"Writing an LLVM Compiler Backend" can be misinterpreted as meaning
"backend" in the sense of "using LLVM as a backend for your compiler for
your new language". This new name is less ambiguous.
As a bonus, this brings the title in line with the file name.
llvm-svn: 185377
Create a dedicated register class for floating point condition code registers and
move FCC0 from register class CCR to the new register class.
llvm-svn: 185373
When phis get lowered, destination copies are inserted using an iterator that is
determined once for all phis in the block, which BuildMI interprets as a request
to insert an instruction directly before the iterator. In the case of a cyclic
phi, source copies may also be inserted directly before this iterator, which can
cause source copies to be inserted before destination copies. The fix is to keep
an iterator to the last phi and then advance it while lowering each phi in order
to insert destination copies directly after the phis.
llvm-svn: 185363
Although you can't generate this from C on PPC64, if you have a loop using a
64-bit counter on PPC32 then you can't form a CTR-based loop for it. This had
been cauing the PPCCTRLoops pass to assert.
Thanks to Joerg Sonnenberger for providing a test case!
llvm-svn: 185361
According to the AArch64 ELF specification (4.6.8), it's the
assembler's responsibility to make sure the shift amount is correct in
relocated MOVZ/MOVK instructions.
This wasn't being obeyed by either the MCJIT CodeGen or RuntimeDyldELF
(which happened to work out well for JIT tests). This commit should
make us compliant in this area.
llvm-svn: 185360
(2) Rename llvm-cov test inputs so the string "llvm-cov" doesn't get
substituted by lit within the input filenames on the RUN line.
(3) XFAIL llvm-cov.test because it asserts:
include/llvm/ADT/SmallVector.h:140: reference llvm::SmallVectorTemplateCommon<llvm::GCOVBlock *, void>::operator[](unsigned int) [T = llvm::GCOVBlock *]: Assertion `begin() + idx < end()' failed.
llvm-svn: 185358
Turns out I'd misread the architecture reference manual and thought
that was a load/store-store barrier, when it's not.
Thanks for pointing it out Eli!
llvm-svn: 185356
A @got reference must always result in a relocation, so that
the linker has a chance to set up the GOT entry, even if the
symbol happens to be local.
Add a PPCELFObjectWriter::ExplicitRelSym routine that enforces
a relocation to be emitted for GOT references.
llvm-svn: 185353
The test case had a couple of FIXMEs where the instruction is in
fact already supported by the back-end. In some other case, while
the generic form of the instruction is not yet supported, a
specialized form is. This adds tests for those already supported
instructions / instruction forms.
llvm-svn: 185347
I believe the full "dmb ish" barrier is not required to guarantee release
semantics for atomic operations. The weaker "dmb ishst" prevents previous
operations being reordered with a store executed afterwards, which is enough.
A key point to note (fortunately already correct) is that this barrier alone is
*insufficient* for sequential consistency, no matter how liberally placed.
llvm-svn: 185339
We are using virtual registers throughout now, but we still need
to keep a few physical registers per class around to keep the
infrastructure happy.
llvm-svn: 185334
Fix a case where we were incorrectly sign-extending a value when we should have been zero-extending the value.
Also change some SIGN_EXTEND to ANY_EXTEND because we really dont care and may have more opportunity to fold subexpressions
llvm-svn: 185331
This kind of simplification is sometimes useful, but in general it's not correct.
As GNU/kFreeBSD is an hybrid system, for kernel-related issues we want to match the
build definitions used for FreeBSD, whereas for userland-related issues we want to
match the definitions used for other systems with Glibc.
The current modification adjusts the build system so that they can be distinguished,
and explicitly adds GNU/kFreeBSD to the build checks in which it belongs.
Fixes bug #16444.
Patch by Robert Millan in the context of Debian.
llvm-svn: 185311
Math functions are mark as readonly because they read the floating point
rounding mode. Because we don't vectorize loops that would contain function
calls that set the rounding mode it is safe to ignore this memory read.
llvm-svn: 185299