which is simpler than finding a place to insert in BB.
- Don't perform the 'if condition hoisting' xform on certain
i1 PHIs, as it interferes with switch formation.
This re-fixes "example 7", without breaking the world hopefully.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121764 91177308-0d34-0410-b5e6-96231b3b80d8
first, it can kick in on blocks whose conditions have been
folded to a constant, even though one of the edges will be
trivially folded.
second, it doesn't clean up the "if diamond" that it just
eliminated away. This is a problem because other simplifycfg
xforms kick in depending on the order of block visitation,
causing pointless work.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121762 91177308-0d34-0410-b5e6-96231b3b80d8
instruction based on the t_addrmode_s# mode and what it returned. There is some
obvious badness to this. In particular, it's hard to do MC-encoding when the
instruction may change out from underneath you after the t_addrmode_s# variable
is finally resolved.
The solution is to revert a long-ago change that merged the reg/reg and reg/imm
versions. There is the addition of several new addressing modes. They no longer
have extraneous operands associated with them. I.e., if it's reg/reg we don't
have to have a dummy zero immediate tacked on to the SDNode.
There are some obvious cleanups here, which will happen shortly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121747 91177308-0d34-0410-b5e6-96231b3b80d8
spill weight. Filter out fixed registers instead.
Add support for reassigning an interference that was assigned to an alias.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121737 91177308-0d34-0410-b5e6-96231b3b80d8
Use the same COPY_TO_REGCLASS approach as for the 2-register *_sfp instructions.
This change made a big difference in the code generated for the
CodeGen/Thumb2/cross-rc-coalescing-2.ll test: The coalescer is still doing
a fine job, but some instructions that were previously moved outside the loop
are not moved now. It's using fewer VFP registers now, which is generally
a good thing, so I think the estimates for register pressure changed and that
affected the LICM behavior. Since that isn't obviously wrong, I've just
changed the test file. This completes the work for Radar 8711675.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121730 91177308-0d34-0410-b5e6-96231b3b80d8
Jakob Olesen suggested that we can avoid the need for separate pseudo
instructions here by using COPY_TO_REGCLASS in the patterns. The pattern
gets pretty ugly but it seems to work well. Partial fix for Radar 8711675.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121718 91177308-0d34-0410-b5e6-96231b3b80d8
as a "long" direct branch. While the mnemonics are the same, they encode the branch offset differently, and
the Darwin assembler appears to prefer the "long" form for direct branches. Thus, in the name of bitwise
equivalence, provide encoding and fixup support for it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121710 91177308-0d34-0410-b5e6-96231b3b80d8
when the wider type is legal. This allows us to compile:
define zeroext i16 @test1(i16 zeroext %x) nounwind {
entry:
%div = udiv i16 %x, 33
ret i16 %div
}
into:
test1: # @test1
movzwl 4(%esp), %eax
imull $63551, %eax, %eax # imm = 0xF83F
shrl $21, %eax
ret
instead of:
test1: # @test1
movw $-1985, %ax # imm = 0xFFFFFFFFFFFFF83F
mulw 4(%esp)
andl $65504, %edx # imm = 0xFFE0
movl %edx, %eax
shrl $5, %eax
ret
Implementing rdar://8760399 and example #4 from:
http://blog.regehr.org/archives/320
We should implement the same thing for [su]mul_hilo, but I don't
have immediate plans to do this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121696 91177308-0d34-0410-b5e6-96231b3b80d8
for each constant pool entry. Using WriteTypeSymbolic here takes time
proportional to the size of the module, for each constant pool entry.
This speeds up -verbose-asm llc on 252.eon (a random testcase at my disposal)
from 4.4s to 2.137s. llc takes 2.11s with asm-verbose off, so this is now a
pretty reasonable cost for verbose comments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121691 91177308-0d34-0410-b5e6-96231b3b80d8
when simplifying, allowing them to be eagerly turned into switches. This
is the last step required to get "Example 7" from this blog post:
http://blog.regehr.org/archives/320
On X86, we now generate this machine code, which (to my eye) seems better
than the ICC generated code:
_crud: ## @crud
## BB#0: ## %entry
cmpb $33, %dil
jb LBB0_4
## BB#1: ## %switch.early.test
addb $-34, %dil
cmpb $58, %dil
ja LBB0_3
## BB#2: ## %switch.early.test
movzbl %dil, %eax
movabsq $288230376537592865, %rcx ## imm = 0x400000017001421
btq %rax, %rcx
jb LBB0_4
LBB0_3: ## %lor.rhs
xorl %eax, %eax
ret
LBB0_4: ## %lor.end
movl $1, %eax
ret
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121690 91177308-0d34-0410-b5e6-96231b3b80d8
