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0187151352
For reasons which are unclear, but possibly due to lack of any known use cases
when the code was written, LUL on i686/x86_64-linux only accepts CFA (canonical
frame address) expressions of the form SP+offset or FP+offset. However, on
Fedora 25 x86_64 and Ubuntu 16.10 x86_64, at least one address range per object
uses a Dwarf expression for the CFA, for example:
00000018 000000000024 0000001c FDE cie=00000000 pc=0000000031e0..0000000031f0
DW_CFA_def_cfa_offset: 16
DW_CFA_advance_loc: 6 to 00000000000031e6
DW_CFA_def_cfa_offset: 24
DW_CFA_advance_loc: 10 to 00000000000031f0
DW_CFA_def_cfa_expression(
DW_OP_breg7 (rsp): 8; DW_OP_breg16 (rip): 0; DW_OP_lit15; DW_OP_and;
DW_OP_lit11; DW_OP_ge; DW_OP_lit3; DW_OP_shl; DW_OP_plus)
producing the following complaint from LUL:
can't summarise: SVMA=0x31f0: rule for DW_REG_CFA: invalid |how|, expr=LExpr(PFXEXPR,0,0)
Given that LUL is capable of handling such a CFA expression, it seems artificial
to stop it doing so. This patch changes Summariser::Rule() so as to allow such
expressions.
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|---|---|---|
| .. | ||
| AutoObjectMapper.cpp | ||
| AutoObjectMapper.h | ||
| LulCommon.cpp | ||
| LulCommonExt.h | ||
| LulDwarf.cpp | ||
| LulDwarfExt.h | ||
| LulDwarfInt.h | ||
| LulDwarfSummariser.cpp | ||
| LulDwarfSummariser.h | ||
| LulElf.cpp | ||
| LulElfExt.h | ||
| LulElfInt.h | ||
| LulMain.cpp | ||
| LulMain.h | ||
| LulMainInt.h | ||
| platform-linux-lul.cpp | ||
| platform-linux-lul.h | ||