From 7814ec18b095d40af95f362ff668a68915982e45 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Magnus=20L=C3=A5ng?= Date: Wed, 11 May 2016 13:39:53 +0200 Subject: hipe_llvm: Allow LLVM-generated constants Since 3.7, LLVM sometimes generates SSE constants in a special constant section with the requisite alignment (".rodata.cst16"). This broke hipe_llvm since it assumed that all constants that were linked from the text section were constants generated by hipe_llvm. As this is the first time alignments larger than 8 have been required, some small changes were required to hipe_consttab and hipe_bifs:alloc_data/2. Note that hipe_bifs:alloc_data/2 still assumes that erl_alloc will provide the requisite alignment. --- erts/emulator/hipe/hipe_bif0.c | 10 +++++++--- lib/hipe/llvm/elf_format.erl | 7 +++++++ lib/hipe/llvm/hipe_llvm_main.erl | 31 ++++++++++++++++++++++++++++--- lib/hipe/misc/hipe_consttab.erl | 13 ++++++++++++- lib/hipe/misc/hipe_consttab.hrl | 2 +- 5 files changed, 55 insertions(+), 8 deletions(-) diff --git a/erts/emulator/hipe/hipe_bif0.c b/erts/emulator/hipe/hipe_bif0.c index 48cfafb8c5..3f95fb67eb 100644 --- a/erts/emulator/hipe/hipe_bif0.c +++ b/erts/emulator/hipe/hipe_bif0.c @@ -418,6 +418,8 @@ BIF_RETTYPE hipe_bifs_enter_code_2(BIF_ALIST_2) BIF_RET(make_tuple(hp)); } +#define IS_POWER_OF_TWO(Val) (((Val) > 0) && (((Val) & ((Val)-1)) == 0)) + /* * Allocate memory for arbitrary non-Erlang data. */ @@ -427,16 +429,18 @@ BIF_RETTYPE hipe_bifs_alloc_data_2(BIF_ALIST_2) void *block; if (is_not_small(BIF_ARG_1) || is_not_small(BIF_ARG_2) || - (align = unsigned_val(BIF_ARG_1), - align != sizeof(long) && align != sizeof(double))) + (align = unsigned_val(BIF_ARG_1), !IS_POWER_OF_TWO(align))) BIF_ERROR(BIF_P, BADARG); nrbytes = unsigned_val(BIF_ARG_2); if (nrbytes == 0) BIF_RET(make_small(0)); block = erts_alloc(ERTS_ALC_T_HIPE, nrbytes); - if ((unsigned long)block & (align-1)) + if ((unsigned long)block & (align-1)) { fprintf(stderr, "%s: erts_alloc(%lu) returned %p which is not %lu-byte aligned\r\n", __FUNCTION__, (unsigned long)nrbytes, block, (unsigned long)align); + erts_free(ERTS_ALC_T_HIPE, block); + BIF_ERROR(BIF_P, EXC_NOTSUP); + } BIF_RET(address_to_term(block, BIF_P)); } diff --git a/lib/hipe/llvm/elf_format.erl b/lib/hipe/llvm/elf_format.erl index 4155dff7c4..b3c5ecddab 100644 --- a/lib/hipe/llvm/elf_format.erl +++ b/lib/hipe/llvm/elf_format.erl @@ -23,6 +23,8 @@ get_exn_handlers/1, %% Symbols elf_symbols/1, + %% Sections + section_contents/2, %% Main interface read/1 ]). @@ -312,6 +314,11 @@ elf_section(?SHN_ABS, #elf{}) -> abs; elf_section(Index, #elf{sec_idx=SecIdx}) when Index =< tuple_size(SecIdx) -> element(Index, SecIdx). +%% Reads the contents of a section from an object +-spec section_contents(elf_shdr(), elf()) -> binary(). +section_contents(#elf_shdr{offset=Offset, size=Size}, #elf{file=ElfBin}) -> + get_binary_segment(ElfBin, Offset, Size). + %%------------------------------------------------------------------------------ %% Functions to manipulate Symbol Table %%------------------------------------------------------------------------------ diff --git a/lib/hipe/llvm/hipe_llvm_main.erl b/lib/hipe/llvm/hipe_llvm_main.erl index 3ab213f94c..476d6fb49c 100644 --- a/lib/hipe/llvm/hipe_llvm_main.erl +++ b/lib/hipe/llvm/hipe_llvm_main.erl @@ -13,7 +13,7 @@ %% chain is invoked in order to produce an object file. rtl_to_native(MFA, RTL, Roots, Options) -> %% Compile to LLVM and get Instruction List (along with infos) - {LLVMCode, RelocsDict, ConstTab} = + {LLVMCode, RelocsDict0, ConstTab0} = hipe_rtl_to_llvm:translate(RTL, Roots), %% Fix function name to an acceptable LLVM identifier (needed for closures) {_Module, Fun, Arity} = hipe_rtl_to_llvm:fix_mfa_name(MFA), @@ -32,10 +32,11 @@ rtl_to_native(MFA, RTL, Roots, Options) -> {SwitchInfos, ExposedClosures} = correlate_labels(Tables, Labels), %% SwitchInfos: [{"table_50", [Labels]}] %% ExposedClosures: [{"table_closures", [Labels]}] - + %% Labelmap contains the offsets of the labels in the code that are %% used for switch's jump tables - LabelMap = create_labelmap(MFA, SwitchInfos, RelocsDict), + LabelMap = create_labelmap(MFA, SwitchInfos, RelocsDict0), + {RelocsDict, ConstTab} = extract_constants(RelocsDict0, ConstTab0, Obj), %% Get relocation info TextRelocs = elf_format:extract_rela(Obj, ?TEXT), %% AccRefs contains the offsets of all references to relocatable symbols in @@ -219,6 +220,25 @@ insert_to_labelmap([{Key, Value}|Rest], LabelMap) -> insert_to_labelmap(Rest, LabelMap) end. +%% Find any LLVM-generated constants and add them to the constant table +extract_constants(RelocsDict0, ConstTab0, Obj) -> + TextRelocs = elf_format:extract_rela(Obj, ?TEXT), + AnonConstSections = + lists:usort([{Sec, Offset} + || #elf_rel{symbol=#elf_sym{type=section, section=Sec}, + addend=Offset} <- TextRelocs]), + lists:foldl( + fun({#elf_shdr{name=Name, type=progbits, addralign=Align, entsize=EntSize, + size=Size} = Section, Offset}, {RelocsDict1, ConstTab1}) + when EntSize > 0, 0 =:= Size rem EntSize, 0 =:= Offset rem EntSize -> + SectionBin = elf_format:section_contents(Section, Obj), + Constant = binary:part(SectionBin, Offset, EntSize), + {ConstTab, ConstLbl} = + hipe_consttab:insert_binary_const(ConstTab1, Align, Constant), + {dict:store({anon, Name, Offset}, {constant, ConstLbl}, RelocsDict1), + ConstTab} + end, {RelocsDict0, ConstTab0}, AnonConstSections). + %% @doc Correlate object file relocation symbols with info from translation to %% llvm code. fix_relocations(Relocs, RelocsDict, MFA) -> @@ -269,6 +289,11 @@ fix_reloc(#elf_rel{symbol=#elf_sym{name=Name, section=#elf_shdr{name=?RODATA}, case dict:fetch(Name, RelocsDict) of {switch, _, JTabLab} -> %% Treat switch exactly as constant {?LOAD_ADDRESS, Offset, {constant, JTabLab}} + end; +fix_reloc(#elf_rel{symbol=#elf_sym{type=section, section=#elf_shdr{name=Name}}, + offset=Offset, type=?ABS_T, addend=Addend}, RelocsDict, _) -> + case dict:fetch({anon, Name, Addend}, RelocsDict) of + {constant, Label} -> {?LOAD_ADDRESS, Offset, {constant, Label}} end. %%------------------------------------------------------------------------------ diff --git a/lib/hipe/misc/hipe_consttab.erl b/lib/hipe/misc/hipe_consttab.erl index f361edc79c..226b20fa46 100644 --- a/lib/hipe/misc/hipe_consttab.erl +++ b/lib/hipe/misc/hipe_consttab.erl @@ -87,7 +87,8 @@ % {NewTab, Lbl} insert_sorted_block/4, insert_block/3, - %% insert_global_word/2, + insert_binary_const/3, + %% insert_global_word/2, %% insert_global_block/4, %% update_word/3, % update_word(ConstTab, Value) -> {NewTab, Lbl} %% update_block/5, @@ -196,6 +197,16 @@ insert_block({ConstTab, RefToLabels, NextLabel}, ElementType, InitList) -> {ElementType,InitList}), {insert_backrefs(NewTa, Id, ReferredLabels), Id}. +%% @doc Inserts a binary constant literal into the const table. +-spec insert_binary_const(hipe_consttab(), ct_alignment(), binary()) -> + {hipe_consttab(), hipe_constlbl()}. +insert_binary_const(ConstTab, Alignment, Binary) + when (Alignment =:= 4 orelse Alignment =:= 8 orelse Alignment =:= 16 + orelse Alignment =:= 32), is_binary(Binary), + size(Binary) rem Alignment =:= 0 -> + insert_const(ConstTab, block, Alignment, false, + {byte, binary_to_list(Binary)}). + %% @spec (ConstTab::hipe_consttab(), ElementType::element_type(), %% InitList::block(), SortOrder) -> {hipe_consttab(), hipe_constlbl()} diff --git a/lib/hipe/misc/hipe_consttab.hrl b/lib/hipe/misc/hipe_consttab.hrl index d2dbbe509c..550da0455c 100644 --- a/lib/hipe/misc/hipe_consttab.hrl +++ b/lib/hipe/misc/hipe_consttab.hrl @@ -20,7 +20,7 @@ %% %%----------------------------------------------------------------------------- --type ct_alignment() :: 4 | 8. +-type ct_alignment() :: 4 | 8 | 16 | 32. -type hipe_constlbl() :: non_neg_integer(). -type hipe_consttab() :: {dict:dict(), [hipe_constlbl()], hipe_constlbl()}. -- cgit v1.2.3