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* [mips][mips64r6] Add Relocations R_MIPS_PCHI16, R_MIPS_PCLO16 Zoran Jovanovic2014-05-27
| | | | | | | Differential Revision: http://reviews.llvm.org/D3860 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209659 91177308-0d34-0410-b5e6-96231b3b80d8
* Fix pr19645.Rafael Espindola2014-05-03
| | | | | | | | | | | | | | | | The fix itself is fairly simple: move getAccessVariant to MCValue so that we replace the old weak expression evaluation with the far more general EvaluateAsRelocatable. This then requires that EvaluateAsRelocatable stop when it finds a non trivial reference kind. And that in turn requires the ELF writer to look harder for weak references. Last but not least, this found a case where we were being bug by bug compatible with gas and accepting an invalid input. I reported pr19647 to track it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207920 91177308-0d34-0410-b5e6-96231b3b80d8
* Parse and create GOT_PREL relocations.Joerg Sonnenberger2014-04-29
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207526 91177308-0d34-0410-b5e6-96231b3b80d8
* Add an option for evaluating past symbols.Rafael Espindola2014-04-28
| | | | | | | | | | | | | When evaluating an assembly expression for a relocation, we want to stop at MCSymbols that are in the symbol table, even if they are variables. This is needed since the semantics may require that the relocation use them. That is not the case when computing the value of a symbol in the symbol table. There are no relocations in this case and we have to keep going until we hit a section or find out that the expression doesn't have an assembly time value. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207445 91177308-0d34-0410-b5e6-96231b3b80d8
* Spread some const around for non-mutating uses of MCSymbolData.David Blaikie2014-04-24
| | | | | | | | I discovered this const-hole while attempting to coalesnce the Symbol and SymbolMap data structures. There's some pending issues with that, but I figured this change was easy to flush early. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207124 91177308-0d34-0410-b5e6-96231b3b80d8
* [Modules] Fix potential ODR violations by sinking the DEBUG_TYPEChandler Carruth2014-04-22
| | | | | | | definition below all the header #include lines. This updates most of the miscellaneous other lib/... directories. A few left though. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206845 91177308-0d34-0410-b5e6-96231b3b80d8
* [C++11] More 'nullptr' conversion or in some cases just using a boolean ↵Craig Topper2014-04-13
| | | | | | check instead of comparing to nullptr. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206129 91177308-0d34-0410-b5e6-96231b3b80d8
* ARM64: initial backend importTim Northover2014-03-29
| | | | | | | | | | | | This adds a second implementation of the AArch64 architecture to LLVM, accessible in parallel via the "arm64" triple. The plan over the coming weeks & months is to merge the two into a single backend, during which time thorough code review should naturally occur. Everything will be easier with the target in-tree though, hence this commit. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205090 91177308-0d34-0410-b5e6-96231b3b80d8
* Look through variables when computing relocations.Rafael Espindola2014-03-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Given bar = foo + 4 .long bar MC would eat the 4. GNU as includes it in the relocation. The rule seems to be that a variable that defines a symbol is used in the relocation and one that does not define a symbol is evaluated and the result included in the relocation. Fixing this unfortunately required some other changes: * Since the variable is now evaluated, it would prevent the ELF writer from noticing the weakref marker the elf streamer uses. This patch then replaces that with a VariantKind in MCSymbolRefExpr. * Using VariantKind then requires us to look past other VariantKind to see .weakref bar,foo call bar@PLT doing this also fixes zed = foo +2 call zed@PLT so that is a good thing. * Looking past VariantKind means that the relocation selection has to use the fixup instead of the target. This is a reboot of the previous fixes for MC. I will watch the sanitizer buildbot and wait for a build before adding back the previous fixes. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204294 91177308-0d34-0410-b5e6-96231b3b80d8
* Try harder to evaluate expressions when printing assembly.Rafael Espindola2014-03-12
| | | | | | | | | When printing assembly we don't have a Layout object, but we can still try to fold some constants. Testcase by Ulrich Weigand. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203677 91177308-0d34-0410-b5e6-96231b3b80d8
* ARM: suuport .tlsdescseq directiveSaleem Abdulrasool2014-01-30
| | | | | | | | | | | This enhances the ARMAsmParser to handle .tlsdescseq directives. This is a slightly special relocation. We must be able to generate them, but not consume them in assembly. The relocation is meant to assist the linker in generating a TLS descriptor sequence. The ELF target streamer is enhanced to append additional fixups into the current segment and that is used to emit the new R_ARM_TLS_DESCSEQ relocations. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200448 91177308-0d34-0410-b5e6-96231b3b80d8
* ARM: support TLS descriptor relocationsSaleem Abdulrasool2014-01-30
| | | | | | | | Add support for tlsdesc relocations which are part of the ABI, marked as experimental. These relocations permit the linker to perform TLS reference optimizations. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200447 91177308-0d34-0410-b5e6-96231b3b80d8
* ARM: support tlscall relocationsSaleem Abdulrasool2014-01-30
| | | | | | | | | | | | | | This adds support for TLS CALL relocations. TLS CALL relocations are used to indicate to the linker to generate appropriate entries to resolve TLS references via an appropriate function invocation (e.g. __tls_get_addr(PLT)). In order to accomodate the linker relaxation of the TLS access model for the references (GD/LD -> IE, IE -> LE), the relocation addend must be incomplete. This requires that the partial inplace value is also incomplete (i.e. 0). We simply avoid the offset value calculation at the time of the fixup adjustment in the ARM assembler backend. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200446 91177308-0d34-0410-b5e6-96231b3b80d8
* ARM: add tlsldo relocationKai Nacke2014-01-20
| | | | | | | | | | Add support for the symbol(tlsldo) relocation. This is required in order to solve PR18554. Reviewed by R. Golin, A. Korobeynikov. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199644 91177308-0d34-0410-b5e6-96231b3b80d8
* Add support for parsing ARM symbol variants on ELF targetsDavid Peixotto2013-12-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ARM symbol variants are written with parens instead of @ like this: .word __GLOBAL_I_a(target1) This commit adds support for parsing these symbol variants in expressions. We introduce a new flag to MCAsmInfo that indicates the parser should use parens to parse the symbol variant. The expression parser is modified to look for symbol variants using parens instead of @ when the corresponding MCAsmInfo flag is true. The MCAsmInfo parens flag is enabled only for ARM on ELF. By adding this flag to MCAsmInfo, we are able to get rid of redundant ARM-specific symbol variants and use the generic variants instead (e.g. VK_GOT instead of VK_ARM_GOT). We use the new UseParensForSymbolVariant attribute in MCAsmInfo to correctly print the symbol variants for arm. To achive this we need to keep a handle to the MCAsmInfo in the MCSymbolRefExpr class that we can check when printing the symbol variant. Updated Tests: Changed case of symbol variant to match the generic kind. test/CodeGen/ARM/tls-models.ll test/CodeGen/ARM/tls1.ll test/CodeGen/ARM/tls2.ll test/CodeGen/Thumb2/tls1.ll test/CodeGen/Thumb2/tls2.ll PR18080 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196424 91177308-0d34-0410-b5e6-96231b3b80d8
* [PowerPC] Revert r185476 and fix up TLS variant kindsUlrich Weigand2013-07-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the commit message to r185476 I wrote: >The PowerPC-specific modifiers VK_PPC_TLSGD and VK_PPC_TLSLD >correspond exactly to the generic modifiers VK_TLSGD and VK_TLSLD. >This causes some confusion with the asm parser, since VK_PPC_TLSGD >is output as @tlsgd, which is then read back in as VK_TLSGD. > >To avoid this confusion, this patch removes the PowerPC-specific >modifiers and uses the generic modifiers throughout. (The only >drawback is that the generic modifiers are printed in upper case >while the usual convention on PowerPC is to use lower-case modifiers. >But this is just a cosmetic issue.) This was unfortunately incorrect, there is is fact another, serious drawback to using the default VK_TLSLD/VK_TLSGD variant kinds: using these causes ELFObjectWriter::RelocNeedsGOT to return true, which in turn causes the ELFObjectWriter to emit an undefined reference to _GLOBAL_OFFSET_TABLE_. This is a problem on powerpc64, because it uses the TOC instead of the GOT, and the linker does not provide _GLOBAL_OFFSET_TABLE_, so the symbol remains undefined. This means shared libraries using TLS built with the integrated assembler are currently broken. While the whole RelocNeedsGOT / _GLOBAL_OFFSET_TABLE_ situation probably ought to be properly fixed at some point, for now I'm simply reverting the r185476 commit. Now this in turn exposes the breakage of handling @tlsgd/@tlsld in the asm parser that this check-in was originally intended to fix. To avoid this regression, I'm also adding a different fix for this problem: while common code now parses @tlsgd as VK_TLSGD, a special hack in the asm parser translates this code to the platform-specific VK_PPC_TLSGD that the back-end now expects. While this is not really pretty, it's self-contained and shouldn't hurt anything else for now. One the underlying problem is fixed, this hack can be reverted again. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185945 91177308-0d34-0410-b5e6-96231b3b80d8
* [PowerPC] Remove VK_PPC_TLSGD and VK_PPC_TLSLDUlrich Weigand2013-07-02
| | | | | | | | | | | | | | | | | The PowerPC-specific modifiers VK_PPC_TLSGD and VK_PPC_TLSLD correspond exactly to the generic modifiers VK_TLSGD and VK_TLSLD. This causes some confusion with the asm parser, since VK_PPC_TLSGD is output as @tlsgd, which is then read back in as VK_TLSGD. To avoid this confusion, this patch removes the PowerPC-specific modifiers and uses the generic modifiers throughout. (The only drawback is that the generic modifiers are printed in upper case while the usual convention on PowerPC is to use lower-case modifiers. But this is just a cosmetic issue.) git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185476 91177308-0d34-0410-b5e6-96231b3b80d8
* [PowerPC] Add support for TLS data relocationsUlrich Weigand2013-07-01
| | | | | | | | | | | | This adds support for TLS data relocations and modifiers: .quad target@dtpmod .quad target@tprel .quad target@dtprel Currently exploited by the asm parser only. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185394 91177308-0d34-0410-b5e6-96231b3b80d8
* [PowerPC] Support @got modifierUlrich Weigand2013-06-25
| | | | | | | | | Add VK_... values and relocation types necessary to support the @got family of modifiers. Used by the asm parser only. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184860 91177308-0d34-0410-b5e6-96231b3b80d8
* [PowerPC] Support various tls-related modifiersUlrich Weigand2013-06-21
| | | | | | | | | | | | The current code base only supports the minimum set of tls-related relocations and @modifiers that are necessary to support compiler- generated code. This patch extends this to the full set defined in the ABI (and supported by the GNU assembler) for the benefit of the assembler parser. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184551 91177308-0d34-0410-b5e6-96231b3b80d8
* [PowerPC] Support @higher et.al. modifiersUlrich Weigand2013-06-21
| | | | | | | | | This adds support for the @higher, @highera, @highest, and @highesta modifers, including some missing relocation types. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184550 91177308-0d34-0410-b5e6-96231b3b80d8
* [PowerPC] Support @toc@h modifierUlrich Weigand2013-06-21
| | | | | | | | | This adds the relocation type and other necessary infrastructure to use the @toc@h modifier in the assembler. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184549 91177308-0d34-0410-b5e6-96231b3b80d8
* [PowerPC] Support @h modifierUlrich Weigand2013-06-21
| | | | | | | | | | | | | | This adds necessary infrastructure to support the @h modifier. Note that all required relocation types were already present (and unused). This patch provides support for using @h in the assembler; it would also be possible to now use this feature in code generated by the compiler, but this is not done yet. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184548 91177308-0d34-0410-b5e6-96231b3b80d8
* [PowerPC] Rename some more VK_PPC_ enumsUlrich Weigand2013-06-21
| | | | | | | | | | | | | | | This renames more VK_PPC_ enums, to make them more closely reflect the @modifier string they represent. This also prepares for adding a bunch of new VK_PPC_ enums in upcoming patches. For consistency, some MO_ flags related to VK_PPC_ enums are likewise renamed. No change in behaviour. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184547 91177308-0d34-0410-b5e6-96231b3b80d8
* [PowerPC] Clean up VK_PPC_TOC... namesUlrich Weigand2013-06-20
| | | | | | | | | | | | | | This is another minor cleanup; to bring enum names in line with the corresponding @modifier names, this renames: VK_PPC_TOC -> VK_PPC_TOCBASE VK_PPC_TOC_ENTRY -> VK_PPC_TOC16 No code change intended. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184491 91177308-0d34-0410-b5e6-96231b3b80d8
* [PowerPC] Clean up generation of ha16() / lo16() markersUlrich Weigand2013-05-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When targeting the Darwin assembler, we need to generate markers ha16() and lo16() to designate the high and low parts of a (symbolic) immediate. This is necessary not just for plain symbols, but also for certain symbolic expression, typically along the lines of ha16(A - B). The latter doesn't work when simply using VariantKind flags on the symbol reference. This is why the current back-end uses hacks (explicitly called out as such via multiple FIXMEs) in the symbolLo/symbolHi print methods. This patch uses target-defined MCExpr codes to represent the Darwin ha16/lo16 constructs, following along the lines of the equivalent solution used by the ARM back end to handle their :upper16: / :lower16: markers. This allows us to get rid of special handling both in the symbolLo/symbolHi print method and in the common code MCExpr::print routine. Instead, the ha16 / lo16 markers are printed simply in a custom print routine for the target MCExpr types. (As a result, the symbolLo/symbolHi print methods can now replaced by a single printS16ImmOperand routine that also handles symbolic operands.) The patch also provides a EvaluateAsRelocatableImpl routine to handle ha16/lo16 constructs. This is not actually used at the moment by any in-tree code, but is provided as it makes merging into David Fang's out-of-tree Mach-O object writer simpler. Since there is no longer any need to treat VK_PPC_GAS_HA16 and VK_PPC_DARWIN_HA16 differently, they are merged into a single VK_PPC_ADDR16_HA (and likewise for the _LO16 types). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182616 91177308-0d34-0410-b5e6-96231b3b80d8
* [PowerPC] Parse platform-specifc variant kinds in AsmParserUlrich Weigand2013-05-03
| | | | | | | | | | | This patch adds support for PowerPC platform-specific variant kinds in MCSymbolRefExpr::getVariantKindForName, and also adds a test case to verify they are translated to the appropriate fixup type. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181053 91177308-0d34-0410-b5e6-96231b3b80d8
* Fix section relocation for SECTIONREL32 with immediate offset.Rafael Espindola2013-04-25
| | | | | | Patch by Kai Nacke. This matches the gnu as output. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180568 91177308-0d34-0410-b5e6-96231b3b80d8
* MC: Support COFF image-relative MCSymbolRefsNico Rieck2013-04-10
| | | | | | | | | | | | | | | | Add support for the COFF relocation types IMAGE_REL_I386_DIR32NB and IMAGE_REL_AMD64_ADDR32NB for 32- and 64-bit respectively. These are similar to normal 4-byte relocations except that they do not include the base address of the image. Image-relative relocations are used for debug information (32-bit) and SEH unwind tables (64-bit). A new MCSymbolRef variant called 'VK_COFF_IMGREL32' is introduced to specify such relocations. For AT&T assembly, this variant can be accessed using the symbol suffix '@imgrel'. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179240 91177308-0d34-0410-b5e6-96231b3b80d8
* Change '@SECREL' suffix to GAS-compatible '@SECREL32'.Benjamin Kramer2013-03-30
| | | | | | | | | | '@SECREL' is what is used by the Microsoft assembler, but GNU as expects '@SECREL32'. With the patch, the MC-generated code works fine in combination with a recent GNU as (2.23.51.20120920 here). Patch by David Nadlinger! Differential Revision: http://llvm-reviews.chandlerc.com/D429 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178427 91177308-0d34-0410-b5e6-96231b3b80d8
* This patch improves the 64-bit PowerPC InitialExec TLS support by providingBill Schmidt2012-12-14
| | | | | | | | | | | | | | | | | | | | | | | | for a wider range of GOT entries that can hold thread-relative offsets. This matches the behavior of GCC, which was not documented in the PPC64 TLS ABI. The ABI will be updated with the new code sequence. Former sequence: ld 9,x@got@tprel(2) add 9,9,x@tls New sequence: addis 9,2,x@got@tprel@ha ld 9,x@got@tprel@l(9) add 9,9,x@tls Note that a linker optimization exists to transform the new sequence into the shorter sequence when appropriate, by replacing the addis with a nop and modifying the base register and relocation type of the ld. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170209 91177308-0d34-0410-b5e6-96231b3b80d8
* This patch implements local-dynamic TLS model support for the 64-bitBill Schmidt2012-12-12
| | | | | | | | | | | | | | | | | | | | | | | PowerPC target. This is the last of the four models, so we now have full TLS support. This is mostly a straightforward extension of the general dynamic model. I had to use an additional Chain operand to tie ADDIS_DTPREL_HA to the register copy following ADDI_TLSLD_L; otherwise everything above the ADDIS_DTPREL_HA appeared dead and was removed. As before, there are new test cases to test the assembly generation, and the relocations output during integrated assembly. The expected code gen sequence can be read in test/CodeGen/PowerPC/tls-ld.ll. There are a couple of things I think can be done more efficiently in the overall TLS code, so there will likely be a clean-up patch forthcoming; but for now I want to be sure the functionality is in place. Bill git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170003 91177308-0d34-0410-b5e6-96231b3b80d8
* Add ARM NONE and PREL31 relocation types.Logan Chien2012-12-12
| | | | | | | | | | Add R_ARM_NONE and R_ARM_PREL31 relocation types to MCExpr. Both of them will be used while generating .ARM.extab and .ARM.exidx sections. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169965 91177308-0d34-0410-b5e6-96231b3b80d8
* This patch implements the general dynamic TLS model for 64-bit PowerPC.Bill Schmidt2012-12-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Given a thread-local symbol x with global-dynamic access, the generated code to obtain x's address is: Instruction Relocation Symbol addis ra,r2,x@got@tlsgd@ha R_PPC64_GOT_TLSGD16_HA x addi r3,ra,x@got@tlsgd@l R_PPC64_GOT_TLSGD16_L x bl __tls_get_addr(x@tlsgd) R_PPC64_TLSGD x R_PPC64_REL24 __tls_get_addr nop <use address in r3> The implementation borrows from the medium code model work for introducing special forms of ADDIS and ADDI into the DAG representation. This is made slightly more complicated by having to introduce a call to the external function __tls_get_addr. Using the full call machinery is overkill and, more importantly, makes it difficult to add a special relocation. So I've introduced another opcode GET_TLS_ADDR to represent the function call, and surrounded it with register copies to set up the parameter and return value. Most of the code is pretty straightforward. I ran into one peculiarity when I introduced a new PPC opcode BL8_NOP_ELF_TLSGD, which is just like BL8_NOP_ELF except that it takes another parameter to represent the symbol ("x" above) that requires a relocation on the call. Something in the TblGen machinery causes BL8_NOP_ELF and BL8_NOP_ELF_TLSGD to be treated identically during the emit phase, so this second operand was never visited to generate relocations. This is the reason for the slightly messy workaround in PPCMCCodeEmitter.cpp:getDirectBrEncoding(). Two new tests are included to demonstrate correct external assembly and correct generation of relocations using the integrated assembler. Comments welcome! Thanks, Bill git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169910 91177308-0d34-0410-b5e6-96231b3b80d8
* This patch introduces initial-exec model support for thread-local storageBill Schmidt2012-12-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | on 64-bit PowerPC ELF. The patch includes code to handle external assembly and MC output with the integrated assembler. It intentionally does not support the "old" JIT. For the initial-exec TLS model, the ABI requires the following to calculate the address of external thread-local variable x: Code sequence Relocation Symbol ld 9,x@got@tprel(2) R_PPC64_GOT_TPREL16_DS x add 9,9,x@tls R_PPC64_TLS x The register 9 is arbitrary here. The linker will replace x@got@tprel with the offset relative to the thread pointer to the generated GOT entry for symbol x. It will replace x@tls with the thread-pointer register (13). The two test cases verify correct assembly output and relocation output as just described. PowerPC-specific selection node variants are added for the two instructions above: LD_GOT_TPREL and ADD_TLS. These are inserted when an initial-exec global variable is encountered by PPCTargetLowering::LowerGlobalTLSAddress(), and later lowered to machine instructions LDgotTPREL and ADD8TLS. LDgotTPREL is a pseudo that uses the same LDrs support added for medium code model's LDtocL, with a different relocation type. The rest of the processing is straightforward. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169281 91177308-0d34-0410-b5e6-96231b3b80d8
* This patch implements medium code model support for 64-bit PowerPC.Bill Schmidt2012-11-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The default for 64-bit PowerPC is small code model, in which TOC entries must be addressable using a 16-bit offset from the TOC pointer. Additionally, only TOC entries are addressed via the TOC pointer. With medium code model, TOC entries and data sections can all be addressed via the TOC pointer using a 32-bit offset. Cooperation with the linker allows 16-bit offsets to be used when these are sufficient, reducing the number of extra instructions that need to be executed. Medium code model also does not generate explicit TOC entries in ".section toc" for variables that are wholly internal to the compilation unit. Consider a load of an external 4-byte integer. With small code model, the compiler generates: ld 3, .LC1@toc(2) lwz 4, 0(3) .section .toc,"aw",@progbits .LC1: .tc ei[TC],ei With medium model, it instead generates: addis 3, 2, .LC1@toc@ha ld 3, .LC1@toc@l(3) lwz 4, 0(3) .section .toc,"aw",@progbits .LC1: .tc ei[TC],ei Here .LC1@toc@ha is a relocation requesting the upper 16 bits of the 32-bit offset of ei's TOC entry from the TOC base pointer. Similarly, .LC1@toc@l is a relocation requesting the lower 16 bits. Note that if the linker determines that ei's TOC entry is within a 16-bit offset of the TOC base pointer, it will replace the "addis" with a "nop", and replace the "ld" with the identical "ld" instruction from the small code model example. Consider next a load of a function-scope static integer. For small code model, the compiler generates: ld 3, .LC1@toc(2) lwz 4, 0(3) .section .toc,"aw",@progbits .LC1: .tc test_fn_static.si[TC],test_fn_static.si .type test_fn_static.si,@object .local test_fn_static.si .comm test_fn_static.si,4,4 For medium code model, the compiler generates: addis 3, 2, test_fn_static.si@toc@ha addi 3, 3, test_fn_static.si@toc@l lwz 4, 0(3) .type test_fn_static.si,@object .local test_fn_static.si .comm test_fn_static.si,4,4 Again, the linker may replace the "addis" with a "nop", calculating only a 16-bit offset when this is sufficient. Note that it would be more efficient for the compiler to generate: addis 3, 2, test_fn_static.si@toc@ha lwz 4, test_fn_static.si@toc@l(3) The current patch does not perform this optimization yet. This will be addressed as a peephole optimization in a later patch. For the moment, the default code model for 64-bit PowerPC will remain the small code model. We plan to eventually change the default to medium code model, which matches current upstream GCC behavior. Note that the different code models are ABI-compatible, so code compiled with different models will be linked and execute correctly. I've tested the regression suite and the application/benchmark test suite in two ways: Once with the patch as submitted here, and once with additional logic to force medium code model as the default. The tests all compile cleanly, with one exception. The mandel-2 application test fails due to an unrelated ABI compatibility with passing complex numbers. It just so happens that small code model was incredibly lucky, in that temporary values in floating-point registers held the expected values needed by the external library routine that was called incorrectly. My current thought is to correct the ABI problems with _Complex before making medium code model the default, to avoid introducing this "regression." Here are a few comments on how the patch works, since the selection code can be difficult to follow: The existing logic for small code model defines three pseudo-instructions: LDtoc for most uses, LDtocJTI for jump table addresses, and LDtocCPT for constant pool addresses. These are expanded by SelectCodeCommon(). The pseudo-instruction approach doesn't work for medium code model, because we need to generate two instructions when we match the same pattern. Instead, new logic in PPCDAGToDAGISel::Select() intercepts the TOC_ENTRY node for medium code model, and generates an ADDIStocHA followed by either a LDtocL or an ADDItocL. These new node types correspond naturally to the sequences described above. The addis/ld sequence is generated for the following cases: * Jump table addresses * Function addresses * External global variables * Tentative definitions of global variables (common linkage) The addis/addi sequence is generated for the following cases: * Constant pool entries * File-scope static global variables * Function-scope static variables Expanding to the two-instruction sequences at select time exposes the instructions to subsequent optimization, particularly scheduling. The rest of the processing occurs at assembly time, in PPCAsmPrinter::EmitInstruction. Each of the instructions is converted to a "real" PowerPC instruction. When a TOC entry needs to be created, this is done here in the same manner as for the existing LDtoc, LDtocJTI, and LDtocCPT pseudo-instructions (I factored out a new routine to handle this). I had originally thought that if a TOC entry was needed for LDtocL or ADDItocL, it would already have been generated for the previous ADDIStocHA. However, at higher optimization levels, the ADDIStocHA may appear in a different block, which may be assembled textually following the block containing the LDtocL or ADDItocL. So it is necessary to include the possibility of creating a new TOC entry for those two instructions. Note that for LDtocL, we generate a new form of LD called LDrs. This allows specifying the @toc@l relocation for the offset field of the LD instruction (i.e., the offset is replaced by a SymbolLo relocation). When the peephole optimization described above is added, we will need to do similar things for all immediate-form load and store operations. The seven "mcm-n.ll" test cases are kept separate because otherwise the intermingling of various TOC entries and so forth makes the tests fragile and hard to understand. The above assumes use of an external assembler. For use of the integrated assembler, new relocations are added and used by PPCELFObjectWriter. Testing is done with "mcm-obj.ll", which tests for proper generation of the various relocations for the same sequences tested with the external assembler. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168708 91177308-0d34-0410-b5e6-96231b3b80d8
* Add relocations used for mips big GOT.Akira Hatanaka2012-11-21
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168448 91177308-0d34-0410-b5e6-96231b3b80d8
* Add ARM TARGET2 relocation. The testcase will follow with actualy use-case.Anton Korobeynikov2012-11-09
| | | | | | | Based on the patch by Logan Chien! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167633 91177308-0d34-0410-b5e6-96231b3b80d8
* Rename virtual table anchors from Anchor() to anchor() for consistency with ↵Craig Topper2012-09-26
| | | | | | the rest of the tree. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164666 91177308-0d34-0410-b5e6-96231b3b80d8
* Release build: guard dump functions withManman Ren2012-09-12
| | | | | | | | | "#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)" No functional change. Update r163344. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163679 91177308-0d34-0410-b5e6-96231b3b80d8
* Release build: guard dump functions with "ifndef NDEBUG"Manman Ren2012-09-06
| | | | | | | No functional change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163344 91177308-0d34-0410-b5e6-96231b3b80d8
* Lower constant pools and jump tables via TOC on PPC64/SVR4.Roman Divacky2012-08-24
| | | | | | | In collaboration with Adhemerval Zanella. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162562 91177308-0d34-0410-b5e6-96231b3b80d8
* Add VK_Mips_HIGHER and VK_Mips_HIGHEST to MCSymbolRefExpr::VariantKind.Akira Hatanaka2012-07-21
| | | | | | | Test case will be added later when long branch patch is checked in. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160597 91177308-0d34-0410-b5e6-96231b3b80d8
* Implement local-exec TLS on PowerPC.Roman Divacky2012-06-04
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157935 91177308-0d34-0410-b5e6-96231b3b80d8
* Prune some includes and forward declarations.Craig Topper2012-03-26
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153429 91177308-0d34-0410-b5e6-96231b3b80d8
* ARM Thumb symbol references in assembly need the low bit set.Jim Grosbach2012-02-24
| | | | | | | | | Add support for a missed case when the symbols in a difference expression are in the same section but not the same fragment. rdar://10924681 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151345 91177308-0d34-0410-b5e6-96231b3b80d8
* Add support for implicit TLS model used with MS VC runtime.Anton Korobeynikov2012-02-11
| | | | | | | Patch by Kai Nacke! git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150307 91177308-0d34-0410-b5e6-96231b3b80d8
* Convert assert(0) to llvm_unreachableCraig Topper2012-02-07
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149967 91177308-0d34-0410-b5e6-96231b3b80d8
* Add support for the R_ARM_TARGET1 relocation, which should be given to ↵James Molloy2012-01-26
| | | | | | | | | | relocations applied to all C++ constructors and destructors. This enables the linker to match concrete relocation types (absolute or relative) with whatever library or C++ support code is being linked against. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149057 91177308-0d34-0410-b5e6-96231b3b80d8
* Add 'llvm_unreachable' to passify GCC's understanding of the constraintsChandler Carruth2012-01-10
| | | | | | | | of several newly un-defaulted switches. This also helps optimizers (including LLVM's) recognize that every case is covered, and we should assume as much. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147861 91177308-0d34-0410-b5e6-96231b3b80d8
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