diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ssa-ccp-44.c b/gcc/testsuite/gcc.dg/tree-ssa/ssa-ccp-44.c new file mode 100644 index 0000000000000000000000000000000000000000..f1f09bfb11701b0c82b0be599a4e998f1c2f0422 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/ssa-ccp-44.c @@ -0,0 +1,13 @@ +/* { dg-do compile } */ +/* { dg-options "-O -fdump-tree-ccp1" } */ + +int +test(int* a, int* b) +{ + __INTPTR_TYPE__ delta = (int*)__builtin_assume_aligned(b, 32) + - (int*)__builtin_assume_aligned(a, 32); + __INTPTR_TYPE__ x = delta % 8; + return (x == 0); +} + +/* { dg-final { scan-tree-dump "return 1;" "ccp1" } } */ diff --git a/gcc/tree-ssa-ccp.cc b/gcc/tree-ssa-ccp.cc index 47b2ce9441e53d54aa04037675fdc929362f0afc..a5f6ef5f5ddd12a6181d714d4ff12720206e2dca 100644 --- a/gcc/tree-ssa-ccp.cc +++ b/gcc/tree-ssa-ccp.cc @@ -1921,6 +1921,27 @@ bit_value_binop (enum tree_code code, signop sgn, int width, { widest_int r1max = r1val | r1mask; widest_int r2max = r2val | r2mask; + if (r2mask == 0) + { + widest_int shift = wi::exact_log2 (r2val); + if (shift != -1) + { + // Handle modulo by a power of 2 as a bitwise and. + widest_int tem_val, tem_mask; + bit_value_binop (BIT_AND_EXPR, sgn, width, &tem_val, &tem_mask, + r1type_sgn, r1type_precision, r1val, r1mask, + r2type_sgn, r2type_precision, + r2val - 1, r2mask); + if (sgn == UNSIGNED + || !wi::neg_p (r1max) + || (tem_mask == 0 && tem_val == 0)) + { + *val = tem_val; + *mask = tem_mask; + return; + } + } + } if (sgn == UNSIGNED || (!wi::neg_p (r1max) && !wi::neg_p (r2max))) { @@ -1949,11 +1970,15 @@ bit_value_binop (enum tree_code code, signop sgn, int width, } break; + case EXACT_DIV_EXPR: case TRUNC_DIV_EXPR: { widest_int r1max = r1val | r1mask; widest_int r2max = r2val | r2mask; - if (r2mask == 0 && !wi::neg_p (r1max)) + if (r2mask == 0 + && (code == EXACT_DIV_EXPR + || sgn == UNSIGNED + || !wi::neg_p (r1max))) { widest_int shift = wi::exact_log2 (r2val); if (shift != -1)