[OpenMP] Implement TR8 `present` motion modifier in runtime (2/2)

[jdenny]

Summary

This patch implements OpenMP runtime support for the OpenMP TR8
present motion modifier for omp target update directives. The
previous patch in this series implements Clang front end support.

[grokos]

(Earlier I posted here an answer for another patch). Looks good, obviously it must be committed after the clang patch.

[jdenny]

Thanks!

openmp/libomptarget/src/omptarget.cpp

for (int32_t i = 0; i < arg_num; ++i) {
 
     void *HstPtrBegin = args[i];
     int64_t MapSize = arg_sizes[i];
     bool IsLast, IsHostPtr;
     void *TgtPtrBegin = Device.getTgtPtrBegin(HstPtrBegin, MapSize, IsLast,
         false, IsHostPtr);
     if (!TgtPtrBegin) {
       DP("hst data:" DPxMOD " not found, becomes a noop\n", DPxPTR(HstPtrBegin));
+      if (arg_types[i] & OMP_TGT_MAPTYPE_PRESENT) {
+        MESSAGE("device mapping required by 'present' motion modifier does not "
+                "exist for host address " DPxMOD " (%ld bytes)",
+                DPxPTR(HstPtrBegin), MapSize);
+        return OFFLOAD_FAIL;
+      }
       continue;
     }
 
     if (RTLs->RequiresFlags & OMP_REQ_UNIFIED_SHARED_MEMORY &&
         TgtPtrBegin == HstPtrBegin) {
       DP("hst data:" DPxMOD " unified and shared, becomes a noop\n",
          DPxPTR(HstPtrBegin));
       continue;

openmp/libomptarget/test/mapping/present/target_update.c

+// --------------------------------------------------
+// Check 'to'
+// --------------------------------------------------
+
+// RUN: %libomptarget-compile-aarch64-unknown-linux-gnu \
+// RUN:   -fopenmp-version=51 -DCLAUSE=to
+// RUN: %libomptarget-run-fail-aarch64-unknown-linux-gnu 2>&1 \
+// RUN: | %fcheck-aarch64-unknown-linux-gnu
+
+// RUN: %libomptarget-compile-powerpc64-ibm-linux-gnu \
+// RUN:   -fopenmp-version=51 -DCLAUSE=to
+// RUN: %libomptarget-run-fail-powerpc64-ibm-linux-gnu 2>&1 \
+// RUN: | %fcheck-powerpc64-ibm-linux-gnu
+
+// RUN: %libomptarget-compile-powerpc64le-ibm-linux-gnu \
+// RUN:   -fopenmp-version=51 -DCLAUSE=to
+// RUN: %libomptarget-run-fail-powerpc64le-ibm-linux-gnu 2>&1 \
+// RUN: | %fcheck-powerpc64le-ibm-linux-gnu
+
+// RUN: %libomptarget-compile-x86_64-pc-linux-gnu \
+// RUN:   -fopenmp-version=51 -DCLAUSE=to
+// RUN: %libomptarget-run-fail-x86_64-pc-linux-gnu 2>&1 \
+// RUN: | %fcheck-x86_64-pc-linux-gnu
+
+// --------------------------------------------------
+// Check 'from'
+// --------------------------------------------------
+
+// RUN: %libomptarget-compile-aarch64-unknown-linux-gnu \
+// RUN:   -fopenmp-version=51 -DCLAUSE=from
+// RUN: %libomptarget-run-fail-aarch64-unknown-linux-gnu 2>&1 \
+// RUN: | %fcheck-aarch64-unknown-linux-gnu
+
+// RUN: %libomptarget-compile-powerpc64-ibm-linux-gnu \
+// RUN:   -fopenmp-version=51 -DCLAUSE=from
+// RUN: %libomptarget-run-fail-powerpc64-ibm-linux-gnu 2>&1 \
+// RUN: | %fcheck-powerpc64-ibm-linux-gnu
+
+// RUN: %libomptarget-compile-powerpc64le-ibm-linux-gnu \
+// RUN:   -fopenmp-version=51 -DCLAUSE=from
+// RUN: %libomptarget-run-fail-powerpc64le-ibm-linux-gnu 2>&1 \
+// RUN: | %fcheck-powerpc64le-ibm-linux-gnu
+
+// RUN: %libomptarget-compile-x86_64-pc-linux-gnu \
+// RUN:   -fopenmp-version=51 -DCLAUSE=from
+// RUN: %libomptarget-run-fail-x86_64-pc-linux-gnu 2>&1 \
+// RUN: | %fcheck-x86_64-pc-linux-gnu
+
+#include <stdio.h>
+
+int main() {
+  int i;
+
+  // CHECK: addr=0x[[#%x,HOST_ADDR:]], size=[[#%u,SIZE:]]
+  fprintf(stderr, "addr=%p, size=%ld\n", &i, sizeof i);
+
+  // CHECK-NOT: Libomptarget
+#pragma omp target enter data map(alloc: i)
+#pragma omp target update CLAUSE(present: i)
+#pragma omp target exit data map(delete: i)
+
+  // CHECK: i is present
+  fprintf(stderr, "i is present\n");
+
+  // CHECK: Libomptarget message: device mapping required by 'present' motion modifier does not exist for host address 0x{{0*}}[[#HOST_ADDR]] ([[#SIZE]] bytes)
+  // CHECK: Libomptarget fatal error 1: failure of target construct while offloading is mandatory
+#pragma omp target update CLAUSE(present: i)
+
+  // CHECK-NOT: i is present
+  fprintf(stderr, "i is present\n");
+
+  return 0;
+}