From 0275be3a972ecc9dd976232b024cdb366b1619e5 Mon Sep 17 00:00:00 2001 From: Frederic Riss Date: Wed, 12 Nov 2014 23:48:04 +0000 Subject: [PATCH] Allow DWARFFormValue::extractValue to be called with a null CU. Currently FormValues are only used for attributes of DIEs and thus uers always have a CU lying around when calling into the FormValue API. Accelerator tables encode their information using the same Forms as the attributes, thus it is natural to use DWARFFormValue to extract/dump them. There is no CU in that case though. Allow the API to be called with a null CU arguemnt by making the RelocMap lookup conditional on the CU pointer validity. And document this new behvior in the header. (Test coverage for this use of the API comes in the DwarfAccelTable support patch) git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221835 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/llvm/DebugInfo/DWARFFormValue.h | 7 ++++++ lib/DebugInfo/DWARFFormValue.cpp | 32 +++++++++++++------------ 2 files changed, 24 insertions(+), 15 deletions(-) diff --git a/include/llvm/DebugInfo/DWARFFormValue.h b/include/llvm/DebugInfo/DWARFFormValue.h index 162b1deec0f..5bb6d1b9ddb 100644 --- a/include/llvm/DebugInfo/DWARFFormValue.h +++ b/include/llvm/DebugInfo/DWARFFormValue.h @@ -57,6 +57,13 @@ public: bool isFormClass(FormClass FC) const; void dump(raw_ostream &OS, const DWARFUnit *U) const; + + /// \brief extracts a value in data at offset *offset_ptr. + /// + /// The passed DWARFUnit is allowed to be nullptr, in which + /// case no relocation processing will be performed and some + /// kind of forms that depend on Unit information are disallowed. + /// \returns wether the extraction succeeded. bool extractValue(DataExtractor data, uint32_t *offset_ptr, const DWARFUnit *u); bool isInlinedCStr() const { diff --git a/lib/DebugInfo/DWARFFormValue.cpp b/lib/DebugInfo/DWARFFormValue.cpp index 0a478613dae..69b97710a09 100644 --- a/lib/DebugInfo/DWARFFormValue.cpp +++ b/lib/DebugInfo/DWARFFormValue.cpp @@ -139,6 +139,8 @@ bool DWARFFormValue::extractValue(DataExtractor data, uint32_t *offset_ptr, switch (Form) { case DW_FORM_addr: case DW_FORM_ref_addr: { + if (!cu) + return false; uint16_t AddrSize = (Form == DW_FORM_addr) ? cu->getAddressByteSize() @@ -179,8 +181,10 @@ bool DWARFFormValue::extractValue(DataExtractor data, uint32_t *offset_ptr, break; case DW_FORM_data4: case DW_FORM_ref4: { - RelocAddrMap::const_iterator AI = cu->getRelocMap()->find(*offset_ptr); Value.uval = data.getU32(offset_ptr); + if (!cu) + break; + RelocAddrMap::const_iterator AI = cu->getRelocMap()->find(*offset_ptr-4); if (AI != cu->getRelocMap()->end()) Value.uval += AI->second.second; break; @@ -193,13 +197,12 @@ bool DWARFFormValue::extractValue(DataExtractor data, uint32_t *offset_ptr, Value.sval = data.getSLEB128(offset_ptr); break; case DW_FORM_strp: { - RelocAddrMap::const_iterator AI - = cu->getRelocMap()->find(*offset_ptr); - if (AI != cu->getRelocMap()->end()) { - const std::pair &R = AI->second; - Value.uval = data.getU32(offset_ptr) + R.second; - } else - Value.uval = data.getU32(offset_ptr); + Value.uval = data.getU32(offset_ptr); + if (!cu) + break; + RelocAddrMap::const_iterator AI = cu->getRelocMap()->find(*offset_ptr-4); + if (AI != cu->getRelocMap()->end()) + Value.uval += AI->second.second; break; } case DW_FORM_udata: @@ -215,13 +218,12 @@ bool DWARFFormValue::extractValue(DataExtractor data, uint32_t *offset_ptr, break; case DW_FORM_sec_offset: { // FIXME: This is 64-bit for DWARF64. - RelocAddrMap::const_iterator AI - = cu->getRelocMap()->find(*offset_ptr); - if (AI != cu->getRelocMap()->end()) { - const std::pair &R = AI->second; - Value.uval = data.getU32(offset_ptr) + R.second; - } else - Value.uval = data.getU32(offset_ptr); + Value.uval = data.getU32(offset_ptr); + if (!cu) + break; + RelocAddrMap::const_iterator AI = cu->getRelocMap()->find(*offset_ptr-4); + if (AI != cu->getRelocMap()->end()) + Value.uval += AI->second.second; break; } case DW_FORM_flag_present: -- 2.34.1