This properly uses lambda_int instead of truncating the direction vector to int which leads to false unexpected negative values.
Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed. 2021-11-23 Richard Biener <rguent...@suse.de> PR tree-optimization/103361 * gimple-loop-jam.c (adjust_unroll_factor): Use lambda_int for the dependence distance. * tree-data-ref.c (print_lambda_vector): Properly print a lambda_int. * g++.dg/torture/pr103361.C: New testcase. --- gcc/gimple-loop-jam.c | 4 ++-- gcc/testsuite/g++.dg/torture/pr103361.C | 18 ++++++++++++++++++ gcc/tree-data-ref.c | 2 +- 3 files changed, 21 insertions(+), 3 deletions(-) create mode 100644 gcc/testsuite/g++.dg/torture/pr103361.C diff --git a/gcc/gimple-loop-jam.c b/gcc/gimple-loop-jam.c index 666f740f86d..933a4e0e6b0 100644 --- a/gcc/gimple-loop-jam.c +++ b/gcc/gimple-loop-jam.c @@ -402,10 +402,10 @@ adjust_unroll_factor (class loop *inner, struct data_dependence_relation *ddr, a >= N, or b > 0, or b is zero and a > 0. Otherwise the unroll factor needs to be limited so that the first condition holds. That may limit the factor down to zero in the worst case. */ - int dist = dist_v[0]; + lambda_int dist = dist_v[0]; if (dist < 0) gcc_unreachable (); - else if ((unsigned)dist >= *unroll) + else if (dist >= (lambda_int)*unroll) ; else if (lambda_vector_zerop (dist_v + 1, DDR_NB_LOOPS (ddr) - 1)) { diff --git a/gcc/testsuite/g++.dg/torture/pr103361.C b/gcc/testsuite/g++.dg/torture/pr103361.C new file mode 100644 index 00000000000..ec1d6e1bae4 --- /dev/null +++ b/gcc/testsuite/g++.dg/torture/pr103361.C @@ -0,0 +1,18 @@ +/* { dg-do compile } */ +/* { dg-additional-options "-floop-unroll-and-jam" } */ + +char a, b; +extern unsigned short c[]; +extern bool d[]; +const unsigned short &e(const unsigned short &f, const unsigned short &g) { + if (g < f) + return g; + return f; +} +void k() { + for (int h = 0; b; h += 3) + for (unsigned long i = 0; i < 11104842004558084287ULL; + i += -11104842004558084300ULL) + for (bool j(e(6, e(6, c[h + i]))); j < (bool)a; j = 7) + d[7] = 0; +} diff --git a/gcc/tree-data-ref.c b/gcc/tree-data-ref.c index 46f4ffedb48..9b6ca1a91e5 100644 --- a/gcc/tree-data-ref.c +++ b/gcc/tree-data-ref.c @@ -388,7 +388,7 @@ print_lambda_vector (FILE * outfile, lambda_vector vector, int n) int i; for (i = 0; i < n; i++) - fprintf (outfile, "%3d ", (int)vector[i]); + fprintf (outfile, HOST_WIDE_INT_PRINT_DEC " ", vector[i]); fprintf (outfile, "\n"); } -- 2.31.1