variable if recursing fails to simplify it.
Factor AliasedSymbol to be a method of MCSymbol.
Update MCAssembler::EvaluateFixup to match the change in
EvaluateAsRelocatableImpl.
Remove the WeakRefExpr hack, as the object writer now sees the weakref with
no extra effort needed.
Nothing else is using MCTargetExpr, but keep it for now.
Now that the ELF writer sees relocations with aliases, handle
.weak foo2
foo2:
.weak bar2
.set bar2,foo2
.quad bar2
the same way gas does and produce a relocation with bar2.
llvm-svn: 119152
This moves most of the isUsed logic to the MCSymbol itself. With this we
get a bit more relaxed about allowing definitions after uses: uses that
don't evaluate their argument immediately (jmp foo) are accepted.
ddunbar, this was the smallest compromise I could think of that lets us
accept gcc (and clang!) assembly.
llvm-svn: 119144
offload the work to hasConstantValue rather than do something more
complicated (such handling mutually recursive phis) because (1) it is
not clear it is worth it; and (2) if it is worth it, maybe such logic
would be better placed in hasConstantValue. Adjust some GVN tests
which are now cleaned up much further (eg: all phi nodes are removed).
llvm-svn: 119043
SimplifyAssociativeOrCommutative) "(A op C1) op C2" -> "A op (C1 op C2)",
which previously was only done if C1 and C2 were constants, to occur whenever
"C1 op C2" simplifies (a la InstructionSimplify). Since the simplifying operand
combination can no longer be assumed to be the right-hand terms, consider all of
the possible permutations. When compiling "gcc as one big file", transform 2
(i.e. using right-hand operands) fires about 4000 times but it has to be said
that most of the time the simplifying operands are both constants. Transforms
3, 4 and 5 each fired once. Transform 6, which is an existing transform that
I didn't change, never fired. With this change, the testcase is now optimized
perfectly with one run of instcombine (previously it required instcombine +
reassociate + instcombine, and it may just have been luck that this worked).
llvm-svn: 119002
2. Fixing several errors in disassembler uncovered by test cases.
3. Fixing invalid encoding of PCMPEQ and PCMPNE uncovered by test cases.
llvm-svn: 118969
2. Parsing .word directive in MBlaze asm parser
3. Fixing hack where memory instructions reversed order of last two parameters
4. Fixing many improperly encoded instructions
5. Support parsing special instructions (MFS,MTS,etc.)
6. Removing unused functions from inst printer
llvm-svn: 118941
support for the case where alignment<value size.
These cases were silently miscompiled before this patch.
Now they are overly verbose -especially storing is- and
any front-end should still avoid misaligned memory
accesses as much as possible. The bit juggling algorithm
added here probably has some room for improvement still.
llvm-svn: 118889
testing for dereferenceable pointers into a helper function,
isDereferenceablePointer. Teach it how to reason about GEPs
with simple non-zero indices.
Also eliminate ArgumentPromtion's IsAlwaysValidPointer,
which didn't check for weak externals or out of range gep
indices.
llvm-svn: 118840
references. For example, this allows gvn to eliminate the load in
this example:
void foo(int n, int* p, int *q) {
p[0] = 0;
p[1] = 1;
if (n) {
*q = p[0];
}
}
llvm-svn: 118714
nodes can be used in loops, this could result in infinite looping
if there is no recursion limit, so add such a limit. It is also
used for the SelectInst case because in theory there could be an
infinite loop there too if the basic block is unreachable.
llvm-svn: 118694
It is only supported for ARM code. Normally Thumb2 code would use DMB instead,
but depending on how the compiler is invoked (e.g., -mattr=-db) that might be
disabled. This prevents a "cannot select MEMBARRIER_MCR" error in that
situation. Radar 8644195
llvm-svn: 118642
to optionally look for constant or local (alloca) memory.
Teach BasicAliasAnalysis::pointsToConstantMemory to look through Select
and Phi nodes, and to support looking for local memory.
Remove FunctionAttrs' PointsToLocalOrConstantMemory function, now that
AliasAnalysis knows all the tricks that it knew.
llvm-svn: 118412
of a select instruction, see if doing the compare with the
true and false values of the select gives the same result.
If so, that can be used as the value of the comparison.
llvm-svn: 118378
different forms of this instruction (movw/movl/movq) which we reported
as being ambiguous. Since they all do the same thing, gas just picks the
one with the shortest encoding. Follow its lead here.
This implements rdar://8208615
llvm-svn: 118362
exposed:
GAS doesn't accept "fcomip %st(1)", it requires "fcomip %st(1), %st(0)"
even though st(0) is implicit in all other fp stack instructions.
Fortunately, there is an alias for fcomip named "fcompi" and gas does
accept the default argument for the alias (boggle!).
As such, switch the canonical form of this instruction to "pi" instead
of "ip". This makes the code generator and disassembler generate pi,
avoiding the gas bug.
llvm-svn: 118356
shift-by-1 instructions, where the asmstring doesn't contain
the implicit 1. It turns out that a bunch of these rotate
instructions were completely broken because they used 1
instead of $1.
This fixes assembly mismatches on "rclb $1, %bl" and friends,
where we used to generate the 3 byte form, we now generate the
proper 2-byte form.
llvm-svn: 118355
floating point stack instructions instead of looking for b/w/l/q.
This fixes issues where we'd accidentally match fistp to fistpl,
when it is in fact an ambiguous instruction.
This changes the behavior of llvm-mc to reject fstp, which was the
correct fix for rdar://8456389:
t.s:1:1: error: ambiguous instructions require an explicit suffix (could be 'fstps', 'fstpl', or 'fstpt')
fstp (%rax)
it also causes us to correctly reject fistp and fist, which addresses
PR8528:
t.s:2:1: error: ambiguous instructions require an explicit suffix (could be 'fistps', or 'fistpl')
fistp (%rax)
^
t.s:3:1: error: ambiguous instructions require an explicit suffix (could be 'fists', or 'fistl')
fist (%rax)
^
Thanks to Ismail Donmez for tracking down the issue here!
llvm-svn: 118346
sequence of loads and stores was being generated to perform the
copy on the x86 targets if the parameter was less than 4 byte
aligned, causing llc to use up vast amounts of memory and time.
Use a "rep movs" form instead. PR7170.
llvm-svn: 118260
all of the different element sizes are pseudo instructions that map down to vext.8 underneath, with
the immediate shifted left to reflect the increased element size.
llvm-svn: 118183
vldr.64 d1, [r0, #-32]
The problem was with how the addressing mode 5 encodes the offsets. This change
makes sure that the way offsets are handled in addressing mode 5 is consistent
throughout the MC code. It involves re-refactoring the "getAddrModeImmOpValue"
method into an "Imm12" and "addressing mode 5" version. But not to worry! The
majority of the duplicated code has been unified.
llvm-svn: 118144
1. Fix pre-ra scheduler so it doesn't try to push instructions above calls to
"optimize for latency". Call instructions don't have the right latency and
this is more likely to use introduce spills.
2. Fix if-converter cost function. For ARM, it should use instruction latencies,
not # of micro-ops since multi-latency instructions is completely executed
even when the predicate is false. Also, some instruction will be "slower"
when they are predicated due to the register def becoming implicit input.
rdar://8598427
llvm-svn: 118135
with immediates up to 16-bits in size. The same logic is applied to other LDR
encodings, e.g. VLDR, but which use a different immediate bit width (8-bits in
VLDR's case). Removing the "12" allows it to be more generic.
llvm-svn: 118094
at more than those which define CPSR. You can have this situation:
(1) subs ...
(2) sub r6, r5, r4
(3) movge ...
(4) cmp r6, 0
(5) movge ...
We cannot convert (2) to "subs" because (3) is using the CPSR set by
(1). There's an analogous situation here:
(1) sub r1, r2, r3
(2) sub r4, r5, r6
(3) cmp r4, ...
(5) movge ...
(6) cmp r1, ...
(7) movge ...
We cannot convert (1) to "subs" because of the intervening use of CPSR.
llvm-svn: 117950
aliases installed and working. They now work when the
matched pattern and the result instruction have exactly
the same operand list.
This is now enough for us to define proper aliases for
movzx and movsx, implementing rdar://8017633 and PR7459.
Note that we do not accept instructions like:
movzx 0(%rsp), %rsi
GAS accepts this instruction, but it doesn't make any
sense because we don't know the size of the memory
operand. It could be 8/16/32 bits.
llvm-svn: 117901
in their asmstring. Fix the two x86 "NOREX" instructions that have them.
If these comments are important, the instlowering stuff can print them.
llvm-svn: 117897
consider it to be readonly. In fact, don't even consider it to be
readonly if it does a volatile load from an AllocaInst either (it
is debatable as to whether readonly would be correct or not in this
case; play safe for the moment). This fixes PR8279.
llvm-svn: 117783
There were a number of issues to fix up here:
* The "device" argument of the llvm.memory.barrier intrinsic should be
used to distinguish the "Full System" domain from the "Inner Shareable"
domain. It has nothing to do with using DMB vs. DSB instructions.
* The compiler should never need to emit DSB instructions. Remove the
ARMISD::SYNCBARRIER node and also remove the instruction patterns for DSB.
* Merge the separate DMB/DSB instructions for options only used for the
disassembler with the default DMB/DSB instructions. Add the default
"full system" option ARM_MB::SY to the ARM_MB::MemBOpt enum.
* Add a separate ARMISD::MEMBARRIER_MCR node for subtargets that implement
a data memory barrier using the MCR instruction.
* Fix up encodings for these instructions (except MCR).
I also updated the tests and added a few new ones to check for DMB options
that were not currently being exercised.
llvm-svn: 117756
Duncan Sands