|| TREE_CODE (base) == MEM_REF)
&& TREE_CODE (TREE_OPERAND (base, 0)) != SSA_NAME)
return false;
+ if (TREE_CODE (base) == TARGET_MEM_REF
+ && TMR_BASE (base)
+ && TREE_CODE (TMR_BASE (base)) != SSA_NAME)
+ return false;
/* If this is a reference based on a partitioned decl replace the
base with an INDIRECT_REF of the pointer representative we
if (namep)
ref->base = build_simple_mem_ref (*(tree *)namep);
}
+ else if (TREE_CODE (base) == TARGET_MEM_REF
+ && TREE_CODE (TMR_BASE (base)) == ADDR_EXPR
+ && TREE_CODE (TREE_OPERAND (TMR_BASE (base), 0)) == VAR_DECL
+ && ! TREE_STATIC (TREE_OPERAND (TMR_BASE (base), 0))
+ && cfun->gimple_df->decls_to_pointers != NULL)
+ {
+ void *namep;
+ namep = pointer_map_contains (cfun->gimple_df->decls_to_pointers,
+ TREE_OPERAND (TMR_BASE (base), 0));
+ if (namep)
+ ref->base = build_simple_mem_ref (*(tree *)namep);
+ }
ref->ref_alias_set = MEM_ALIAS_SET (mem);
return 0;
}
-static int
-walk_mems_2 (rtx *x, rtx mem)
-{
- if (MEM_P (*x))
- {
- if (alias_sets_conflict_p (MEM_ALIAS_SET(*x), MEM_ALIAS_SET(mem)))
- return 1;
-
- return -1;
- }
- return 0;
-}
-
-static int
-walk_mems_1 (rtx *x, rtx *pat)
-{
- if (MEM_P (*x))
- {
- /* Visit all MEMs in *PAT and check indepedence. */
- if (for_each_rtx (pat, (rtx_function) walk_mems_2, *x))
- /* Indicate that dependence was determined and stop traversal. */
- return 1;
-
- return -1;
- }
- return 0;
-}
-
-/* Return 1 if two specified instructions have mem expr with conflict alias sets*/
-bool
-insn_alias_sets_conflict_p (rtx insn1, rtx insn2)
-{
- /* For each pair of MEMs in INSN1 and INSN2 check their independence. */
- return for_each_rtx (&PATTERN (insn1), (rtx_function) walk_mems_1,
- &PATTERN (insn2));
-}
-
/* Return 1 if the two specified alias sets will always conflict. */
int
if (set != -1)
return set;
- /* Retrieve the original memory reference if needed. */
- if (TREE_CODE (t) == TARGET_MEM_REF)
- t = TMR_ORIGINAL (t);
-
/* Get the base object of the reference. */
inner = t;
while (handled_component_p (inner))
if (set != -1)
return set;
}
+ else if (TREE_CODE (inner) == TARGET_MEM_REF)
+ return get_deref_alias_set (TMR_OFFSET (inner));
else if (TREE_CODE (inner) == MEM_REF)
{
set = get_deref_alias_set_1 (TREE_OPERAND (inner, 1));
else if (TREE_CODE (t) == ARRAY_TYPE && !TYPE_NONALIASED_COMPONENT (t))
set = get_alias_set (TREE_TYPE (t));
+ /* From the former common C and C++ langhook implementation:
+
+ Unfortunately, there is no canonical form of a pointer type.
+ In particular, if we have `typedef int I', then `int *', and
+ `I *' are different types. So, we have to pick a canonical
+ representative. We do this below.
+
+ Technically, this approach is actually more conservative that
+ it needs to be. In particular, `const int *' and `int *'
+ should be in different alias sets, according to the C and C++
+ standard, since their types are not the same, and so,
+ technically, an `int **' and `const int **' cannot point at
+ the same thing.
+
+ But, the standard is wrong. In particular, this code is
+ legal C++:
+
+ int *ip;
+ int **ipp = &ip;
+ const int* const* cipp = ipp;
+ And, it doesn't make sense for that to be legal unless you
+ can dereference IPP and CIPP. So, we ignore cv-qualifiers on
+ the pointed-to types. This issue has been reported to the
+ C++ committee.
+
+ In addition to the above canonicalization issue, with LTO
+ we should also canonicalize `T (*)[]' to `T *' avoiding
+ alias issues with pointer-to element types and pointer-to
+ array types.
+
+ Likewise we need to deal with the situation of incomplete
+ pointed-to types and make `*(struct X **)&a' and
+ `*(struct X {} **)&a' alias. Otherwise we will have to
+ guarantee that all pointer-to incomplete type variants
+ will be replaced by pointer-to complete type variants if
+ they are available.
+
+ With LTO the convenient situation of using `void *' to
+ access and store any pointer type will also become
+ more apparent (and `void *' is just another pointer-to
+ incomplete type). Assigning alias-set zero to `void *'
+ and all pointer-to incomplete types is a not appealing
+ solution. Assigning an effective alias-set zero only
+ affecting pointers might be - by recording proper subset
+ relationships of all pointer alias-sets.
+
+ Pointer-to function types are another grey area which
+ needs caution. Globbing them all into one alias-set
+ or the above effective zero set would work.
+
+ For now just assign the same alias-set to all pointers.
+ That's simple and avoids all the above problems. */
+ else if (POINTER_TYPE_P (t)
+ && t != ptr_type_node)
+ return get_alias_set (ptr_type_node);
+
/* Otherwise make a new alias set for this type. */
else
set = new_alias_set ();
reg_seen[regno] = 1;
}
+/* Return REG_BASE_VALUE for REGNO. Selective scheduler uses this to avoid
+ using hard registers with non-null REG_BASE_VALUE for renaming. */
+rtx
+get_reg_base_value (unsigned int regno)
+{
+ return VEC_index (rtx, reg_base_value, regno);
+}
+
/* If a value is known for REGNO, return it. */
rtx
}
/* Return nonzero if we can determine the exprs corresponding to memrefs
- X and Y and they do not overlap. */
+ X and Y and they do not overlap.
+ If LOOP_VARIANT is set, skip offset-based disambiguation */
int
-nonoverlapping_memrefs_p (const_rtx x, const_rtx y)
+nonoverlapping_memrefs_p (const_rtx x, const_rtx y, bool loop_invariant)
{
tree exprx = MEM_EXPR (x), expry = MEM_EXPR (y);
rtx rtlx, rtly;
|| (CONSTANT_P (basey) && REG_P (basex)
&& REGNO_PTR_FRAME_P (REGNO (basex))));
+ /* Offset based disambiguation not appropriate for loop invariant */
+ if (loop_invariant)
+ return 0;
+
sizex = (!MEM_P (rtlx) ? (int) GET_MODE_SIZE (GET_MODE (rtlx))
: MEM_SIZE (rtlx) ? INTVAL (MEM_SIZE (rtlx))
: -1);
if (DIFFERENT_ALIAS_SETS_P (x, mem))
return 0;
- if (nonoverlapping_memrefs_p (mem, x))
+ if (nonoverlapping_memrefs_p (mem, x, false))
return 0;
if (aliases_everything_p (x))
/* We cannot use aliases_everything_p to test MEM, since we must look
at MEM_ADDR, rather than XEXP (mem, 0). */
- if (mem_mode == QImode || GET_CODE (mem_addr) == AND)
+ if (GET_CODE (mem_addr) == AND)
return 1;
/* ??? In true_dependence we also allow BLKmode to alias anything. Why
SIZE_FOR_MODE (x), x_addr, 0)) != -1)
return ret;
- if (nonoverlapping_memrefs_p (x, mem))
+ if (nonoverlapping_memrefs_p (x, mem, false))
return 0;
fixed_scalar
}
\f
+
+/* Check whether X may be aliased with MEM. Don't do offset-based
+ memory disambiguation & TBAA. */
+int
+may_alias_p (const_rtx mem, const_rtx x)
+{
+ rtx x_addr, mem_addr;
+
+ if (MEM_VOLATILE_P (x) && MEM_VOLATILE_P (mem))
+ return 1;
+
+ /* ??? In true_dependence we also allow BLKmode to alias anything. */
+ if (GET_MODE (mem) == BLKmode || GET_MODE (x) == BLKmode)
+ return 1;
+
+ if (MEM_ALIAS_SET (x) == ALIAS_SET_MEMORY_BARRIER
+ || MEM_ALIAS_SET (mem) == ALIAS_SET_MEMORY_BARRIER)
+ return 1;
+
+ /* Read-only memory is by definition never modified, and therefore can't
+ conflict with anything. We don't expect to find read-only set on MEM,
+ but stupid user tricks can produce them, so don't die. */
+ if (MEM_READONLY_P (x))
+ return 0;
+
+ /* If we have MEMs refering to different address spaces (which can
+ potentially overlap), we cannot easily tell from the addresses
+ whether the references overlap. */
+ if (MEM_ADDR_SPACE (mem) != MEM_ADDR_SPACE (x))
+ return 1;
+
+ x_addr = XEXP (x, 0);
+ mem_addr = XEXP (mem, 0);
+ if (!((GET_CODE (x_addr) == VALUE
+ && GET_CODE (mem_addr) != VALUE
+ && reg_mentioned_p (x_addr, mem_addr))
+ || (GET_CODE (x_addr) != VALUE
+ && GET_CODE (mem_addr) == VALUE
+ && reg_mentioned_p (mem_addr, x_addr))))
+ {
+ x_addr = get_addr (x_addr);
+ mem_addr = get_addr (mem_addr);
+ }
+
+ if (! base_alias_check (x_addr, mem_addr, GET_MODE (x), GET_MODE (mem_addr)))
+ return 0;
+
+ x_addr = canon_rtx (x_addr);
+ mem_addr = canon_rtx (mem_addr);
+
+ if (nonoverlapping_memrefs_p (mem, x, true))
+ return 0;
+
+ if (aliases_everything_p (x))
+ return 1;
+
+ /* We cannot use aliases_everything_p to test MEM, since we must look
+ at MEM_ADDR, rather than XEXP (mem, 0). */
+ if (GET_CODE (mem_addr) == AND)
+ return 1;
+
+ if (fixed_scalar_and_varying_struct_p (mem, x, mem_addr, x_addr,
+ rtx_addr_varies_p))
+ return 0;
+
+ /* TBAA not valid for loop_invarint */
+ return rtx_refs_may_alias_p (x, mem, false);
+}
+
void
init_alias_target (void)
{
= gen_rtx_ADDRESS (Pmode, arg_pointer_rtx);
static_reg_base_value[FRAME_POINTER_REGNUM]
= gen_rtx_ADDRESS (Pmode, frame_pointer_rtx);
-#if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
+#if !HARD_FRAME_POINTER_IS_FRAME_POINTER
static_reg_base_value[HARD_FRAME_POINTER_REGNUM]
= gen_rtx_ADDRESS (Pmode, hard_frame_pointer_rtx);
#endif
timevar_pop (TV_ALIAS_ANALYSIS);
}
+/* Equate REG_BASE_VALUE (reg1) to REG_BASE_VALUE (reg2).
+ Special API for var-tracking pass purposes. */
+
+void
+vt_equate_reg_base_value (const_rtx reg1, const_rtx reg2)
+{
+ VEC_replace (rtx, reg_base_value, REGNO (reg1), REG_BASE_VALUE (reg2));
+}
+
void
end_alias_analysis (void)
{
OSDN Git Service
