Commit f4684242 by Jakub Jelinek Committed by Jakub Jelinek

re PR fortran/45636 (Failed to fold simple Fortran string)

	PR fortran/45636
	* tree-ssa-forwprop.c: Include expr.h.
	(constant_pointer_difference, simplify_builtin_call): New functions.
	(tree_ssa_forward_propagate_single_use_vars): Call
	simplify_builtin_call on builtin calls.

	* gcc.c-torture/execute/pr45636.c: New test.
	* gfortran.dg/pr45636.f90: New test.

From-SVN: r165401
parent ad9eef11
2010-10-12 Jakub Jelinek <jakub@redhat.com>
PR fortran/45636
* tree-ssa-forwprop.c: Include expr.h.
(constant_pointer_difference, simplify_builtin_call): New functions.
(tree_ssa_forward_propagate_single_use_vars): Call
simplify_builtin_call on builtin calls.
2010-10-12 Eric Botcazou <ebotcazou@adacore.com> 2010-10-12 Eric Botcazou <ebotcazou@adacore.com>
* config/sparc/sparc.md (*adddi3_insn_sp32): Rename. * config/sparc/sparc.md (*adddi3_insn_sp32): Rename.
...@@ -2408,7 +2408,7 @@ tree-ssa-dse.o : tree-ssa-dse.c $(CONFIG_H) $(SYSTEM_H) coretypes.h \ ...@@ -2408,7 +2408,7 @@ tree-ssa-dse.o : tree-ssa-dse.c $(CONFIG_H) $(SYSTEM_H) coretypes.h \
tree-ssa-forwprop.o : tree-ssa-forwprop.c $(CONFIG_H) $(SYSTEM_H) coretypes.h \ tree-ssa-forwprop.o : tree-ssa-forwprop.c $(CONFIG_H) $(SYSTEM_H) coretypes.h \
$(TM_H) $(TREE_H) $(TM_P_H) $(BASIC_BLOCK_H) \ $(TM_H) $(TREE_H) $(TM_P_H) $(BASIC_BLOCK_H) \
$(TREE_FLOW_H) $(TREE_PASS_H) $(TREE_DUMP_H) $(DIAGNOSTIC_H) $(TIMEVAR_H) \ $(TREE_FLOW_H) $(TREE_PASS_H) $(TREE_DUMP_H) $(DIAGNOSTIC_H) $(TIMEVAR_H) \
langhooks.h $(FLAGS_H) $(GIMPLE_H) tree-pretty-print.h langhooks.h $(FLAGS_H) $(GIMPLE_H) tree-pretty-print.h $(EXPR_H)
tree-ssa-phiprop.o : tree-ssa-phiprop.c $(CONFIG_H) $(SYSTEM_H) coretypes.h \ tree-ssa-phiprop.o : tree-ssa-phiprop.c $(CONFIG_H) $(SYSTEM_H) coretypes.h \
$(TM_H) $(TREE_H) $(TM_P_H) $(BASIC_BLOCK_H) \ $(TM_H) $(TREE_H) $(TM_P_H) $(BASIC_BLOCK_H) \
$(TREE_FLOW_H) $(TREE_PASS_H) $(TREE_DUMP_H) $(DIAGNOSTIC_H) $(TIMEVAR_H) \ $(TREE_FLOW_H) $(TREE_PASS_H) $(TREE_DUMP_H) $(DIAGNOSTIC_H) $(TIMEVAR_H) \
......
2010-10-12 Jakub Jelinek <jakub@redhat.com>
PR fortran/45636
* gcc.c-torture/execute/pr45636.c: New test.
* gfortran.dg/pr45636.f90: New test.
2010-10-12 Richard Henderson <rth@redhat.com> 2010-10-12 Richard Henderson <rth@redhat.com>
* g++.dg/abi/mangle40.C: Robustify tests for defined symbols. * g++.dg/abi/mangle40.C: Robustify tests for defined symbols.
......
/* PR fortran/45636 */
typedef __SIZE_TYPE__ size_t;
void *memcpy (void *__restrict__, const void *__restrict__, size_t);
void *mempcpy (void *__restrict__, const void *__restrict__, size_t);
void *memset (void *, int, size_t);
int memcmp (const void *, const void *, size_t);
extern void abort (void);
struct A { int i; char c[32]; } a[2];
__attribute__((noinline, noclone)) int
f1 (char *p, int q, int z)
{
memcpy (p, "abcd", 4);
if (q)
z = z + 123;
else
z *= 114;
memset (p + 4, ' ', 2);
return z;
}
__attribute__((noinline, noclone)) void
f2 (void)
{
char *p = mempcpy (&a[0].c[13], "123456", 4);
memset (p, '7', 3);
}
__attribute__((noinline, noclone)) void
f3 (struct A *p)
{
p++;
char *q = &p->c[10];
memcpy (q + 4, "__1234567" + 2, 7);
memset (&p->c[21], '9', 3);
}
__attribute__((noinline, noclone)) void
f4 (void)
{
memcpy (&a[0].c[10], "0123456789", 10);
memset (&a[0].c[13], ' ', 3);
}
__attribute__((noinline, noclone)) void
check (const char *p, const char *str, size_t size)
{
const char *q;
for (q = (const char *) &a; q < p; q++)
if (*q)
abort ();
if (memcmp (p, str, size) != 0)
abort ();
for (q = p + size; q < (const char *) (&a[0] + 2); q++)
if (*q)
abort ();
memset (&a, '\0', sizeof a);
}
int
main (void)
{
if (f1 (&a[0].c[7], 1, 2) != 125)
abort ();
check (&a[0].c[7], "abcd ", 6);
f2 ();
check (&a[0].c[13], "1234777", 7);
f3 (&a[0]);
check (&a[1].c[14], "1234567999", 10);
f4 ();
check (&a[0].c[10], "012 6789", 10);
return 0;
}
! PR fortran/45636
! { dg-do compile }
! { dg-options "-O2 -fdump-tree-forwprop2" }
! PR 45636 - make sure no memset is needed for a short right-hand side.
program main
character(len=2), parameter :: x='a '
character(len=1), parameter :: y='b'
character(len=4) :: a, b
a = x
b = y
call sub(a, b)
end program main
! { dg-final { scan-tree-dump-times "memset" 0 "forwprop2" } }
! { dg-final { cleanup-tree-dump "forwprop2" } }
...@@ -33,6 +33,7 @@ along with GCC; see the file COPYING3. If not see ...@@ -33,6 +33,7 @@ along with GCC; see the file COPYING3. If not see
#include "langhooks.h" #include "langhooks.h"
#include "flags.h" #include "flags.h"
#include "gimple.h" #include "gimple.h"
#include "expr.h"
/* This pass propagates the RHS of assignment statements into use /* This pass propagates the RHS of assignment statements into use
sites of the LHS of the assignment. It's basically a specialized sites of the LHS of the assignment. It's basically a specialized
...@@ -1317,6 +1318,299 @@ simplify_gimple_switch (gimple stmt) ...@@ -1317,6 +1318,299 @@ simplify_gimple_switch (gimple stmt)
} }
} }
/* For pointers p2 and p1 return p2 - p1 if the
difference is known and constant, otherwise return NULL. */
static tree
constant_pointer_difference (tree p1, tree p2)
{
int i, j;
#define CPD_ITERATIONS 5
tree exps[2][CPD_ITERATIONS];
tree offs[2][CPD_ITERATIONS];
int cnt[2];
for (i = 0; i < 2; i++)
{
tree p = i ? p1 : p2;
tree off = size_zero_node;
gimple stmt;
enum tree_code code;
/* For each of p1 and p2 we need to iterate at least
twice, to handle ADDR_EXPR directly in p1/p2,
SSA_NAME with ADDR_EXPR or POINTER_PLUS_EXPR etc.
on definition's stmt RHS. Iterate a few extra times. */
j = 0;
do
{
if (!POINTER_TYPE_P (TREE_TYPE (p)))
break;
if (TREE_CODE (p) == ADDR_EXPR)
{
tree q = TREE_OPERAND (p, 0);
HOST_WIDE_INT offset;
tree base = get_addr_base_and_unit_offset (q, &offset);
if (base)
{
q = base;
if (offset)
off = size_binop (PLUS_EXPR, off, size_int (offset));
}
if (TREE_CODE (q) == MEM_REF
&& TREE_CODE (TREE_OPERAND (q, 0)) == SSA_NAME)
{
p = TREE_OPERAND (q, 0);
off = size_binop (PLUS_EXPR, off,
double_int_to_tree (sizetype,
mem_ref_offset (q)));
}
else
{
exps[i][j] = q;
offs[i][j++] = off;
break;
}
}
if (TREE_CODE (p) != SSA_NAME)
break;
exps[i][j] = p;
offs[i][j++] = off;
if (j == CPD_ITERATIONS)
break;
stmt = SSA_NAME_DEF_STMT (p);
if (!is_gimple_assign (stmt) || gimple_assign_lhs (stmt) != p)
break;
code = gimple_assign_rhs_code (stmt);
if (code == POINTER_PLUS_EXPR)
{
if (TREE_CODE (gimple_assign_rhs2 (stmt)) != INTEGER_CST)
break;
off = size_binop (PLUS_EXPR, off, gimple_assign_rhs2 (stmt));
p = gimple_assign_rhs1 (stmt);
}
else if (code == ADDR_EXPR || code == NOP_EXPR)
p = gimple_assign_rhs1 (stmt);
else
break;
}
while (1);
cnt[i] = j;
}
for (i = 0; i < cnt[0]; i++)
for (j = 0; j < cnt[1]; j++)
if (exps[0][i] == exps[1][j])
return size_binop (MINUS_EXPR, offs[0][i], offs[1][j]);
return NULL_TREE;
}
/* *GSI_P is a GIMPLE_CALL to a builtin function.
Optimize
memcpy (p, "abcd", 4);
memset (p + 4, ' ', 3);
into
memcpy (p, "abcd ", 7);
call if the latter can be stored by pieces during expansion. */
static bool
simplify_builtin_call (gimple_stmt_iterator *gsi_p, tree callee2)
{
gimple stmt1, stmt2 = gsi_stmt (*gsi_p);
tree vuse = gimple_vuse (stmt2);
if (vuse == NULL)
return false;
stmt1 = SSA_NAME_DEF_STMT (vuse);
switch (DECL_FUNCTION_CODE (callee2))
{
case BUILT_IN_MEMSET:
if (gimple_call_num_args (stmt2) != 3
|| gimple_call_lhs (stmt2)
|| CHAR_BIT != 8
|| BITS_PER_UNIT != 8)
break;
else
{
tree callee1;
tree ptr1, src1, str1, off1, len1, lhs1;
tree ptr2 = gimple_call_arg (stmt2, 0);
tree val2 = gimple_call_arg (stmt2, 1);
tree len2 = gimple_call_arg (stmt2, 2);
tree diff, vdef, new_str_cst;
gimple use_stmt;
unsigned int ptr1_align;
unsigned HOST_WIDE_INT src_len;
char *src_buf;
use_operand_p use_p;
if (!host_integerp (val2, 0)
|| !host_integerp (len2, 1))
break;
if (is_gimple_call (stmt1))
{
/* If first stmt is a call, it needs to be memcpy
or mempcpy, with string literal as second argument and
constant length. */
callee1 = gimple_call_fndecl (stmt1);
if (callee1 == NULL_TREE
|| DECL_BUILT_IN_CLASS (callee1) != BUILT_IN_NORMAL
|| gimple_call_num_args (stmt1) != 3)
break;
if (DECL_FUNCTION_CODE (callee1) != BUILT_IN_MEMCPY
&& DECL_FUNCTION_CODE (callee1) != BUILT_IN_MEMPCPY)
break;
ptr1 = gimple_call_arg (stmt1, 0);
src1 = gimple_call_arg (stmt1, 1);
len1 = gimple_call_arg (stmt1, 2);
lhs1 = gimple_call_lhs (stmt1);
if (!host_integerp (len1, 1))
break;
str1 = string_constant (src1, &off1);
if (str1 == NULL_TREE)
break;
if (!host_integerp (off1, 1)
|| compare_tree_int (off1, TREE_STRING_LENGTH (str1) - 1) > 0
|| compare_tree_int (len1, TREE_STRING_LENGTH (str1)
- tree_low_cst (off1, 1)) > 0
|| TREE_CODE (TREE_TYPE (str1)) != ARRAY_TYPE
|| TYPE_MODE (TREE_TYPE (TREE_TYPE (str1)))
!= TYPE_MODE (char_type_node))
break;
}
else if (gimple_assign_single_p (stmt1))
{
/* Otherwise look for length 1 memcpy optimized into
assignment. */
ptr1 = gimple_assign_lhs (stmt1);
src1 = gimple_assign_rhs1 (stmt1);
if (TREE_CODE (ptr1) != MEM_REF
|| TYPE_MODE (TREE_TYPE (ptr1)) != TYPE_MODE (char_type_node)
|| !host_integerp (src1, 0))
break;
ptr1 = build_fold_addr_expr (ptr1);
callee1 = NULL_TREE;
len1 = size_one_node;
lhs1 = NULL_TREE;
off1 = size_zero_node;
str1 = NULL_TREE;
}
else
break;
diff = constant_pointer_difference (ptr1, ptr2);
if (diff == NULL && lhs1 != NULL)
{
diff = constant_pointer_difference (lhs1, ptr2);
if (DECL_FUNCTION_CODE (callee1) == BUILT_IN_MEMPCPY
&& diff != NULL)
diff = size_binop (PLUS_EXPR, diff,
fold_convert (sizetype, len1));
}
/* If the difference between the second and first destination pointer
is not constant, or is bigger than memcpy length, bail out. */
if (diff == NULL
|| !host_integerp (diff, 1)
|| tree_int_cst_lt (len1, diff))
break;
/* Use maximum of difference plus memset length and memcpy length
as the new memcpy length, if it is too big, bail out. */
src_len = tree_low_cst (diff, 1);
src_len += tree_low_cst (len2, 1);
if (src_len < (unsigned HOST_WIDE_INT) tree_low_cst (len1, 1))
src_len = tree_low_cst (len1, 1);
if (src_len > 1024)
break;
/* If mempcpy value is used elsewhere, bail out, as mempcpy
with bigger length will return different result. */
if (lhs1 != NULL_TREE
&& DECL_FUNCTION_CODE (callee1) == BUILT_IN_MEMPCPY
&& (TREE_CODE (lhs1) != SSA_NAME
|| !single_imm_use (lhs1, &use_p, &use_stmt)
|| use_stmt != stmt2))
break;
/* If anything reads memory in between memcpy and memset
call, the modified memcpy call might change it. */
vdef = gimple_vdef (stmt1);
if (vdef != NULL
&& (!single_imm_use (vdef, &use_p, &use_stmt)
|| use_stmt != stmt2))
break;
ptr1_align = get_pointer_alignment (ptr1, BIGGEST_ALIGNMENT);
/* Construct the new source string literal. */
src_buf = XALLOCAVEC (char, src_len + 1);
if (callee1)
memcpy (src_buf,
TREE_STRING_POINTER (str1) + tree_low_cst (off1, 1),
tree_low_cst (len1, 1));
else
src_buf[0] = tree_low_cst (src1, 0);
memset (src_buf + tree_low_cst (diff, 1),
tree_low_cst (val2, 1), tree_low_cst (len2, 1));
src_buf[src_len] = '\0';
/* Neither builtin_strncpy_read_str nor builtin_memcpy_read_str
handle embedded '\0's. */
if (strlen (src_buf) != src_len)
break;
rtl_profile_for_bb (gimple_bb (stmt2));
/* If the new memcpy wouldn't be emitted by storing the literal
by pieces, this optimization might enlarge .rodata too much,
as commonly used string literals couldn't be shared any
longer. */
if (!can_store_by_pieces (src_len,
builtin_strncpy_read_str,
src_buf, ptr1_align, false))
break;
new_str_cst = build_string_literal (src_len, src_buf);
if (callee1)
{
/* If STMT1 is a mem{,p}cpy call, adjust it and remove
memset call. */
if (lhs1 && DECL_FUNCTION_CODE (callee1) == BUILT_IN_MEMPCPY)
gimple_call_set_lhs (stmt1, NULL_TREE);
gimple_call_set_arg (stmt1, 1, new_str_cst);
gimple_call_set_arg (stmt1, 2,
build_int_cst (TREE_TYPE (len1), src_len));
update_stmt (stmt1);
unlink_stmt_vdef (stmt2);
gsi_remove (gsi_p, true);
release_defs (stmt2);
if (lhs1 && DECL_FUNCTION_CODE (callee1) == BUILT_IN_MEMPCPY)
release_ssa_name (lhs1);
return true;
}
else
{
/* Otherwise, if STMT1 is length 1 memcpy optimized into
assignment, remove STMT1 and change memset call into
memcpy call. */
gimple_stmt_iterator gsi = gsi_for_stmt (stmt1);
gimple_call_set_fndecl (stmt2, built_in_decls [BUILT_IN_MEMCPY]);
gimple_call_set_arg (stmt2, 0, ptr1);
gimple_call_set_arg (stmt2, 1, new_str_cst);
gimple_call_set_arg (stmt2, 2,
build_int_cst (TREE_TYPE (len2), src_len));
unlink_stmt_vdef (stmt1);
gsi_remove (&gsi, true);
release_defs (stmt1);
update_stmt (stmt2);
return false;
}
}
break;
default:
break;
}
return false;
}
/* Run bitwise and assignments throug the folder. If the first argument is an /* Run bitwise and assignments throug the folder. If the first argument is an
ssa name that is itself a result of a typecast of an ADDR_EXPR to an ssa name that is itself a result of a typecast of an ADDR_EXPR to an
integer, feed the ADDR_EXPR to the folder rather than the ssa name. integer, feed the ADDR_EXPR to the folder rather than the ssa name.
...@@ -1784,6 +2078,14 @@ tree_ssa_forward_propagate_single_use_vars (void) ...@@ -1784,6 +2078,14 @@ tree_ssa_forward_propagate_single_use_vars (void)
WARN_STRICT_OVERFLOW_CONDITIONAL); WARN_STRICT_OVERFLOW_CONDITIONAL);
gsi_next (&gsi); gsi_next (&gsi);
} }
else if (is_gimple_call (stmt))
{
tree callee = gimple_call_fndecl (stmt);
if (callee == NULL_TREE
|| DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL
|| !simplify_builtin_call (&gsi, callee))
gsi_next (&gsi);
}
else else
gsi_next (&gsi); gsi_next (&gsi);
} }
......
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