uint32_t hi(uint64_t res)
{
uint_32t hi = res >> 32;
return !hi;
}
llvm IR looks like this:
define i32 @hi(i64 %res) nounwind uwtable ssp {
entry:
%lnot = icmp ult i64 %res, 4294967296
%lnot.ext = zext i1 %lnot to i32
ret i32 %lnot.ext
}
The optimizer has optimize away the right shift and truncate but the resulting
constant is too large to fit in the 32-bit immediate field. The resulting x86
code is worse as a result:
movabsq $4294967296, %rax ## imm = 0x100000000
cmpq %rax, %rdi
sbbl %eax, %eax
andl $1, %eax
This patch teaches the x86 lowering code to handle ult against a large immediate
with trailing zeros. It will issue a right shift and a truncate followed by
a comparison against a shifted immediate.
shrq $32, %rdi
testl %edi, %edi
sete %al
movzbl %al, %eax
It also handles a ugt comparison against a large immediate with trailing bits
set. i.e. X > 0x0ffffffff -> (X >> 32) >= 1
rdar://11866926
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160312 91177308-0d34-0410-b5e6-96231b3b80d8
The first variant accepts immediate number as the second argument.
The second variant accepts register operand as the second argument.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160307 91177308-0d34-0410-b5e6-96231b3b80d8
In the added testcase the constant 55 was behind an AssertZext of type i1, and ComputeDemandedBits
reported that some of the bits were both known to be one and known to be zero.
Together with Michael Kuperstein <michael.m.kuperstein@intel.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160305 91177308-0d34-0410-b5e6-96231b3b80d8
Make it always return APInts with the same bitwidth for the same ConstantRange bitwidth to simply clients
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160294 91177308-0d34-0410-b5e6-96231b3b80d8
Mips shift instructions DSLL, DSRL and DSRA are transformed into
DSLL32, DSRL32 and DSRA32 respectively if the shift amount is between
32 and 63
Here is a description of DSLL:
Purpose: Doubleword Shift Left Logical Plus 32
To execute a left-shift of a doubleword by a fixed amount--32 to 63 bits
Description: GPR[rd] <- GPR[rt] << (sa+32)
The 64-bit doubleword contents of GPR rt are shifted left, inserting
zeros into the emptied bits; the result is placed in
GPR rd. The bit-shift amount in the range 0 to 31 is specified by sa.
This patch implements the direct object output of these instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160277 91177308-0d34-0410-b5e6-96231b3b80d8
1. FileCheck-ize epilogue.ll and allow another asm instruction to restore %rsp.
2. Remove check in widen_arith-3.ll that was hitting instruction in epilogue instead of
vector add.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160274 91177308-0d34-0410-b5e6-96231b3b80d8
undef virtual register. The problem is that ProcessImplicitDefs removes the
definition of the register and marks all uses as undef. If we lose the undef
marker then we get a register which has no def, is not marked as undef. The
live interval analysis does not collect information for these virtual
registers and we crash in later passes.
Together with Michael Kuperstein <michael.m.kuperstein@intel.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160260 91177308-0d34-0410-b5e6-96231b3b80d8
It turns out that ASan relied on the at-the-end block insertion order to
(purely by happenstance) disable some LLVM optimizations, which in turn
start firing when the ordering is made more "normal". These
optimizations in turn merge many of the instrumentation reporting calls
which breaks the return address based error reporting in ASan.
We're looking at several different options for fixing this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160256 91177308-0d34-0410-b5e6-96231b3b80d8
This is particularly useful to the backend code generators which try to
process things in the incoming function order.
Also, cleanup some uses of IRBuilder to be a bit simpler and more clear.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160254 91177308-0d34-0410-b5e6-96231b3b80d8
functionality test.
In general, unless the functionality is substantially separated, we
should lump more basic testing into this file. The test running
infrastructure likes having a few test files with more comprehensive
testing within them.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160253 91177308-0d34-0410-b5e6-96231b3b80d8
Added a basic unit test for this with CreateCondBr. I didn't go all the
way and test the switch side as the boilerplate for setting up the
switch IRBuilder unit tests is a lot more. Fortunately, the two share
all the interesting code paths.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160251 91177308-0d34-0410-b5e6-96231b3b80d8
It is intended to fix PR11468.
Old prologue and epilogue looked like this:
push %rbp
mov %rsp, %rbp
and $alignment, %rsp
push %r14
push %r15
...
pop %r15
pop %r14
mov %rbp, %rsp
pop %rbp
The problem was to reference the locations of callee-saved registers in exception handling:
locations of callee-saved had to be re-calculated regarding the stack alignment operation. It would
take some effort to implement this in LLVM, as currently MachineLocation can only have the form
"Register + Offset". Funciton prologue and epilogue are now changed to:
push %rbp
mov %rsp, %rbp
push %14
push %15
and $alignment, %rsp
...
lea -$size_of_saved_registers(%rbp), %rsp
pop %r15
pop %r14
pop %rbp
Reviewed by Chad Rosier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160248 91177308-0d34-0410-b5e6-96231b3b80d8
the move of *Builder classes into the Core library.
No uses of this builder in Clang or DragonEgg I could find.
If there is a desire to have an IR-building-support library that
contains all of these builders, that can be easily added, but currently
it seems likely that these add no real overhead to VMCore.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160243 91177308-0d34-0410-b5e6-96231b3b80d8
IRBuilder, DIBuilder, etc.
This is the proper layering as MDBuilder can't be used (or implemented)
without the Core Metadata representation.
Patches to Clang and Dragonegg coming up.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160237 91177308-0d34-0410-b5e6-96231b3b80d8
Allow the folding of vbroadcastRR to vbroadcastRM, where the memory operand is a spill slot.
PR12782.
Together with Michael Kuperstein <michael.m.kuperstein@intel.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160230 91177308-0d34-0410-b5e6-96231b3b80d8
Add a micro-optimization to getNode of CONCAT_VECTORS when both operands are undefs.
Can't find a testcase for this because VECTOR_SHUFFLE already handles undef operands, but Duncan suggested that we add this.
Together with Michael Kuperstein <michael.m.kuperstein@intel.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160229 91177308-0d34-0410-b5e6-96231b3b80d8
The notable fix is to look at any dependencies attached to the kill
instruction (or other instructions between MI nad the kill) where the
dependencies are specific to the register in question.
The old code implicitly handled this by rejecting the transform if *any*
other uses were found within the block, but after the start point. The
new code directly finds the kill, and has to re-use the existing
dependency scan to check for non-kill uses.
This was caught by self-host, but I found the bug via inspection and use
of absurd assert scaffolding to compute the kills in two ways and
compare them. So I have no useful testcase for this other than
"bootstrap". I'd work harder to reduce a test case if this particular
code were likely to live for a long time.
Thanks to Benjamin Kramer for reviewing the fix itself.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160228 91177308-0d34-0410-b5e6-96231b3b80d8