[Xcore] Set Int_MemBarrier as a meta-instruction

[nigelp-xmos]

As the test is specifying targets, I think it needs to be in both X86 and XCore areas. Otherwise compilers not supporting those targets will attempt the test.

There is "REQUIRES: ...-registered-target" (for example in attr-btf_tag.ll) but I think "REQUIRES: x86-registered-target,xcore-registered-target" would only test compilers supporting both targets, which is not right.

I suppose an alternative to duplicating is a new REQUIRES name but perhaps that's excessive for one test, and duplicating is simplest?

[skan]

In D121982#3392172, @nigelp-xmos wrote:

As the test is specifying targets, I think it needs to be in both X86 and XCore areas. Otherwise compilers not supporting those targets will attempt the test.

There is "REQUIRES: ...-registered-target" (for example in attr-btf_tag.ll) but I think "REQUIRES: x86-registered-target,xcore-registered-target" would only test compilers supporting both targets, which is not right.

I suppose an alternative to duplicating is a new REQUIRES name but perhaps that's excessive for one test, and duplicating is simplest?

Thanks! Good catch! I will do that.

[skan]

Duplicate the test

[nigelp-xmos]

LGTM thanks

llvm/lib/Target/XCore/XCoreInstrInfo.td

 let usesCustomInserter = 1 in {
   def SELECT_CC : PseudoInstXCore<(outs GRRegs:$dst),
                               (ins GRRegs:$cond, GRRegs:$T, GRRegs:$F),
                               "# SELECT_CC PSEUDO!",
                               [(set GRRegs:$dst,
                                  (select GRRegs:$cond, GRRegs:$T, GRRegs:$F))]>;
 }
 
-let hasSideEffects = 1 in
+let hasSideEffects = 1, isMeta = 1 in
 def Int_MemBarrier : PseudoInstXCore<(outs), (ins), "#MEMBARRIER",
                                      [(XCoreMemBarrier)]>;
 
 //===----------------------------------------------------------------------===//
 // Instructions
 //===----------------------------------------------------------------------===//
 
 // Three operand short

llvm/test/DebugInfo/XCore/dwarf-mem-barrier.ll

+; Check .loc directive is emitted at correct position
+; RUN: llc -O0 -mtriple xcore-linux-gnu <%s | FileCheck %s
+
+; CHECK:  #MEMBARRIER
+; CHECK:  #MEMBARRIER
+; CHECK:  ldc r0, 0
+; CHECK:  stw r0, sp[0]
+; CHECK:  .loc  1 1 14 prologue_end             # none.c:1:14
+
+define dso_local i32 @main() !dbg !7 {
+entry:
+  fence acquire, !dbg !9
+  fence release, !dbg !9
+  %retval = alloca i32, align 4
+  store i32 0, i32* %retval, align 4
+  ret i32 0, !dbg !9
+}
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3, !4, !5}
+!llvm.ident = !{!6}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang", isOptimized: false, runtimeVersion: 0, emissionKind: DebugDirectivesOnly, enums: !2, splitDebugInlining: false, nameTableKind: None)
+!1 = !DIFile(filename: "none.c", directory: "/temp")
+!2 = !{}
+!3 = !{i32 2, !"Tracing", i32 1}
+!4 = !{i32 2, !"Debug Info Version", i32 3}
+!5 = !{i32 1, !"wchar_size", i32 4}
+!6 = !{!"clang version 11.0.0"}
+!7 = distinct !DISubprogram(name: "main", scope: !1, file: !1, line: 1, type: !8, scopeLine: 1, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !2)
+!8 = !DISubroutineType(types: !2)
+!9 = !DILocation(line: 1, column: 14, scope: !7)

llvm/test/DebugInfo/XCore/lit.local.cfg

+if not 'XCore' in config.root.targets:
+    config.unsupported = True