[mlir][llvm] Consolidate function attribute import tests (NFC).

[gysit]

Summary

The revision puts the function attributes tests previously distributed
accross multiple files int a single function-attributes.ll test file.

mlir/test/Target/LLVMIR/Import/basic.ll

 ; RUN: mlir-translate -import-llvm %s | FileCheck %s
 ; RUN: mlir-translate -import-llvm -mlir-print-debuginfo %s | FileCheck %s --check-prefix=CHECK-DBG
 
 ; CHECK-DBG: #[[UNKNOWNLOC:.+]] = loc(unknown)
 
 @global = external global double, align 8
 
-;
-; Linkage on functions.
-;
-
-; CHECK: llvm.func internal @func_internal
-define internal void @func_internal() {
-  ret void
-}
-
 ; CHECK: llvm.func @fe(i32) -> f32
 declare float @fe(i32)
 
-; CHECK: llvm.func internal spir_funccc @spir_func_internal()
-define internal spir_func void @spir_func_internal() {
-  ret void
-}
-
 ; FIXME: function attributes.
 ; CHECK-LABEL: llvm.func internal @f1(%arg0: i64) -> i32 attributes {dso_local} {
 ; CHECK-DBG: llvm.func internal @f1(%arg0: i64 loc(unknown)) -> i32 attributes {dso_local} {
 ; CHECK: %[[c2:[0-9]+]] = llvm.mlir.constant(2 : i32) : i32
 ; CHECK: %[[c1:[0-9]+]] = llvm.mlir.constant(true) : i1
 ; CHECK: %[[c43:[0-9]+]] = llvm.mlir.constant(43 : i32) : i32
 ; CHECK: %[[c42:[0-9]+]] = llvm.mlir.constant(42 : i32) : i32
 define internal dso_local i32 @f1(i64 %a) norecurse {

mlir/test/Target/LLVMIR/Import/func-attrs.ll

-; RUN: mlir-translate -import-llvm %s | FileCheck %s
-
-; CHECK: llvm.func @foo(%arg0: !llvm.ptr {llvm.byval = i64}, %arg1: !llvm.ptr {llvm.byref = i64}, %arg2: !llvm.ptr {llvm.sret = i64}, %arg3: !llvm.ptr {llvm.inalloca = i64})
-define void @foo(ptr byval(i64) %arg0, ptr byref(i64) %arg1, ptr sret(i64) %arg2, ptr inalloca(i64) %arg3) {
-  ret void
-}

mlir/test/Target/LLVMIR/Import/function-attributes.ll

+; RUN: mlir-translate -import-llvm -split-input-file %s | FileCheck %s
+
+; CHECK: llvm.func internal @func_internal
+define internal void @func_internal() {
+  ret void
+}
+
+; CHECK: llvm.func internal spir_funccc @spir_func_internal()
+define internal spir_func void @spir_func_internal() {
+  ret void
+}
+
+; // -----
+
+; CHECK-LABEL: @func_readnone
+; CHECK-SAME:  attributes {llvm.readnone}
+; CHECK:   llvm.return
+define void @func_readnone() readnone {
+  ret void
+}
+
+; CHECK-LABEL: @func_readnone_indirect
+; CHECK-SAME:  attributes {llvm.readnone}
+declare void @func_readnone_indirect() #0
+attributes #0 = { readnone }
+
+; // -----
+
+; CHECK-LABEL: @func_arg_attrs
+; CHECK-SAME:  !llvm.ptr {llvm.byval = i64}
+; CHECK-SAME:  !llvm.ptr {llvm.byref = i64}
+; CHECK-SAME:  !llvm.ptr {llvm.sret = i64}
+; CHECK-SAME:  !llvm.ptr {llvm.inalloca = i64}
+define void @func_arg_attrs(
+    ptr byval(i64) %arg0,
+    ptr byref(i64) %arg1,
+    ptr sret(i64) %arg2,
+    ptr inalloca(i64) %arg3) {
+  ret void
+}

mlir/test/Target/LLVMIR/Import/function_attributes.ll

-; RUN: mlir-translate -import-llvm -split-input-file %s | FileCheck %s
-
-// -----
-
-; CHECK: llvm.func @readnone_attr() attributes {llvm.readnone}
-declare void @readnone_attr() #0
-attributes #0 = { readnone }
-
-// -----
-
-; CHECK: llvm.func @readnone_attr() attributes {llvm.readnone} {
-; CHECK:   llvm.return
-; CHECK: }
-define void @readnone_attr() readnone {
-entry:
-  ret void
-}