diff options
Diffstat (limited to 'gcc/tree-dfa.c')
| -rw-r--r-- | gcc/tree-dfa.c | 122 |
1 files changed, 122 insertions, 0 deletions
diff --git a/gcc/tree-dfa.c b/gcc/tree-dfa.c index 6d016fd3b52..467a6781d7c 100644 --- a/gcc/tree-dfa.c +++ b/gcc/tree-dfa.c @@ -23,6 +23,7 @@ along with GCC; see the file COPYING3. If not see #include "system.h" #include "coretypes.h" #include "tm.h" +#include "toplev.h" #include "hashtab.h" #include "pointer-set.h" #include "tree.h" @@ -855,6 +856,29 @@ get_ref_base_and_extent (tree exp, HOST_WIDE_INT *poffset, case VIEW_CONVERT_EXPR: break; + case MEM_REF: + /* Hand back the decl for MEM[&decl, off]. */ + if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR) + { + if (integer_zerop (TREE_OPERAND (exp, 1))) + exp = TREE_OPERAND (TREE_OPERAND (exp, 0), 0); + else + { + double_int off = mem_ref_offset (exp); + off = double_int_lshift (off, + BITS_PER_UNIT == 8 + ? 3 : exact_log2 (BITS_PER_UNIT), + HOST_BITS_PER_DOUBLE_INT, true); + off = double_int_add (off, shwi_to_double_int (bit_offset)); + if (double_int_fits_in_shwi_p (off)) + { + bit_offset = double_int_to_shwi (off); + exp = TREE_OPERAND (TREE_OPERAND (exp, 0), 0); + } + } + } + goto done; + default: goto done; } @@ -901,6 +925,104 @@ get_ref_base_and_extent (tree exp, HOST_WIDE_INT *poffset, return exp; } +/* Returns the base object and a constant BITS_PER_UNIT offset in *POFFSET that + denotes the starting address of the memory access EXP. + Returns NULL_TREE if the offset is not constant or any component + is not BITS_PER_UNIT-aligned. */ + +tree +get_addr_base_and_unit_offset (tree exp, HOST_WIDE_INT *poffset) +{ + HOST_WIDE_INT byte_offset = 0; + + /* Compute cumulative byte-offset for nested component-refs and array-refs, + and find the ultimate containing object. */ + while (1) + { + switch (TREE_CODE (exp)) + { + case BIT_FIELD_REF: + return NULL_TREE; + + case COMPONENT_REF: + { + tree field = TREE_OPERAND (exp, 1); + tree this_offset = component_ref_field_offset (exp); + HOST_WIDE_INT hthis_offset; + + if (!this_offset + || TREE_CODE (this_offset) != INTEGER_CST + || (TREE_INT_CST_LOW (DECL_FIELD_BIT_OFFSET (field)) + % BITS_PER_UNIT)) + return NULL_TREE; + + hthis_offset = TREE_INT_CST_LOW (this_offset); + hthis_offset += (TREE_INT_CST_LOW (DECL_FIELD_BIT_OFFSET (field)) + / BITS_PER_UNIT); + byte_offset += hthis_offset; + } + break; + + case ARRAY_REF: + case ARRAY_RANGE_REF: + { + tree index = TREE_OPERAND (exp, 1); + tree low_bound, unit_size; + + /* If the resulting bit-offset is constant, track it. */ + if (TREE_CODE (index) == INTEGER_CST + && (low_bound = array_ref_low_bound (exp), + TREE_CODE (low_bound) == INTEGER_CST) + && (unit_size = array_ref_element_size (exp), + TREE_CODE (unit_size) == INTEGER_CST)) + { + HOST_WIDE_INT hindex = TREE_INT_CST_LOW (index); + + hindex -= TREE_INT_CST_LOW (low_bound); + hindex *= TREE_INT_CST_LOW (unit_size); + byte_offset += hindex; + } + else + return NULL_TREE; + } + break; + + case REALPART_EXPR: + break; + + case IMAGPART_EXPR: + byte_offset += TREE_INT_CST_LOW (TYPE_SIZE_UNIT (TREE_TYPE (exp))); + break; + + case VIEW_CONVERT_EXPR: + break; + + case MEM_REF: + /* Hand back the decl for MEM[&decl, off]. */ + if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR) + { + if (!integer_zerop (TREE_OPERAND (exp, 1))) + { + double_int off = mem_ref_offset (exp); + gcc_assert (off.high == -1 || off.high == 0); + byte_offset += double_int_to_shwi (off); + } + exp = TREE_OPERAND (TREE_OPERAND (exp, 0), 0); + } + goto done; + + default: + goto done; + } + + exp = TREE_OPERAND (exp, 0); + } +done: + + *poffset = byte_offset; + return exp; +} + /* Returns true if STMT references an SSA_NAME that has SSA_NAME_OCCURS_IN_ABNORMAL_PHI set, otherwise false. */ |