg-vol-struct-1.c
index b885f91..e67c7a2 100644
--- a/gcc/testsuite/gcc.dg/reg-vol-struct-1.c
+++ b/gcc/testsuite/gcc.dg/reg-vol-struct-1.c
@@ -12,7 +12,7 @@ f (void)
{
register struct S a;
register struct S b[2];
- register struct S c __asm__("nosuchreg"); /* { dg-error "object with
volatile field" "explicit reg name" } */
+ register struct S c __asm__("nosuchreg"); /* { dg-error "invalid register
name for 'c'|cannot put object with volatile field into register" } */
&a; /* { dg-error "address of register" "explicit address" } */
b; /* { dg-error "address of register" "implicit address" } */
}
diff --git a/gcc/testsuite/gcc.dg/torture/register-asm-1.c
b/gcc/testsuite/gcc.dg/torture/register-asm-1.c
new file mode 100644
index 0000000..1949f62
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/register-asm-1.c
@@ -0,0 +1,12 @@
+/* { dg-do compile } */
+
+ int a[1], b;
+int
+foo ()
+{
+ register int c asm (""); /* { dg-error "invalid register name for 'c'" } */
+ while (b)
+ if (a[5])
+ c = b;
+ return c;
+}
diff --git a/gcc/varasm.c b/gcc/varasm.c
index 3a3573e..7e3aebc9 100644
--- a/gcc/varasm.c
+++ b/gcc/varasm.c
@@ -1270,6 +1270,55 @@ ultimate_transparent_alias_target (tree *alias)
return target;
}
+/* Check that a register asm spec is correct, and compatibility with
+ machine_mode mode. If reg_number is nonnull and the spec is valid then set
+ it to the register number designated by the spec. */
+
+bool
+register_asmspec_ok_p (tree decl, const char *asmspec, machine_mode mode,
+ int *reg_number)
+{
+ int reg = decode_reg_name (asmspec);
+ if (reg == -1)
+ {
+ error ("register name not specified for %q+D", decl);
+ return false;
+ }
+ else if (reg < 0)
+ {
+ error ("invalid register name for %q+D", decl);
+ return false;
+ }
+ else if (mode == BLKmode)
+ {
+ error ("data type of %q+D isn%'t suitable for a register", decl);
+ return false;
+ }
+ else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg))
+ {
+ error ("the register specified for %q+D cannot be accessed"
+ " by the current target", decl);
+ return false;
+ }
+ else if (!in_hard_reg_set_p (operand_reg_set, mode, reg))
+ {
+ error ("the register specified for %q+D is not general enough"
+ " to be used as a register variable", decl);
+ return false;
+ }
+ else if (!HARD_REGNO_MODE_OK (reg, mode))
+ {
+ error ("register specified for %q+D isn%'t suitable for data type",
+ decl);
+ return false;
+ }
+
+ if (reg_number)
+ *reg_number = reg;
+
+ return true;
+}
+
/* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
have static storage duration. In other words, it should not be an
automatic variable, including PARM_DECLs.
@@ -1283,7 +1332,6 @@ void
make_decl_rtl (tree decl)
{
const char *name = 0;
- int reg_number;
tree id;
rtx x;
@@ -1358,73 +1406,55 @@ make_decl_rtl (tree decl)
{
const char *asmspec = name+1;
machine_mode mode = DECL_MODE (decl);
- reg_number = decode_reg_name (asmspec);
- /* First detect errors in declaring global registers. */
- if (reg_number == -1)
- error ("register name not specified for %q+D", decl);
- else if (reg_number < 0)
- error ("invalid register name for %q+D", decl);
- else if (mode == BLKmode)
- error ("data type of %q+D isn%'t suitable for a register",
- decl);
- else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
- error ("the register specified for %q+D cannot be accessed"
- " by the current target", decl);
- else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
- error ("the register specified for %q+D is not general enough"
- " to be used as a register variable", decl);
- else if (!HARD_REGNO_MODE_OK (reg_number, mode))
- error ("register specified for %q+D isn%'t suitable for data type",
- decl);
- /* Now handle properly declared static register variables. */
- else
+ int reg_number;
+ if (!register_asmspec_ok_p (decl, asmspec, mode, ®_number))
{
- int nregs;
+ /* Avoid internal errors from invalid register
+ specifications. */
+ SET_DECL_ASSEMBLER_NAME (decl, NULL_TREE);
+ DECL_HARD_REGISTER (decl) = 0;
+ /* Also avoid SSA inconsistencies by pretending this is an external
+ decl now. */
+ DECL_EXTERNAL (decl) = 1;
+ return;
+ }
- if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
- {
- DECL_INITIAL (decl) = 0;
- error ("global register variable has initial value");
- }
- if (TREE_THIS_VOLATILE (decl))
- warning (OPT_Wvolatile_register_var,
- "optimization may eliminate reads and/or "
- "writes to register variables");
- /* If the user specified one of the eliminables registers here,
- e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
- confused with that register and be eliminated. This usage is
- somewhat suspect... */
+ if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
+ {
+ DECL_INITIAL (decl) = 0;
+ error ("global register variable has initial value");
+ }
+ if (TREE_THIS_VOLATILE (decl))
+ warning (OPT_Wvolatile_register_var,
+ "optimization may eliminate reads and/or "
+ "writes to register variables");
- SET_DECL_RTL (decl, gen_raw_REG (mode, reg_number));
- ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
- REG_USERVAR_P (DECL_RTL (decl)) = 1;
+ /* If the user specified one of the eliminables registers here,
+ e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
+ confused with that register and be eliminated. This usage is
+ somewhat suspect... */
- if (TREE_STATIC (decl))
- {
- /* Make this register global, so not usable for anything
- else. */
+ SET_DECL_RTL (decl, gen_raw_REG (mode, reg_number));
+ ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
+ REG_USERVAR_P (DECL_RTL (decl)) = 1;
+
+ if (TREE_STATIC (decl))
+ {
+ /* Make this register global, so not usable for anything
+ else. */
#ifdef ASM_DECLARE_REGISTER_GLOBAL
- name = IDENTIFIER_POINTER (DECL_NAME (decl));
- ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number,
name);
+ name = IDENTIFIER_POINTER (DECL_NAME (decl));
+ ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
#endif
- nregs = hard_regno_nregs[reg_number][mode];
- while (nregs > 0)
- globalize_reg (decl, reg_number + --nregs);
- }
-
- /* As a register variable, it has no section. */
- return;
+ int nregs = hard_regno_nregs[reg_number][mode];
+ while (nregs > 0)
+ globalize_reg (decl, reg_number + --nregs);
}
- /* Avoid internal errors from invalid register
- specifications. */
- SET_DECL_ASSEMBLER_NAME (decl, NULL_TREE);
- DECL_HARD_REGISTER (decl) = 0;
- /* Also avoid SSA inconsistencies by pretending this is an external
- decl now. */
- DECL_EXTERNAL (decl) = 1;
+
+ /* As a register variable, it has no section. */
return;
- }
+ }
/* Now handle ordinary static variables and functions (in memory).
Also handle vars declared register invalidly. */
else if (name[0] == '*')
@@ -1432,7 +1462,7 @@ make_decl_rtl (tree decl)
#ifdef REGISTER_PREFIX
if (strlen (REGISTER_PREFIX) != 0)
{
- reg_number = decode_reg_name (name);
+ int reg_number = decode_reg_name (name);
if (reg_number >= 0 || reg_number == -3)
error ("register name given for non-register variable %q+D", decl);
}
diff --git a/gcc/varasm.h b/gcc/varasm.h
index 51a5492..042ce1a 100644
--- a/gcc/varasm.h
+++ b/gcc/varasm.h
@@ -79,4 +79,7 @@ extern rtx assemble_static_space (unsigned HOST_WIDE_INT);
extern rtx assemble_trampoline_template (void);
+extern bool register_asmspec_ok_p (tree decl, const char *spec,
+ machine_mode mode, int *regnum = NULL);
+
#endif // GCC_VARASM_H
--
2.7.0
