[llvm] [NFCI][MC][DecoderEmitter] Fix BitWidth for fixed length inst encodings (PR #154934)

[Sergei Barannikov via llvm-commits]

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@@ -0,0 +1,37 @@
+// RUN: not llvm-tblgen -gen-disassembler -I %p/../../../include %s -DTEST1 2>&1 | FileCheck %s -DFILE=%s --check-prefix=CHECK-TEST1
+// RUN: not llvm-tblgen -gen-disassembler -I %p/../../../include %s -DTEST2 2>&1 | FileCheck %s -DFILE=%s --check-prefix=CHECK-TEST2
+
+include "llvm/Target/Target.td"
+
+def archInstrInfo : InstrInfo { }
+
+def arch : Target {
+    let InstructionSet = archInstrInfo;
+}
+
+#ifdef TEST1
+// CHECK-TEST1: [[FILE]]:[[@LINE+1]]:5: error: foo: Size is 16 bits, but Inst bits beyond that are not zero/unset
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s-barannikov wrote:

* No need to check for the file name
* The modern syntax is `#@LINE` (with hash sign).


https://github.com/llvm/llvm-project/pull/154934