[gcc/devel/omp/gcc-12] Resolve '-Wsign-compare' issue in 'gcc/omp-low.cc:lower_rec_simd_input_clauses'

[Thomas Schwinge <tschwinge@gcc.gnu.org>]

https://gcc.gnu.org/g:4e32d1582a137d5f34248fdd3e93d35a798f5221

commit 4e32d1582a137d5f34248fdd3e93d35a798f5221
Author: Thomas Schwinge <thomas@codesourcery.com>
Date:   Tue Oct 25 09:45:31 2022 +0200

    Resolve '-Wsign-compare' issue in 'gcc/omp-low.cc:lower_rec_simd_input_clauses'
    
    ..., introduced in og12 commit 55722a87dd223149dcd41ca9c8eba16ad5b3eddc
    "openmp: fix max_vf setting for amdgcn offloading":
    
        In file included from [...]/source-gcc/gcc/coretypes.h:482,
                         from [...]/source-gcc/gcc/omp-low.cc:27:
        [...]/source-gcc/gcc/poly-int.h: In instantiation of ‘typename if_nonpoly<Ca, bool>::type maybe_lt(const Ca&, const poly_int_pod<N, Cb>&) [with unsigned int N = 1; Ca = int; Cb = long unsigned int; typename if_nonpoly<Ca, bool>::type = bool]’:
        [...]/source-gcc/gcc/poly-int.h:1510:7:   required from ‘poly_int<N, typename poly_result<Ca, typename if_nonpoly<Cb>::type>::type> ordered_max(const poly_int_pod<N, C>&, const Cb&) [with unsigned int N = 1; Ca = long unsigned int; Cb = int; typename poly_result<Ca, typename if_nonpoly<Cb>::type>::type = long unsigned int; typename if_nonpoly<Cb>::type = int]’
        [...]/source-gcc/gcc/omp-low.cc:5180:33:   required from here
        [...]/source-gcc/gcc/poly-int.h:1384:12: error: comparison of integer expressions of different signedness: ‘const int’ and ‘const long unsigned int’ [-Werror=sign-compare]
         1384 |   return a < b.coeffs[0];
              |          ~~^~~~~~~~~~~
        [...]/source-gcc/gcc/poly-int.h: In instantiation of ‘typename if_nonpoly<Cb, bool>::type maybe_lt(const poly_int_pod<N, C>&, const Cb&) [with unsigned int N = 1; Ca = long unsigned int; Cb = int; typename if_nonpoly<Cb, bool>::type = bool]’:
        [...]/source-gcc/gcc/poly-int.h:1515:2:   required from ‘poly_int<N, typename poly_result<Ca, typename if_nonpoly<Cb>::type>::type> ordered_max(const poly_int_pod<N, C>&, const Cb&) [with unsigned int N = 1; Ca = long unsigned int; Cb = int; typename poly_result<Ca, typename if_nonpoly<Cb>::type>::type = long unsigned int; typename if_nonpoly<Cb>::type = int]’
        [...]/source-gcc/gcc/omp-low.cc:5180:33:   required from here
        [...]/source-gcc/gcc/poly-int.h:1373:22: error: comparison of integer expressions of different signedness: ‘const long unsigned int’ and ‘const int’ [-Werror=sign-compare]
         1373 |   return a.coeffs[0] < b;
              |          ~~~~~~~~~~~~^~~
    
            gcc/
            * omp-low.cc (lower_rec_simd_input_clauses): For 'ordered_max',
            cast 'omp_max_simt_vf ()', 'omp_max_simd_vf ()' to 'unsigned'.

Diff:
---
 gcc/omp-low.cc | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/gcc/omp-low.cc b/gcc/omp-low.cc
index b5b2681b654..002f91d930a 100644
--- a/gcc/omp-low.cc
+++ b/gcc/omp-low.cc
@@ -5177,8 +5177,8 @@ lower_rec_simd_input_clauses (tree new_var, omp_context *ctx,
       if (omp_maybe_offloaded_ctx (ctx))
 	{
 	  if (sctx->is_simt)
-	    sctx->max_vf = ordered_max (sctx->max_vf, omp_max_simt_vf ());
-	  sctx->max_vf = ordered_max (sctx->max_vf, omp_max_simd_vf ());
+	    sctx->max_vf = ordered_max (sctx->max_vf, (unsigned) omp_max_simt_vf ());
+	  sctx->max_vf = ordered_max (sctx->max_vf, (unsigned) omp_max_simd_vf ());
 	}
       if (maybe_gt (sctx->max_vf, 1U))
 	{