related transformations out of target-specific dag combine into the
ARM backend. These were added by Evan in r37685 with no testcases
and only seems to help ARM (e.g. test/CodeGen/ARM/select_xform.ll).
Add some simple X86-specific (for now) DAG combines that turn things
like cond ? 8 : 0 -> (zext(cond) << 3). This happens frequently
with the recently added cp constant select optimization, but is a
very general xform. For example, we now compile the second example
in const-select.ll to:
_test:
movsd LCPI2_0, %xmm0
ucomisd 8(%esp), %xmm0
seta %al
movzbl %al, %eax
movl 4(%esp), %ecx
movsbl (%ecx,%eax,4), %eax
ret
instead of:
_test:
movl 4(%esp), %eax
leal 4(%eax), %ecx
movsd LCPI2_0, %xmm0
ucomisd 8(%esp), %xmm0
cmovbe %eax, %ecx
movsbl (%ecx), %eax
ret
This passes multisource and dejagnu.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66779 91177308-0d34-0410-b5e6-96231b3b80d8
linkage: this linkage type only applies to declarations,
but ODR is only relevant to globals with definitions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66650 91177308-0d34-0410-b5e6-96231b3b80d8
and extern_weak_odr. These are the same as the non-odr versions,
except that they indicate that the global will only be overridden
by an *equivalent* global. In C, a function with weak linkage can
be overridden by a function which behaves completely differently.
This means that IP passes have to skip weak functions, since any
deductions made from the function definition might be wrong, since
the definition could be replaced by something completely different
at link time. This is not allowed in C++, thanks to the ODR
(One-Definition-Rule): if a function is replaced by another at
link-time, then the new function must be the same as the original
function. If a language knows that a function or other global can
only be overridden by an equivalent global, it can give it the
weak_odr linkage type, and the optimizers will understand that it
is alright to make deductions based on the function body. The
code generators on the other hand map weak and weak_odr linkage
to the same thing.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66339 91177308-0d34-0410-b5e6-96231b3b80d8
the same say the "test" instruction does in overflow cases,
so eliminating the test is only safe when those bits aren't
needed, as is the case for COND_E and COND_NE, or if it
can be proven that no overflow will occur. For now, just
restrict the optimization to COND_E and COND_NE and don't
do any overflow analysis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66318 91177308-0d34-0410-b5e6-96231b3b80d8
INC64_32r and INC64_16r, because these instructions are encoded
differently on x86-64. This fixes JIT regressions on x86-64 in
kimwitu++ and others.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66207 91177308-0d34-0410-b5e6-96231b3b80d8
of MachineInstr def operands must be subtracted out. This bug
was uncovered by the recent x86 EFLAGS optimization. Before
that, the only instructions that ever needed unfolding were
things like CMP32rm, where NumDefs is zero.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66056 91177308-0d34-0410-b5e6-96231b3b80d8
arbitrary vector sizes. Add an optional MinSplatBits parameter to specify
a minimum for the splat element size. Update the PPC target to use the
revised interface.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65899 91177308-0d34-0410-b5e6-96231b3b80d8
possibly for the reason suggested by the comment.
No wonder it didn't work very well. This unblocks
bootstrap with assertions on ppc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65601 91177308-0d34-0410-b5e6-96231b3b80d8
results via reference parameters.
This patch also appears to fix Evan's reported problem supplied as a
reduced bugpoint test case.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65426 91177308-0d34-0410-b5e6-96231b3b80d8
them are generic changes.
- Use the "fast" flag that's already being passed into the asm printers instead
of shoving it into the DwarfWriter.
- Instead of calling "MI->getParent()->getParent()" for every MI, set the
machine function when calling "runOnMachineFunction" in the asm printers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65379 91177308-0d34-0410-b5e6-96231b3b80d8
