diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp index 72065a1610f351..3049e7caf351f7 100644 --- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp +++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp @@ -1531,27 +1531,30 @@ static bool validThroughout(LexicalScopes &LScopes, if (LSRange.size() == 0) return false; - - // Determine if the DBG_VALUE is valid at the beginning of its lexical block. const MachineInstr *LScopeBegin = LSRange.front().first; - // Early exit if the lexical scope begins outside of the current block. - if (LScopeBegin->getParent() != MBB) - return false; - - MachineBasicBlock::const_reverse_iterator Pred(DbgValue); - for (++Pred; Pred != MBB->rend(); ++Pred) { - if (Pred->getFlag(MachineInstr::FrameSetup)) - break; - auto PredDL = Pred->getDebugLoc(); - if (!PredDL || Pred->isMetaInstruction()) - continue; - // Check whether the instruction preceding the DBG_VALUE is in the same - // (sub)scope as the DBG_VALUE. - if (DL->getScope() == PredDL->getScope()) - return false; - auto *PredScope = LScopes.findLexicalScope(PredDL); - if (!PredScope || LScope->dominates(PredScope)) + // If the scope starts before the DBG_VALUE then we may have a negative + // result. Otherwise the location is live coming into the scope and we + // can skip the following checks. + if (!Ordering.isBefore(DbgValue, LScopeBegin)) { + // Exit if the lexical scope begins outside of the current block. + if (LScopeBegin->getParent() != MBB) return false; + + MachineBasicBlock::const_reverse_iterator Pred(DbgValue); + for (++Pred; Pred != MBB->rend(); ++Pred) { + if (Pred->getFlag(MachineInstr::FrameSetup)) + break; + auto PredDL = Pred->getDebugLoc(); + if (!PredDL || Pred->isMetaInstruction()) + continue; + // Check whether the instruction preceding the DBG_VALUE is in the same + // (sub)scope as the DBG_VALUE. + if (DL->getScope() == PredDL->getScope()) + return false; + auto *PredScope = LScopes.findLexicalScope(PredDL); + if (!PredScope || LScope->dominates(PredScope)) + return false; + } } // If the range of the DBG_VALUE is open-ended, report success. diff --git a/llvm/test/DebugInfo/X86/inlined-formal-parameter.ll b/llvm/test/DebugInfo/X86/inlined-formal-parameter.ll index 00562df3922b45..376505f9832e9e 100644 --- a/llvm/test/DebugInfo/X86/inlined-formal-parameter.ll +++ b/llvm/test/DebugInfo/X86/inlined-formal-parameter.ll @@ -19,8 +19,7 @@ ; CHECK: DW_TAG_inlined_subroutine ; CHECK-NEXT: DW_AT_abstract_origin {{.*}} "bar" ; CHECK: DW_TAG_formal_parameter -; CHECK-NEXT: DW_AT_location [DW_FORM_data4] ( -; CHECK-NEXT: [{{.*}}, {{.*}}): DW_OP_consts +0) +; CHECK-NEXT: DW_AT_const_value [DW_FORM_sdata] (0) ; CHECK-NEXT: DW_AT_abstract_origin {{.*}} "a" target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"