While parsing of floating-point literals and CTFE still operate with the
host LDC's real type, compile-time reals can in principle be emitted in
arbitrary precision via LLVM software conversion, therefore paving the way
for cross-compilation to all targets.
The representable constants are still limited by the compile-time real_t
precision. E.g., LDC on Windows with its 64-bit reals can't hold and emit
an 80-bit `real.max` when cross-compiling to a non-Windows x86(_64)
target; the compile-time value will silently overflow to infinity and
later be emitted as 80-bit infinity.
LDC on AArch64 with its 128-bit quad-precision reals on the other hand can
hold and emit reals for all targets, making it a universal cross-compiler
with quad-precision compile-time reals in hardware.
We don't use the strange 2x64-bit PPC double-double format (see
`getRealType()` in `ir/irtype.cpp`), but would more or less support it
(the type properties (max, min_normal...) still need to be determined;
LLVM isn't sure about those either...).
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
1. Main include corresponding to .cpp file, if any.
2. DMD and LDC includes.
3. LLVM includes.
4. System includes.
Also updated a few include guards to match the default format.
Added: started support for x86 80bit floating point.
Changed: aggregates passed by value now use the llvm 'byval' parameter attribute, also lays ground work for
using other attributes.
Changed: eliminated a lot more std::vectorS, these showed up pretty much at the top when profiling!
Changed: performed other misc. cleanups.
Changed: halt expression now call the new llvm trap intrinsic instead of an assert(0).
Changed: dstress suite now passes -O0 by default, this only eliminates unreferenced globals, which speeds up
linking quite a bit.
Fixed a bunch of the built-in typeinfos for arrays, they did not inherit TypeInfo_Array.
Applied patch to tango/text/convert/Layout.d by fvbommel, closes#47 .
Cleaned up some type code.
Replaced uses of llvm::Type with LLType (a typedef), same for Value and Constant.
Fixed a few cases where typeinfo for user structs could be emitted multiple times, seems to still be some cases of this :/
