https://github.com/rust-lang/rust http://git.dreamy.place/mirrors/rust/atom?h=1.22.0 2017-09-30T07:22:15+00:00 2017-09-30T07:22:15+00:00 Alex Crichton alex@alexcrichton.com 2017-07-23T15:14:38+00:00 urn:sha1:ded38dbfc258f8e253ab61d1bca08b21efa2bf3d This commit is a refactoring of the LTO backend in Rust to support compilations with multiple codegen units. The immediate result of this PR is to remove the artificial error emitted by rustc about `-C lto -C codegen-units-8`, but longer term this is intended to lay the groundwork for LTO with incremental compilation and ultimately be the underpinning of ThinLTO support. The problem here that needed solving is that when rustc is producing multiple codegen units in one compilation LTO needs to merge them all together. Previously only upstream dependencies were merged and it was inherently relied on that there was only one local codegen unit. Supporting this involved refactoring the optimization backend architecture for rustc, namely splitting the `optimize_and_codegen` function into `optimize` and `codegen`. After an LLVM module has been optimized it may be blocked and queued up for LTO, and only after LTO are modules code generated. Non-LTO compilations should look the same as they do today backend-wise, we'll spin up a thread for each codegen unit and optimize/codegen in that thread. LTO compilations will, however, send the LLVM module back to the coordinator thread once optimizations have finished. When all LLVM modules have finished optimizing the coordinator will invoke the LTO backend, producing a further list of LLVM modules. Currently this is always a list of one LLVM module. The coordinator then spawns further work to run LTO and code generation passes over each module. In the course of this refactoring a number of other pieces were refactored: * Management of the bytecode encoding in rlibs was centralized into one module instead of being scattered across LTO and linking. * Some internal refactorings on the link stage of the compiler was done to work directly from `CompiledModule` structures instead of lists of paths. * The trans time-graph output was tweaked a little to include a name on each bar and inflate the size of the bars a little 2017-07-21T17:09:10+00:00 Alex Crichton alex@alexcrichton.com 2017-07-21T16:15:03+00:00 urn:sha1:b022d54641586ae1de72cd6325eb09aee7753cca 2017-07-21T17:09:10+00:00 Tim Neumann mail@timnn.me 2017-07-21T12:29:23+00:00 urn:sha1:1ee87b3765b4cc0ab78aec25009e4e5295024f93 2017-07-21T12:32:00+00:00 Tim Neumann mail@timnn.me 2017-07-21T12:02:52+00:00 urn:sha1:a53676762bbe492154926393b187f0ee49df6e98 2017-07-21T12:31:54+00:00 Tim Neumann mail@timnn.me 2017-07-21T11:31:19+00:00 urn:sha1:48424c97490b3a449c57d8540529af4971386c4a 2017-07-21T12:31:51+00:00 Tim Neumann mail@timnn.me 2017-07-21T11:26:41+00:00 urn:sha1:5f9e432534d54aebc2fa45f83becd13bccafa2d7 2017-07-21T12:31:46+00:00 Tim Neumann mail@timnn.me 2017-07-21T11:15:36+00:00 urn:sha1:2c9c8dc5f46bd2db5a5b81acca72a23de75502ec 2017-06-04T14:54:39+00:00 Marco Castelluccio mcastelluccio@mozilla.com 2017-06-04T14:54:39+00:00 urn:sha1:ecba8d6a23d8bafd6296d619180a5f3e09bb21b1 2017-05-28T07:43:24+00:00 Ariel Ben-Yehuda ariel.byd@gmail.com 2017-05-18T15:43:52+00:00 urn:sha1:7b295eea4296eedf7858a001297eadfaace253d3 2017-05-01T09:16:20+00:00 whitequark whitequark@whitequark.org 2017-02-13T09:57:50+00:00 urn:sha1:42754ce710a777b38402b12728daf54d68ea2b50 When -Z profile is passed, the GCDAProfiling LLVM pass is added to the pipeline, which uses debug information to instrument the IR. After compiling with -Z profile, the $(OUT_DIR)/$(CRATE_NAME).gcno file is created, containing initial profiling information. After running the program built, the $(OUT_DIR)/$(CRATE_NAME).gcda file is created, containing branch counters. The created *.gcno and *.gcda files can be processed using the "llvm-cov gcov" and "lcov" tools. The profiling data LLVM generates does not faithfully follow the GCC's format for *.gcno and *.gcda files, and so it will probably not work with other tools (such as gcov itself) that consume these files.