Add the commandline options -fprofile-instr-generate[=filename] and -profile-instr-use=filename
-fprofile-instr-generate
-- Add instrumentation on branches, switches, and function entry; uses LLVM's InstrProf pass.
-- Link to profile runtime that writes instrumentation counters to a file.
-fprofile-instr-use
-- Read profile data from a file and apply branch weights to branches and switches, and annotate functions with entrycount in LLVM IR.
-- Functions with low or high entrycount are marked with 'cold' or 'inlinehint'.
The only statement type without PGO yet is "try-finally".
A new pragma, `pragma(LDC_profile_instr, [ true | false ])`, is added to selectively disable/enable instrumentation of functions (granularity = whole functions).
The runtime library ldc-profile-rt is a copy of LLVM compiler-rt lib/profile. It has to be exactly in-sync with the LLVM version, and thus we need a copy for each PGO-supported LLVM (>=3.7).
import ldc.profile for a D interface to ldc-profile-rt (for example to reset execution counts after a program startup phase).
The instrumentation data is mainly passed on to LLVM: function-entry counts and branch counts/probabilities. LDC marks functions as hot when "execution count is 30% of the maximum function execution count", and marks functions as cold if their count is 1% of maximum function execution count.
The source of LLVM's llvm-profdata tool is hereby included in LDCs repository (different source for each LLVM version), and the binary is included in the install bin folder.
The executable is named "ldc-profdata" to avoid clashing with llvm-profdata on the same machine. This is needed because profdata executable has to be in-sync with the LLVM version used to build LDC.
Maintenance burden: for trunk LLVM, we have to keep ldc-profile-rt and llvm-profdata in sync. There is no diff with upstream; but because of active development there are the occasional API changes.
Windows x64 ABI: remove unnecessary \01 from mangled symbol name.
This removes the 0x1 byte from `.mangleof` accessible from user code.
Resolves issue #1519
Also let mangleForLLVM take a std::string, to enable C++11's moves.
The temporary files created should be unique for parallel processes (e.g. in a test suite where LDC is called in parallel with perhaps same input).
These files will be deleted after execution so their name is not relevant. For better linking errors, the new filenames are created by appending random characters to their name.
Also adds the CMake infrastructure to compile and link the D source files.
The build is partially broken:
- A few files in Phobos and druntime do not build
- MSVC build is broken because of unresolved symbols involving reals
This PR replaces the few uses of global.params.is<OS> with
global.params.targetTriple.isOS<OS>(). This avoids adding a new
boolean for each supported OS.
It also defines all xBSD-type OS as using the dso-registry.
Now with *almost* working EH codegen. Does not compile Phobos yet
because we run into the "instruction does not dominate all uses"
issue when an r-value result of toElemDtor is used and we need to
run cleanups in between. Should easily be fixed by promoting those
values to allocas.
Most of the changes outside of ir/irfunction.{h, cpp} are just
because CreateCallOrInvoke moved locations. I took the
opportunity to also make use of the different arg count
overloads where possible.
In case of a singleobj build and a provided output file (.exe or .obj).
The dmd-testsuite tests used to produce lots of .o files while expecting
.obj ones as specified in the command line.
0.15.1 used stdcall convention everywhere. But the ABI change in 0.15.2
requires use of the C calling convention for variadic calls on x86
because the stdcall convention does not support vararg functions.
Solution is to check the llvm::FunctionType if the function has varargs.
This commit also makes the C calling convention the global default
because according to the LLVM documentation the fastcc convention used
for D linkage does not support varargs.
This fixes issue #1000.
This is likely an LLVM bug: The code in InlineFunctions.cpp
only updates the source location metadata for the instructions
in the inlined callee when the call site has a source location
set. When the caller has no location metadata, the scope for
the inlined instructions thus still points to the DISubprogram
for the original callee. This then leads to an assertion during
codegen.
GitHub: Fixes#998.
If a target file name is given (`-of`) and a library is created then
`-singleObj` is implied. This results in behaviour not compatible
with dmd. This commit checks for this situation and does not set
`-singleObj`. This fixes issue #978.
- Do not create debug info after we called finalize.
- Clean up debug info generation for module ctor/dtor.
- Rename EmitSubProgramInternal() to EmitModuleCTor().
- Remove unused parameter from CreateTypeDescription().
