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ac03e736c7
specified in the same file that the library itself is created. This is more idiomatic for CMake builds, and also allows us to correctly specify dependencies that are missed due to bugs in the GenLibDeps perl script, or change from compiler to compiler. On Linux, this returns CMake to a place where it can relably rebuild several targets of LLVM. I have tried not to change the dependencies from the ones in the current auto-generated file. The only places I've really diverged are in places where I was seeing link failures, and added a dependency. The goal of this patch is not to start changing the dependencies, merely to move them into the correct location, and an explicit form that we can control and change when necessary. This also removes a serialization point in the build because we don't have to scan all the libraries before we begin building various tools. We no longer have a step of the build that regenerates a file inside the source tree. A few other associated cleanups fall out of this. This isn't really finished yet though. After talking to dgregor he urged switching to a single CMake macro to construct libraries with both sources and dependencies in the arguments. Migrating from the two macros to that style will be a follow-up patch. Also, llvm-config is still generated with GenLibDeps.pl, which means it still has slightly buggy dependencies. The internal CMake 'llvm-config-like' macro uses the correct explicitly specified dependencies however. A future patch will switch llvm-config generation (when using CMake) to be based on these deps as well. This may well break Windows. I'm getting a machine set up now to dig into any failures there. If anyone can chime in with problems they see or ideas of how to solve them for Windows, much appreciated. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136433 91177308-0d34-0410-b5e6-96231b3b80d8
Analysis Opportunities:
//===---------------------------------------------------------------------===//
In test/Transforms/LoopStrengthReduce/quadradic-exit-value.ll, the
ScalarEvolution expression for %r is this:
{1,+,3,+,2}<loop>
Outside the loop, this could be evaluated simply as (%n * %n), however
ScalarEvolution currently evaluates it as
(-2 + (2 * (trunc i65 (((zext i64 (-2 + %n) to i65) * (zext i64 (-1 + %n) to i65)) /u 2) to i64)) + (3 * %n))
In addition to being much more complicated, it involves i65 arithmetic,
which is very inefficient when expanded into code.
//===---------------------------------------------------------------------===//
In formatValue in test/CodeGen/X86/lsr-delayed-fold.ll,
ScalarEvolution is forming this expression:
((trunc i64 (-1 * %arg5) to i32) + (trunc i64 %arg5 to i32) + (-1 * (trunc i64 undef to i32)))
This could be folded to
(-1 * (trunc i64 undef to i32))
//===---------------------------------------------------------------------===//