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1// Check that omp atomic compare handles signedness of integer comparisons2// correctly.3//4// At one time, a bug sometimes reversed the signedness.5 6// RUN: %libomptarget-compile-generic7// RUN: %libomptarget-run-generic | %fcheck-generic8// RUN: %libomptarget-compileopt-generic -fopenmp-version=519// RUN: %libomptarget-run-generic | %fcheck-generic10 11// High parallelism increases our chances of detecting a lack of atomicity.12#define NUM_THREADS_TRY 25613 14#include <limits.h>15#include <omp.h>16#include <stdio.h>17 18int main() {19 // CHECK: signed: num_threads=[[#NUM_THREADS:]]{{$}}20 // CHECK-NEXT: signed: xs=[[#NUM_THREADS-1]]{{$}}21 int xs = -1;22 int numThreads;23#pragma omp target parallel for num_threads(NUM_THREADS_TRY) \24 map(tofrom : xs, numThreads)25 for (int i = 0; i < omp_get_num_threads(); ++i) {26#pragma omp atomic compare27 if (xs < i) {28 xs = i;29 }30 if (i == 0)31 numThreads = omp_get_num_threads();32 }33 printf("signed: num_threads=%d\n", numThreads);34 printf("signed: xs=%d\n", xs);35 36 // CHECK-NEXT: unsigned: xu=0x0{{$}}37 unsigned xu = UINT_MAX;38#pragma omp target parallel for num_threads(NUM_THREADS_TRY) map(tofrom : xu)39 for (int i = 0; i < omp_get_num_threads(); ++i) {40#pragma omp atomic compare41 if (xu > i) {42 xu = i;43 }44 }45 printf("unsigned: xu=0x%x\n", xu);46 return 0;47}48