diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/hwint.h | 42 | ||||
| -rw-r--r-- | gcc/tree-data-ref.c | 63 |
2 files changed, 91 insertions, 14 deletions
diff --git a/gcc/hwint.h b/gcc/hwint.h index 127b013..0e895f8 100644 --- a/gcc/hwint.h +++ b/gcc/hwint.h @@ -333,4 +333,46 @@ absu_hwi (HOST_WIDE_INT x) return x >= 0 ? (unsigned HOST_WIDE_INT)x : -(unsigned HOST_WIDE_INT)x; } +/* Compute the sum of signed A and B and indicate in *OVERFLOW whether + that operation overflowed. */ + +inline HOST_WIDE_INT +add_hwi (HOST_WIDE_INT a, HOST_WIDE_INT b, bool *overflow) +{ +#if GCC_VERSION < 11000 + unsigned HOST_WIDE_INT result = a + (unsigned HOST_WIDE_INT)b; + if ((((result ^ a) & (result ^ b)) + >> (HOST_BITS_PER_WIDE_INT - 1)) & 1) + *overflow = true; + else + *overflow = false; + return result; +#else + HOST_WIDE_INT result; + *overflow = __builtin_add_overflow (a, b, &result); + return result; +#endif +} + +/* Compute the product of signed A and B and indicate in *OVERFLOW whether + that operation overflowed. */ + +inline HOST_WIDE_INT +mul_hwi (HOST_WIDE_INT a, HOST_WIDE_INT b, bool *overflow) +{ +#if GCC_VERSION < 11000 + unsigned HOST_WIDE_INT result = a * (unsigned HOST_WIDE_INT)b; + if ((a == -1 && b == HOST_WIDE_INT_MIN) + || (a != 0 && (HOST_WIDE_INT)result / a != b)) + *overflow = true; + else + *overflow = false; + return result; +#else + HOST_WIDE_INT result; + *overflow = __builtin_mul_overflow (a, b, &result); + return result; +#endif +} + #endif /* ! GCC_HWINT_H */ diff --git a/gcc/tree-data-ref.c b/gcc/tree-data-ref.c index 9d07b41..d19c5eb 100644 --- a/gcc/tree-data-ref.c +++ b/gcc/tree-data-ref.c @@ -3924,9 +3924,25 @@ initialize_matrix_A (lambda_matrix A, tree chrec, unsigned index, int mult) switch (TREE_CODE (chrec)) { case POLYNOMIAL_CHREC: - if (!cst_and_fits_in_hwi (CHREC_RIGHT (chrec))) + /* CHREC_RIGHT and its negated value should fit in a lambda_int. + Pointer typed chrecs right are to be interpreted signed. */ + HOST_WIDE_INT chrec_right; + if (POINTER_TYPE_P (chrec_type (chrec))) + { + if (!cst_and_fits_in_hwi (CHREC_RIGHT (chrec))) + return chrec_dont_know; + chrec_right = int_cst_value (CHREC_RIGHT (chrec)); + } + else + { + if (!tree_fits_shwi_p (CHREC_RIGHT (chrec))) + return chrec_dont_know; + chrec_right = tree_to_shwi (CHREC_RIGHT (chrec)); + } + /* We want to be able to negate without overflow. */ + if (chrec_right == HOST_WIDE_INT_MIN) return chrec_dont_know; - A[index][0] = mult * int_cst_value (CHREC_RIGHT (chrec)); + A[index][0] = mult * chrec_right; return initialize_matrix_A (A, CHREC_LEFT (chrec), index + 1, mult); case PLUS_EXPR: @@ -4193,17 +4209,28 @@ lambda_vector_first_nz (lambda_vector vec1, int n, int start) /* Add a multiple of row R1 of matrix MAT with N columns to row R2: R2 = R2 + CONST1 * R1. */ -static void +static bool lambda_matrix_row_add (lambda_matrix mat, int n, int r1, int r2, lambda_int const1) { int i; if (const1 == 0) - return; + return true; for (i = 0; i < n; i++) - mat[r2][i] += const1 * mat[r1][i]; + { + bool ovf; + lambda_int tem = mul_hwi (mat[r1][i], const1, &ovf); + if (ovf) + return false; + lambda_int tem2 = add_hwi (mat[r2][i], tem, &ovf); + if (ovf || tem2 == HOST_WIDE_INT_MIN) + return false; + mat[r2][i] = tem2; + } + + return true; } /* Multiply vector VEC1 of length SIZE by a constant CONST1, @@ -4258,7 +4285,7 @@ lambda_vector_equal (lambda_vector vec1, lambda_vector vec2, int size) Ref: Algorithm 2.1 page 33 in "Loop Transformations for Restructuring Compilers" Utpal Banerjee. */ -static void +static bool lambda_matrix_right_hermite (lambda_matrix A, int m, int n, lambda_matrix S, lambda_matrix U) { @@ -4276,24 +4303,26 @@ lambda_matrix_right_hermite (lambda_matrix A, int m, int n, { while (S[i][j] != 0) { - lambda_int sigma, factor, a, b; + lambda_int factor, a, b; a = S[i-1][j]; b = S[i][j]; - sigma = ((a < 0) ^ (b < 0)) ? -1: 1; - unsigned HOST_WIDE_INT abs_a = absu_hwi (a); - unsigned HOST_WIDE_INT abs_b = absu_hwi (b); - factor = sigma * (lambda_int)(abs_a / abs_b); + gcc_assert (a != HOST_WIDE_INT_MIN); + factor = a / b; - lambda_matrix_row_add (S, n, i, i-1, -factor); + if (!lambda_matrix_row_add (S, n, i, i-1, -factor)) + return false; std::swap (S[i], S[i-1]); - lambda_matrix_row_add (U, m, i, i-1, -factor); + if (!lambda_matrix_row_add (U, m, i, i-1, -factor)) + return false; std::swap (U[i], U[i-1]); } } } } + + return true; } /* Determines the overlapping elements due to accesses CHREC_A and @@ -4410,7 +4439,13 @@ analyze_subscript_affine_affine (tree chrec_a, } /* U.A = S */ - lambda_matrix_right_hermite (A, dim, 1, S, U); + if (!lambda_matrix_right_hermite (A, dim, 1, S, U)) + { + *overlaps_a = conflict_fn_not_known (); + *overlaps_b = conflict_fn_not_known (); + *last_conflicts = chrec_dont_know; + goto end_analyze_subs_aa; + } if (S[0][0] < 0) { |