Microoptimize Twine's with unsigned and int to not pin their value to
the stack. This saves stack space in common cases and allows mem2reg
in the caller. A simple example is:
void foo(const Twine &);
void bar(int x) {
foo("xyz: " + Twine(x));
}
Before:
__Z3bari:
subq $40, %rsp
movl %edi, 36(%rsp)
leaq L_.str3(%rip), %rax
leaq 36(%rsp), %rcx
leaq 8(%rsp), %rdi
movq %rax, 8(%rsp)
movq %rcx, 16(%rsp)
movb $3, 24(%rsp)
movb $7, 25(%rsp)
callq __Z3fooRKN4llvm5TwineE
addq $40, %rsp
ret
After:
__Z3bari:
subq $24, %rsp
leaq L_.str3(%rip), %rax
movq %rax, (%rsp)
movslq %edi, %rax
movq %rax, 8(%rsp)
movb $3, 16(%rsp)
movb $7, 17(%rsp)
leaq (%rsp), %rdi
callq __Z3fooRKN4llvm5TwineE
addq $24, %rsp
ret
It saves 16 bytes of stack and one instruction in this case.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103107 91177308-0d34-0410-b5e6-96231b3b80d8
indirect branches in all the predecessors. This avoids unnecessarily
splitting edges in cases where load PRE is not possible anyway.
Thanks to Jakub Staszak for pointing this out.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103034 91177308-0d34-0410-b5e6-96231b3b80d8
instructions which have no direct register usage.
Darwin 'as' accepts:
add $0, (%rax)
but rejects
mov $0, (%rax)
for example.
Given that, only accept suffix matches which match exactly one form. We still
need to emit nice diagnostics for failures...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103015 91177308-0d34-0410-b5e6-96231b3b80d8
- The idea is that when a match fails, we just try to match each of +'b', +'w',
+'l'. If exactly one matches, we assume this is a mnemonic prefix and accept
it. If all match, we assume it is width generic, and take the 'l' form.
- This would be a horrible hack, if it weren't so simple. Therefore it is an
elegant solution! Chris gets the credit for this particular elegant
solution. :)
- Next step to making this more robust is to have the X86 matcher generate the
mnemonic prefix information. Ideally we would also compute up-front exactly
which mnemonic to attempt to match, but this may require more custom code in
the matcher than is really worth it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103012 91177308-0d34-0410-b5e6-96231b3b80d8
buildbot: the debugging and non-debugging versions of getFunction were not
functionally equivalent: the non-debugging version wrongly assumed that if a
metadata operand was not metadata, then it had a non-null containing function.
This is not true, since the operand might be a global value, constant etc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103008 91177308-0d34-0410-b5e6-96231b3b80d8
RAUW of a global variable with a local variable in function F,
if function local metadata M in function G was using the global
then M would become function-local to both F and G, which is not
allowed. See the testcase for an example. Fixed by detecting
this situation and zapping the metadata operand when it occurs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103007 91177308-0d34-0410-b5e6-96231b3b80d8
in registers into a separate function to de-couple it from the
top-down-specific logic in getRegForValue.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102975 91177308-0d34-0410-b5e6-96231b3b80d8
to fadd, fsub, and fmul, when used with a floating-point type. LLVM
has supported the new instructions since 2.6, so it's time to get
on board.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102971 91177308-0d34-0410-b5e6-96231b3b80d8
debug output is showing machine instructions, the IR-level basic block names
aren't very meaningful, and because multiple machine basic blocks may be
derived from one IR-level BB, they're also not unique.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102960 91177308-0d34-0410-b5e6-96231b3b80d8
instructions as the Mac OS X darwin assembler. Some of which like 'fcoml'
assembled to different opcodes. While some of the suffixes were just different.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102958 91177308-0d34-0410-b5e6-96231b3b80d8
caused the a pushl instruction to be incorrectly encoding using only two bytes
of immediate, causing the following 2 instruction bytes to be part of the 32-bit
immediate value. Also fixed the one byte form of push to be used when the
immediate would fit in a signed extended byte. Lastly changed the names to not
include the 32 of PUSH32 since they actually push the size of the stack pointer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102951 91177308-0d34-0410-b5e6-96231b3b80d8
Also, pass true for isSigned even when creating constants for unsigned
comparisons, because the point is to create an all-ones constant,
rather than UINT64_MAX, even for integers wider than 64 bits.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102946 91177308-0d34-0410-b5e6-96231b3b80d8
SimplifyICmpOperands will simplify such cases to EQ or NE. This makes
the correcntess of the code independent on SimplifyICmpOperands doing
certain simplifications.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102927 91177308-0d34-0410-b5e6-96231b3b80d8
beneficial cases. See the changes in test/CodeGen/X86/tail-opts.ll and
test/CodeGen/ARM/ifcvt2.ll for details.
The fix is to change HashEndOfMBB to hash at most one instruction,
instead of trying to apply heuristics about when it will be profitable to
consider more than one instruction. The regular tail-merging heuristics
are already prepared to handle the same cases, and they're more precise.
Also, make test/CodeGen/ARM/ifcvt5.ll and
test/CodeGen/Thumb2/thumb2-branch.ll slightly more complex so that they
continue to test what they're intended to test.
And, this eliminates the problem in
test/CodeGen/Thumb2/2009-10-15-ITBlockBranch.ll, the testcase from
PR5204. Update it accordingly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102907 91177308-0d34-0410-b5e6-96231b3b80d8
preventing the emission of the NOP on Darwin for a
function with no actual code. From timberwolfmc
with TEST=optllcdbg.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102843 91177308-0d34-0410-b5e6-96231b3b80d8
halting analysis, it is illegal to delete a call to a read-only function.
The correct solution is almost certainly to add a "must halt" attribute and
only allow deletions in its presence.
XFAIL the relevant testcase for now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102831 91177308-0d34-0410-b5e6-96231b3b80d8
if an indirect call site was removed and a direct one was added, not
just if an indirect call site was modified to be direct.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102830 91177308-0d34-0410-b5e6-96231b3b80d8
that can have a big effect :). The first is to enable the
iterative SCC passmanager juice that kicks in when the
scc passmgr detects that a function pass has devirtualized
a call. In this case, it will rerun all the passes it
manages on the SCC, up to the iteration count limit (4). This
is useful because a function pass may devirualize a call, and
we want the inliner to inline it, or pruneeh to infer stuff
about it, etc.
The second patch is to add *all* call sites to the
DevirtualizedCalls list the inliner uses. This list is
about to get renamed, but the jist of this is that the
inliner now reconsiders *all* inlined call sites as candidates
for further inlining. The intuition is this that in cases
like this:
f() { g(1); } g(int x) { h(x); }
We analyze this bottom up, and may decide that it isn't
profitable to inline H into G. Next step, we decide that it is
profitable to inline G into F, and do so, which means that F
now calls H. Even though the call from G -> H may not have been
profitable to inline, the call from F -> H may be (in this case
because a constant allows folding etc).
In my spot checks, this doesn't have a big impact on code. For
example, the LLC output for 252.eon grew from 0.02% (from
317252 to 317308) and 176.gcc actually shrunk by .3% (from 1525612
to 1520964 bytes). 252.eon never iterated in the SCC Passmgr,
176.gcc iterated at most 1 time.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102823 91177308-0d34-0410-b5e6-96231b3b80d8
that appear due to inlining a callee as candidates for
futher inlining, but a recent patch made it do this if
those call sites were indirect and became direct.
Unfortunately, in bizarre cases (see testcase) doing this
can cause us to infinitely inline mutually recursive
functions into callers not in the cycle. Fix this by
keeping track of the inline history from which callsite
inline candidates got inlined from.
This shouldn't affect any "real world" code, but is required
for a follow on patch that is coming up next.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102822 91177308-0d34-0410-b5e6-96231b3b80d8
code, and to eliminate the need for the SelectionDAGBuilder
state to be live during CodeGenAndEmitDAG calls.
Call SDB->clear() before CodeGenAndEmitDAG calls instead of
before it, and move the CurDAG->clear() out of SelectionDAGBuilder,
which doesn't own the DAG, and into CodeGenAndEmitDAG.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102814 91177308-0d34-0410-b5e6-96231b3b80d8
were still inlining self-recursive functions into other functions.
Inlining a recursive function into itself has the potential to
reduce recursion depth by a factor of 2, inlining a recursive
function into something else reduces recursion depth by exactly
1. Since inlining a recursive function into something else is a
weird form of loop peeling, turn this off.
The deleted testcase was added by Dale in r62107, since then
we're leaning towards not inlining recursive stuff ever. In any
case, if we like inlining recursive stuff, it should be done
within the recursive function itself to get the algorithm
recursion depth win.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102798 91177308-0d34-0410-b5e6-96231b3b80d8
indexes could be of a different value type. Or not even using the same SDNode
for the constant (weird, I know). Compare the actual values instead of the
pointers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102791 91177308-0d34-0410-b5e6-96231b3b80d8
instruction selection is done; it's confusing to see parts of it printed,
while other parts are omitted, along the way.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102771 91177308-0d34-0410-b5e6-96231b3b80d8
call that might throw. The landing pad assumes that all registers are in stack
slots.
We used to spill those dirty CSRs after the call, and the stack slots would be
wrong when arriving at the landing pad.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102770 91177308-0d34-0410-b5e6-96231b3b80d8
MachineFunction::DefaultDebugLoc. We now use the same technique as
DwarfDebug::beginFunction to find the starting line number for a
function.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102679 91177308-0d34-0410-b5e6-96231b3b80d8
