[llvm] AMDGPU: Defer validation of target assembler directives (PR #207812)

[Matt Arsenault via llvm-commits]

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@@ -9427,6 +9492,16 @@ void AMDGPUAsmParser::onBeginOfFile() {
   if (!getTargetStreamer().getTargetID())
     getTargetStreamer().initializeTargetID(getSTI(),
                                            getSTI().getFeatureString());
+}
+
+void AMDGPUAsmParser::emitTargetDirective() {
+  if (TargetDirectiveEmitted)
+    return;
+  TargetDirectiveEmitted = true;
+
+  if (!getParser().getStreamer().getTargetStreamer() ||
+      getSTI().getTargetTriple().getArch() == Triple::r600)
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arsenm wrote:

Because it's an unrelated target that for historical reasons lives in the same backend. However it doesn't actually support assembly, so it's probably not necessary to bother checking

https://github.com/llvm/llvm-project/pull/207812