[FunctionAttrs] Add additional tests for writeonly (NFC)

Add tests with argmem variations.

Author: nikic

llvm/test/Transforms/FunctionAttrs/writeonly.ll

@@ -317,3 +317,48 @@ define void @fptr_test3(ptr %p, ptr %f) {
   call void %f(ptr nocapture %p) writeonly
   ret void
 }
+
+define void @test_argmem_none_callee(ptr %p) {
+; FNATTRS-LABEL: define {{[^@]+}}@test_argmem_none_callee
+; FNATTRS-SAME: (ptr nocapture [[P:%.*]]) {
+; FNATTRS-NEXT:    call void @direct1_callee(ptr nocapture [[P]]) #[[ATTR9:[0-9]+]]
+; FNATTRS-NEXT:    ret void
+;
+; ATTRIBUTOR-LABEL: define {{[^@]+}}@test_argmem_none_callee
+; ATTRIBUTOR-SAME: (ptr nocapture [[P:%.*]]) {
+; ATTRIBUTOR-NEXT:    call void @direct1_callee(ptr nocapture [[P]]) #[[ATTR8:[0-9]+]]
+; ATTRIBUTOR-NEXT:    ret void
+;
+  call void @direct1_callee(ptr nocapture %p) memory(readwrite, argmem: none)
+  ret void
+}
+
+define void @test_argmem_read_callee(ptr %p) {
+; FNATTRS-LABEL: define {{[^@]+}}@test_argmem_read_callee
+; FNATTRS-SAME: (ptr nocapture [[P:%.*]]) {
+; FNATTRS-NEXT:    call void @direct1_callee(ptr nocapture [[P]]) #[[ATTR10:[0-9]+]]
+; FNATTRS-NEXT:    ret void
+;
+; ATTRIBUTOR-LABEL: define {{[^@]+}}@test_argmem_read_callee
+; ATTRIBUTOR-SAME: (ptr nocapture [[P:%.*]]) {
+; ATTRIBUTOR-NEXT:    call void @direct1_callee(ptr nocapture [[P]]) #[[ATTR9:[0-9]+]]
+; ATTRIBUTOR-NEXT:    ret void
+;
+  call void @direct1_callee(ptr nocapture %p) memory(readwrite, argmem: read)
+  ret void
+}
+
+define void @test_argmem_write_callee(ptr %p) {
+; FNATTRS-LABEL: define {{[^@]+}}@test_argmem_write_callee
+; FNATTRS-SAME: (ptr nocapture [[P:%.*]]) {
+; FNATTRS-NEXT:    call void @direct1_callee(ptr nocapture [[P]]) #[[ATTR11:[0-9]+]]
+; FNATTRS-NEXT:    ret void
+;
+; ATTRIBUTOR-LABEL: define {{[^@]+}}@test_argmem_write_callee
+; ATTRIBUTOR-SAME: (ptr nocapture [[P:%.*]]) {
+; ATTRIBUTOR-NEXT:    call void @direct1_callee(ptr nocapture [[P]]) #[[ATTR10:[0-9]+]]
+; ATTRIBUTOR-NEXT:    ret void
+;
+  call void @direct1_callee(ptr nocapture %p) memory(readwrite, argmem: write)
+  ret void
+}