llvm-6502/test/Assembler/metadata-null-operands.ll

; RUN: llvm-as < %s | llvm-dis | llvm-as | llvm-dis | FileCheck %s
; RUN: verify-uselistorder %s

; Don't crash on null operands.  (If/when we add a verify check for these, we
; should disable the verifier for this test and remove this comment; the test
; is still important.)
!named = !{!0, !1}
!0 = !MDDerivedType(tag: DW_TAG_pointer_type, baseType: null)
!1 = !MDCompileUnit(language: DW_LANG_C, file: null)

; CHECK: !named = !{!0, !1}
; CHECK: !0 = !MDDerivedType({{.*}}baseType: null{{.*}})
; CHECK: !1 = !MDCompileUnit({{.*}}file: null{{.*}})
Bitcode: Stop assuming non-null fields When writing the bitcode serialization for the new debug info hierarchy, I assumed two fields would never be null. Drop that assumption, since it's brittle (and crashes the `BitcodeWriter` if wrong), and is a check better left for the verifier anyway. (No need for a bitcode upgrade here, since the new hierarchy is still not in place.) The fields in question are `MDCompileUnit::getFile()` and `MDDerivedType::getBaseType()`, the latter of which isn't null in test/Transforms/Mem2Reg/ConvertDebugInfo2.ll (see !14, a pointer to nothing). While the testcase might have bitrotted, there's no reason for the bitcode format to rely on non-null for metadata operands. This also fixes a bug in `AsmWriter` where if the `file:` is null it isn't emitted (caught by the double-round trip in the testcase I'm adding) -- this is a required field in `LLParser`. I'll circle back to ConvertDebugInfo2. Once the specialized nodes are in place, I'll be trying to turn the debug info verifier back on by default (in the newer module pass form committed r206300) and throwing more logic in there. If the testcase has bitrotted (as opposed to me not understanding the schema correctly) I'll fix it then. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229960 91177308-0d34-0410-b5e6-96231b3b80d8 2015-02-20 03:17:58 +00:00			`; RUN: llvm-as < %s \| llvm-dis \| llvm-as \| llvm-dis \| FileCheck %s`
			`; RUN: verify-uselistorder %s`

			`; Don't crash on null operands. (If/when we add a verify check for these, we`
			`; should disable the verifier for this test and remove this comment; the test`
			`; is still important.)`
			`!named = !{!0, !1}`
			`!0 = !MDDerivedType(tag: DW_TAG_pointer_type, baseType: null)`
			`!1 = !MDCompileUnit(language: DW_LANG_C, file: null)`

			`; CHECK: !named = !{!0, !1}`
			`; CHECK: !0 = !MDDerivedType({{.}}baseType: null{{.}})`
			`; CHECK: !1 = !MDCompileUnit({{.}}file: null{{.}})`