summaryrefslogtreecommitdiff
path: root/compiler/nativeGen/Dwarf.hs
Commit message (Collapse)AuthorAgeFilesLines
* Don't refer to blocks in debug info when -g1Bartosz Nitka2018-03-251-2/+9
| | | | | | | | | | | | | | | | | | | | -g1 removes block information, but it turns out that procs can refer to block information through parents. Note [Splitting DebugBlocks] explains the parentage relationship. Test Plan: * ./validate * added a new test Reviewers: bgamari, simonmar Reviewed By: bgamari Subscribers: rwbarton, thomie, carter GHC Trac Issues: #14894 Differential Revision: https://phabricator.haskell.org/D4496
* Get rid of some stuttering in comments and docsGabor Greif2017-12-191-1/+1
|
* compiler: introduce custom "GhcPrelude" PreludeHerbert Valerio Riedel2017-09-191-0/+2
| | | | | | | | | | | | | | | | | | This switches the compiler/ component to get compiled with -XNoImplicitPrelude and a `import GhcPrelude` is inserted in all modules. This is motivated by the upcoming "Prelude" re-export of `Semigroup((<>))` which would cause lots of name clashes in every modulewhich imports also `Outputable` Reviewers: austin, goldfire, bgamari, alanz, simonmar Reviewed By: bgamari Subscribers: goldfire, rwbarton, thomie, mpickering, bgamari Differential Revision: https://phabricator.haskell.org/D3989
* Hoopl: remove dependency on Hoopl packageMichal Terepeta2017-06-231-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This copies the subset of Hoopl's functionality needed by GHC to `cmm/Hoopl` and removes the dependency on the Hoopl package. The main motivation for this change is the confusing/noisy interface between GHC and Hoopl: - Hoopl has `Label` which is GHC's `BlockId` but different than GHC's `CLabel` - Hoopl has `Unique` which is different than GHC's `Unique` - Hoopl has `Unique{Map,Set}` which are different than GHC's `Uniq{FM,Set}` - GHC has its own specialized copy of `Dataflow`, so `cmm/Hoopl` is needed just to filter the exposed functions (filter out some of the Hoopl's and add the GHC ones) With this change, we'll be able to simplify this significantly. It'll also be much easier to do invasive changes (Hoopl is a public package on Hackage with users that depend on the current behavior) This should introduce no changes in functionality - it merely copies the relevant code. Signed-off-by: Michal Terepeta <michal.terepeta@gmail.com> Test Plan: ./validate Reviewers: austin, bgamari, simonmar Reviewed By: bgamari, simonmar Subscribers: simonpj, kavon, rwbarton, thomie Differential Revision: https://phabricator.haskell.org/D3616
* Cmm: Add support for undefined unwinding statementsBen Gamari2017-02-081-1/+3
| | | | | | | | | | | | | | And use to mark `stg_stack_underflow_frame`, which we are unable to determine a caller from. To simplify parsing at the moment we steal the `return` keyword to indicate an undefined unwind value. Perhaps this should be revisited. Reviewers: scpmw, simonmar, austin, erikd Subscribers: dfeuer, thomie Differential Revision: https://phabricator.haskell.org/D2738
* Generalize CmmUnwind and pass unwind information through NCGBen Gamari2017-02-081-10/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As discussed in D1532, Trac Trac #11337, and Trac Trac #11338, the stack unwinding information produced by GHC is currently quite approximate. Essentially we assume that register values do not change at all within a basic block. While this is somewhat true in normal Haskell code, blocks containing foreign calls often break this assumption. This results in unreliable call stacks, especially in the code containing foreign calls. This is worse than it sounds as unreliable unwinding information can at times result in segmentation faults. This patch set attempts to improve this situation by tracking unwinding information with finer granularity. By dispensing with the assumption of one unwinding table per block, we allow the compiler to accurately represent the areas surrounding foreign calls. Towards this end we generalize the representation of unwind information in the backend in three ways, * Multiple CmmUnwind nodes can occur per block * CmmUnwind nodes can now carry unwind information for multiple registers (while not strictly necessary; this makes emitting unwinding information a bit more convenient in the compiler) * The NCG backend is given an opportunity to modify the unwinding records since it may need to make adjustments due to, for instance, native calling convention requirements for foreign calls (see #11353). This sets the stage for resolving #11337 and #11338. Test Plan: Validate Reviewers: scpmw, simonmar, austin, erikd Subscribers: qnikst, thomie Differential Revision: https://phabricator.haskell.org/D2741
* Replace calls to `ptext . sLit` with `text`Jan Stolarek2016-01-181-4/+3
| | | | | | | | | | | | | | | | | | | | Summary: In the past the canonical way for constructing an SDoc string literal was the composition `ptext . sLit`. But for some time now we have function `text` that does the same. Plus it has some rules that optimize its runtime behaviour. This patch takes all uses of `ptext . sLit` in the compiler and replaces them with calls to `text`. The main benefits of this patch are clener (shorter) code and less dependencies between module, because many modules now do not need to import `FastString`. I don't expect any performance benefits - we mostly use SDocs to report errors and it seems there is little to be gained here. Test Plan: ./validate Reviewers: bgamari, austin, goldfire, hvr, alanz Subscribers: goldfire, thomie, mpickering Differential Revision: https://phabricator.haskell.org/D1784
* Output source notes in extended DWARF DIEsBen Gamari2015-11-231-10/+21
| | | | | | | | In order to accomplish this we need to ensure that emit DIEs for all DebugBlocks, even those that have been optimized out, lest we end up with undefined symbols of parents at link time. Differential Revision: https://phabricator.haskell.org/D1279
* Dwarf: Ensure tick parentage is preservedBen Gamari2015-11-231-8/+42
| | | | Differential Revision: https://phabricator.haskell.org/D1387
* Support multiple debug output levelsBen Gamari2015-11-231-3/+4
| | | | | | | | | We now only strip block information from DebugBlocks when compiling with `-g1`, intended to be used when only minimal debug information is desired. `-g2` is assumed when `-g` is passed without any integer argument. Differential Revision: https://phabricator.haskell.org/D1281
* Implement function-sections for Haskell code, #8405Simon Brenner2015-11-121-2/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds a flag -split-sections that does similar things to -split-objs, but using sections in single object files instead of relying on the Satanic Splitter and other abominations. This is very similar to the GCC flags -ffunction-sections and -fdata-sections. The --gc-sections linker flag, which allows unused sections to actually be removed, is added to all link commands (if the linker supports it) so that space savings from having base compiled with sections can be realized. Supported both in LLVM and the native code-gen, in theory for all architectures, but really tested on x86 only. In the GHC build, a new SplitSections variable enables -split-sections for relevant parts of the build. Test Plan: validate with both settings of SplitSections Reviewers: dterei, Phyx, austin, simonmar, thomie, bgamari Reviewed By: simonmar, thomie, bgamari Subscribers: hsyl20, erikd, kgardas, thomie Differential Revision: https://phabricator.haskell.org/D1242 GHC Trac Issues: #8405
* Dwarf: Produce .dwarf_aranges sectionBen Gamari2015-08-291-10/+18
| | | | | | | | | | Test Plan: Check with `readelf --debug-dump=ranges` Reviewers: scpmw, austin Subscribers: thomie Differential Revision: https://phabricator.haskell.org/D1174
* Dwarf: Produce {low,high}_pc attributes for compilation unitsBen Gamari2015-08-291-1/+5
| | | | | | | | | | | | | Some libraries (e.g. elfutils) need these otherwise they ignore our DWARF annotations. Test Plan: Test with elfutils' `readelf --debug-dump=cu_index` Reviewers: scpmw, austin Subscribers: thomie Differential Revision: https://phabricator.haskell.org/D1173
* Fix DWARF generation for MinGW (#10468)Peter Wortmann2015-06-111-1/+1
| | | | | | | Fortunately this is relatively straightforward - all we need to do is switch to a non-ELF-specific way of specifying object file sections and make sure that section-relative addresses work correctly. This is enough to make "gdb" work on MinGW builds.
* Restore unwind information generationPeter Wortmann2015-04-031-2/+2
| | | | | | | | | | | | | | | | While we want to reduce the amount of information generated into debug_info, it really doesn't make sense to remove block information for unwinding. This is a simple oversight introduced in 4ab57024, which severly reduces the usefulness of generated unwind data. Thanks to bitonic for spotting this! Reviewed By: austin Differential Revision: https://phabricator.haskell.org/D792 GHC Trac Issues: #10236
* Dwarf generation fixed pt 2Peter Wortmann2015-01-131-1/+4
| | | | | | | | | - Don't bracket HsTick expression uneccessarily - Generate debug information in UTF8 - Reduce amount of information generated - we do not currently need block information, for example. Special thanks to slyfox for the reports!
* Some Dwarf generation fixesPeter Wortmann2014-12-181-2/+2
| | | | | | | | - Make abbrev offset absolute on Non-Mac systems - Add another termination byte at the end of the abbrev section (readelf complains) - Scope combination was wrong for the simpler cases - Shouldn't have a "global/" in front of all scopes
* Generate DWARF unwind informationPeter Wortmann2014-12-161-1/+44
| | | | | | | | | | | | | | | | | | | | | | | | | | This tells debuggers such as GDB how to "unwind" a program state, which allows them to walk the stack up. Notes: * The code is quite general, perhaps unnecessarily so. Unless we get more unwind information, only the first case of pprSetUnwind will get used - and pprUnwindExpr and pprUndefUnwind will never be called. It just so happens that this is a point where we can get a lot of features cheaply, even if we don't use them. * When determining what location to show for a return address, most debuggers check the map for "rip-1", assuming that's where the "call" instruction is. For tables-next-to-code, that happens to always be the end of an info table. We therefore cheat a bit here by shifting .debug_frame information so it covers the end of the info table, as well as generating a .loc directive for the info table data. Debuggers will still show the wrong label for the return address, though. Haven't found a way around that one yet. (From Phabricator D396)
* Generate DWARF info sectionPeter Wortmann2014-12-161-0/+120
This is where we actually make GHC emit DWARF code. The info section contains all the general meta information bits as well as an entry for every block of native code. Notes: * We need quite a few new labels in order to properly address starts and ends of blocks. * Thanks to Nathan Howell for taking the iniative to get our own Haskell language ID for DWARF! (From Phabricator D396)
View Lorry Controller Status