diff options
Diffstat (limited to 'gcc/emit-rtl.c')
| -rw-r--r-- | gcc/emit-rtl.c | 112 |
1 files changed, 92 insertions, 20 deletions
diff --git a/gcc/emit-rtl.c b/gcc/emit-rtl.c index e7afacd8a4e..d25e5496c88 100644 --- a/gcc/emit-rtl.c +++ b/gcc/emit-rtl.c @@ -195,6 +195,7 @@ static void mem_attrs_mark PARAMS ((const void *)); static mem_attrs *get_mem_attrs PARAMS ((HOST_WIDE_INT, tree, rtx, rtx, unsigned int, enum machine_mode)); +static tree component_ref_for_mem_expr PARAMS ((tree)); /* Probability of the conditional branch currently proceeded by try_split. Set to -1 otherwise. */ @@ -232,7 +233,7 @@ mem_attrs_htab_hash (x) return (p->alias ^ (p->align * 1000) ^ ((p->offset ? INTVAL (p->offset) : 0) * 50000) ^ ((p->size ? INTVAL (p->size) : 0) * 2500000) - ^ (long) p->decl); + ^ (size_t) p->expr); } /* Returns non-zero if the value represented by X (which is really a @@ -247,7 +248,7 @@ mem_attrs_htab_eq (x, y) mem_attrs *p = (mem_attrs *) x; mem_attrs *q = (mem_attrs *) y; - return (p->alias == q->alias && p->decl == q->decl && p->offset == q->offset + return (p->alias == q->alias && p->expr == q->expr && p->offset == q->offset && p->size == q->size && p->align == q->align); } @@ -260,8 +261,8 @@ mem_attrs_mark (x) { mem_attrs *p = (mem_attrs *) x; - if (p->decl) - ggc_mark_tree (p->decl); + if (p->expr) + ggc_mark_tree (p->expr); if (p->offset) ggc_mark_rtx (p->offset); @@ -275,9 +276,9 @@ mem_attrs_mark (x) MEM of mode MODE. */ static mem_attrs * -get_mem_attrs (alias, decl, offset, size, align, mode) +get_mem_attrs (alias, expr, offset, size, align, mode) HOST_WIDE_INT alias; - tree decl; + tree expr; rtx offset; rtx size; unsigned int align; @@ -287,7 +288,7 @@ get_mem_attrs (alias, decl, offset, size, align, mode) void **slot; /* If everything is the default, we can just return zero. */ - if (alias == 0 && decl == 0 && offset == 0 + if (alias == 0 && expr == 0 && offset == 0 && (size == 0 || (mode != BLKmode && GET_MODE_SIZE (mode) == INTVAL (size))) && (align == BITS_PER_UNIT @@ -295,7 +296,7 @@ get_mem_attrs (alias, decl, offset, size, align, mode) return 0; attrs.alias = alias; - attrs.decl = decl; + attrs.expr = expr; attrs.offset = offset; attrs.size = size; attrs.align = align; @@ -1636,6 +1637,26 @@ reverse_comparison (insn) } } +/* Within a MEM_EXPR, we care about either (1) a component ref of a decl, + or (2) a component ref of something variable. Represent the later with + a NULL expression. */ + +static tree +component_ref_for_mem_expr (ref) + tree ref; +{ + tree inner = TREE_OPERAND (ref, 0); + + if (TREE_CODE (inner) == COMPONENT_REF) + inner = component_ref_for_mem_expr (inner); + else if (! DECL_P (inner)) + inner = NULL_TREE; + + if (inner == TREE_OPERAND (ref, 0)) + return ref; + else + return build (COMPONENT_REF, TREE_TYPE (ref), inner, TREE_OPERAND (ref, 1)); +} /* Given REF, a MEM, and T, either the type of X or the expression corresponding to REF, set the memory attributes. OBJECTP is nonzero @@ -1648,7 +1669,7 @@ set_mem_attributes (ref, t, objectp) int objectp; { HOST_WIDE_INT alias = MEM_ALIAS_SET (ref); - tree decl = MEM_DECL (ref); + tree expr = MEM_EXPR (ref); rtx offset = MEM_OFFSET (ref); rtx size = MEM_SIZE (ref); unsigned int align = MEM_ALIGN (ref); @@ -1716,8 +1737,8 @@ set_mem_attributes (ref, t, objectp) /* If this is a decl, set the attributes of the MEM from it. */ if (DECL_P (t)) { - decl = t; - offset = GEN_INT (0); + expr = t; + offset = const0_rtx; size = (DECL_SIZE_UNIT (t) && host_integerp (DECL_SIZE_UNIT (t), 1) ? GEN_INT (tree_low_cst (DECL_SIZE_UNIT (t), 1)) : 0); @@ -1732,11 +1753,51 @@ set_mem_attributes (ref, t, objectp) align = CONSTANT_ALIGNMENT (t, align); #endif } + + /* If this is a field reference and not a bit-field, record it. */ + /* ??? There is some information that can be gleened from bit-fields, + such as the word offset in the structure that might be modified. + But skip it for now. */ + else if (TREE_CODE (t) == COMPONENT_REF + && ! DECL_BIT_FIELD (TREE_OPERAND (t, 1))) + { + expr = component_ref_for_mem_expr (t); + offset = const0_rtx; + /* ??? Any reason the field size would be different than + the size we got from the type? */ + } + + /* If this is an array reference, look for an outer field reference. */ + else if (TREE_CODE (t) == ARRAY_REF) + { + tree off_tree = size_zero_node; + + do + { + off_tree + = fold (build (PLUS_EXPR, sizetype, + fold (build (MULT_EXPR, sizetype, + TREE_OPERAND (t, 1), + TYPE_SIZE_UNIT (TREE_TYPE (t)))), + off_tree)); + t = TREE_OPERAND (t, 0); + } + while (TREE_CODE (t) == ARRAY_REF); + + if (TREE_CODE (t) == COMPONENT_REF) + { + expr = component_ref_for_mem_expr (t); + if (host_integerp (off_tree, 1)) + offset = GEN_INT (tree_low_cst (off_tree, 1)); + /* ??? Any reason the field size would be different than + the size we got from the type? */ + } + } } /* Now set the attributes we computed above. */ MEM_ATTRS (ref) - = get_mem_attrs (alias, decl, offset, size, align, GET_MODE (ref)); + = get_mem_attrs (alias, expr, offset, size, align, GET_MODE (ref)); /* If this is already known to be a scalar or aggregate, we are done. */ if (MEM_IN_STRUCT_P (ref) || MEM_SCALAR_P (ref)) @@ -1763,7 +1824,7 @@ set_mem_alias_set (mem, set) abort (); #endif - MEM_ATTRS (mem) = get_mem_attrs (set, MEM_DECL (mem), MEM_OFFSET (mem), + MEM_ATTRS (mem) = get_mem_attrs (set, MEM_EXPR (mem), MEM_OFFSET (mem), MEM_SIZE (mem), MEM_ALIGN (mem), GET_MODE (mem)); } @@ -1775,22 +1836,33 @@ set_mem_align (mem, align) rtx mem; unsigned int align; { - MEM_ATTRS (mem) = get_mem_attrs (MEM_ALIAS_SET (mem), MEM_DECL (mem), + MEM_ATTRS (mem) = get_mem_attrs (MEM_ALIAS_SET (mem), MEM_EXPR (mem), MEM_OFFSET (mem), MEM_SIZE (mem), align, GET_MODE (mem)); } -/* Set the decl for MEM to DECL. */ +/* Set the expr for MEM to EXPR. */ void -set_mem_decl (mem, decl) +set_mem_expr (mem, expr) rtx mem; - tree decl; + tree expr; { MEM_ATTRS (mem) - = get_mem_attrs (MEM_ALIAS_SET (mem), decl, MEM_OFFSET (mem), + = get_mem_attrs (MEM_ALIAS_SET (mem), expr, MEM_OFFSET (mem), MEM_SIZE (mem), MEM_ALIGN (mem), GET_MODE (mem)); } + +/* Set the offset of MEM to OFFSET. */ + +void +set_mem_offset (mem, offset) + rtx mem, offset; +{ + MEM_ATTRS (mem) = get_mem_attrs (MEM_ALIAS_SET (mem), MEM_EXPR (mem), + offset, MEM_SIZE (mem), MEM_ALIGN (mem), + GET_MODE (mem)); +} /* Return a memory reference like MEMREF, but with its mode changed to MODE and its address changed to ADDR. (VOIDmode means don't change the mode. @@ -1907,7 +1979,7 @@ adjust_address_1 (memref, mode, offset, validate, adjust) else if (MEM_SIZE (memref)) size = plus_constant (MEM_SIZE (memref), -offset); - MEM_ATTRS (new) = get_mem_attrs (MEM_ALIAS_SET (memref), MEM_DECL (memref), + MEM_ATTRS (new) = get_mem_attrs (MEM_ALIAS_SET (memref), MEM_EXPR (memref), memoffset, size, memalign, GET_MODE (new)); /* At some point, we should validate that this offset is within the object, @@ -1948,7 +2020,7 @@ offset_address (memref, offset, pow2) /* Update the alignment to reflect the offset. Reset the offset, which we don't know. */ - MEM_ATTRS (new) = get_mem_attrs (MEM_ALIAS_SET (memref), MEM_DECL (memref), + MEM_ATTRS (new) = get_mem_attrs (MEM_ALIAS_SET (memref), MEM_EXPR (memref), 0, 0, MIN (MEM_ALIGN (memref), pow2 * BITS_PER_UNIT), GET_MODE (new)); |