- Fix a typo for PIC check during jmp table lowering
- Also fix the "first jump table basic block is not
considered only reachable by fall through" problem, use this
ad-hoc solution until I come up with something better.
Patch by stetorvs@gmail.com
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108820 91177308-0d34-0410-b5e6-96231b3b80d8
update the current basic block in addition to the current insert
position, so that they remain consistent. This fixes rdar://8204072.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108765 91177308-0d34-0410-b5e6-96231b3b80d8
instruction, we only want to allow the one for the current subtarget.
- This also fixes suffix matching for jmp instructions, because it eliminates
the ambiguity between 'jmpl' and 'jmpq'.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108746 91177308-0d34-0410-b5e6-96231b3b80d8
instruction for non-constant operands. This includes the case referenced
in the README.txt regarding a bitfield copy.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108608 91177308-0d34-0410-b5e6-96231b3b80d8
and a combine pattern to use it for setting a bit-field to a constant
value. More to come for non-constant stores.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108570 91177308-0d34-0410-b5e6-96231b3b80d8
void foo() { __builtin_unreachable(); }
It will output the following on Darwin X86:
_func1:
Leh_func_begin0:
pushq %rbp
Ltmp0:
movq %rsp, %rbp
Ltmp1:
Leh_func_end0:
This prolog adds a new Call Frame Information (CFI) row to the FDE with an
address that is not within the address range of the code it describes -- part is
equal to the end of the function -- and therefore results in an invalid EH
frame. If we emit a nop in this situation, then the CFI row is now within the
address range.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108568 91177308-0d34-0410-b5e6-96231b3b80d8
pass that inserted it.
It is no longer necessary to limit the live ranges of FP registers to a single
basic block.
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occasions, caused code to be generated in a different order.
All cases I've seen involved float softening in the type
legalizer, and this could be perhaps be fixed there, but
it's better not to generate things differently in the first
place. 7797940 (6/29/2010..7/15/2010).
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it doesn't miss an opportunity to form a GEP, regardless of the
relative loop depths of the operands. This fixes rdar://8197217.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108475 91177308-0d34-0410-b5e6-96231b3b80d8
the function. We'll just turn it into a "trap" instruction instead.
The problem with not handling this is that it might generate a prologue without
the equivalent epilogue to go with it:
$ cat t.ll
define void @foo() {
entry:
unreachable
}
$ llc -o - t.ll -relocation-model=pic -disable-fp-elim -unwind-tables
.section __TEXT,__text,regular,pure_instructions
.globl _foo
.align 4, 0x90
_foo: ## @foo
Leh_func_begin0:
## BB#0: ## %entry
pushq %rbp
Ltmp0:
movq %rsp, %rbp
Ltmp1:
Leh_func_end0:
...
The unwind tables then have bad data in them causing all sorts of problems.
Fixes <rdar://problem/8096481>.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108473 91177308-0d34-0410-b5e6-96231b3b80d8
-enable-no-nans-fp-math and -enable-no-infs-fp-math. All of the current codegen fp math optimizations only care whether the fp arithmetics arguments and results can never be NaN.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108465 91177308-0d34-0410-b5e6-96231b3b80d8
to keep "Text" in sync with the "pure instructions" section attribute.
Lack of this attribute was preventing the assembler from emitting
multibyte noops instructions for templates (and inlines, and other
coalesced stuff) and was causing the assembler to mismatch .o files.
This fixes rdar://8018335
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a zero. This situation arrises in Fortran code with induction variables
that start at 1 instead of 0. This fixes PR7651.
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mutated by recursive simplification. This also enhances
ReplaceAndSimplifyAllUses to actually do a real RAUW
at the end of it, which updates any value handles
pointing to "From" to start pointing to "To". This
seems useful for debug info and random other VH users.
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in the literal field of an instruction. E.g.,
long long foo(long long a) {
return a - 734439407618LL;
}
rdar://7038284
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address cannot be allocated a register is in 32-bit mode where the first
three arguments are marked inreg. In that case EAX, EDX, and ECX will be
used for argument passing.
This fixes PR7610.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108327 91177308-0d34-0410-b5e6-96231b3b80d8
by a return that returns a constant, while elsewhere in the function
another return instruction returns a different constant. This is a
special case of accumulator recursion, so just generalize the existing
logic a bit.
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the LHS and RHS of an and/or instruction, don't multiply add
known predecessor values. This fixes the crash on testcase
from PR7498
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Targets must now implement TargetInstrInfo::copyPhysReg instead. There is no
longer a default implementation forwarding to copyRegToReg.
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correct alignment information, which simplifies ExpandRes_VAARG a bit.
The patch introduces a new alignment information to TargetLoweringInfo. This is
needed since the two natural candidates cannot be used:
* The 's' in target data: If this is set to the minimal alignment of any
argument, getCallFrameTypeAlignment would return 4 for doubles on ARM for
example.
* The getTransientStackAlignment method. It is possible for an architecture to
have argument less aligned than what we maintain the stack pointer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108072 91177308-0d34-0410-b5e6-96231b3b80d8
- Check getBytesToPopOnReturn().
- Eschew ST0 and ST1 for return values.
- Fix the PIC base register initialization so that it doesn't ever
fail to end up the top of the entry block.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108039 91177308-0d34-0410-b5e6-96231b3b80d8
notes:
- The instructions are being added with dummy placeholder patterns using some 256
specifiers, this is not meant to work now, but since there are some multiclasses
generic enough to accept them, when we go for codegen, the stuff will be already
there.
- Add VEX encoding bits to support YMM
- Add MOVUPS and MOVAPS in the first round
- Use "Y" as suffix for those Instructions: MOVUPSYrr, ...
- All AVX instructions in X86InstrSSE.td will move soon to a new X86InstrAVX
file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107996 91177308-0d34-0410-b5e6-96231b3b80d8
U utils/TableGen/FastISelEmitter.cpp
--- Reverse-merging r107943 into '.':
U test/CodeGen/X86/fast-isel.ll
U test/CodeGen/X86/fast-isel-loads.ll
U include/llvm/Target/TargetLowering.h
U include/llvm/Support/PassNameParser.h
U include/llvm/CodeGen/FunctionLoweringInfo.h
U include/llvm/CodeGen/CallingConvLower.h
U include/llvm/CodeGen/FastISel.h
U include/llvm/CodeGen/SelectionDAGISel.h
U lib/CodeGen/LLVMTargetMachine.cpp
U lib/CodeGen/CallingConvLower.cpp
U lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
U lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
U lib/CodeGen/SelectionDAG/FastISel.cpp
U lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
U lib/CodeGen/SelectionDAG/ScheduleDAGSDNodes.cpp
U lib/CodeGen/SelectionDAG/InstrEmitter.cpp
U lib/CodeGen/SelectionDAG/TargetLowering.cpp
U lib/Target/XCore/XCoreISelLowering.cpp
U lib/Target/XCore/XCoreISelLowering.h
U lib/Target/X86/X86ISelLowering.cpp
U lib/Target/X86/X86FastISel.cpp
U lib/Target/X86/X86ISelLowering.h
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disabled and then never turned back on again. Adjust some tests, one because
this change avoids an unnecessary instruction, and the other to make it
continue testing what it was intended to test.
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in memory operands at the same type as hard coded segments.
This fixes problems where we'd emit the segment override after
the REX prefix on instructions like:
mov %gs:(%rdi), %rax
This fixes rdar://8127102. I have several cleanup patches coming
next.
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(X >s -1) ? C1 : C2 and (X <s 0) ? C2 : C1
into ((X >>s 31) & (C2 - C1)) + C1, avoiding the conditional.
This optimization could be extended to take non-const C1 and C2 but we better
stay conservative to avoid code size bloat for now.
for
int sel(int n) {
return n >= 0 ? 60 : 100;
}
we now generate
sarl $31, %edi
andl $40, %edi
leal 60(%rdi), %eax
instead of
testl %edi, %edi
movl $60, %ecx
movl $100, %eax
cmovnsl %ecx, %eax
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1. The arguments are f32.
2. The arguments are loads and they have no uses other than the comparison.
3. The comparison code is EQ or NE.
e.g.
vldr.32 s0, [r1]
vldr.32 s1, [r0]
vcmpe.f32 s1, s0
vmrs apsr_nzcv, fpscr
beq LBB0_2
=>
ldr r1, [r1]
ldr r0, [r0]
cmp r0, r1
beq LBB0_2
More complicated cases will be implemented in subsequent patches.
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Add explicit testcases for tail calls within the same module.
Duplicate some code to humor those who think .w doesn't apply on ARM.
Leave this disabled on Thumb1, and add some comments explaining why it's hard
and won't gain much.
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interface needs implementations to be consistent, so any code which
wants to support different semantics must use a different interface.
It's not currently worthwhile to add a new interface for this new
concept.
Document that AliasAnalysis doesn't support cross-function queries.
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It is OK for an alias live range to overlap if there is a copy to or from the
physical register. CoalescerPair can work out if the copy is coalescable
independently of the alias.
This means that we can join with the actual destination interval instead of
using the getOrigDstReg() hack. It is no longer necessary to merge clobber
ranges into subregisters.
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the example in the testcase, we now generate:
_test1: ## @test1
movss 4(%esp), %xmm0
addss 8(%esp), %xmm0
movl 12(%esp), %eax
movss %xmm0, (%eax)
ret
instead of:
_test1: ## @test1
subl $20, %esp
movl 24(%esp), %eax
movq %mm0, (%esp)
movq %mm0, 8(%esp)
movss (%esp), %xmm0
addss 12(%esp), %xmm0
movss %xmm0, (%eax)
addl $20, %esp
ret
v2f32 support did not work reliably because most of the X86
backend didn't know it was legal. It was apparently only added
to support returning source-level v2f32 values in MMX registers
in x86-32 mode. If ABI compatibility is important on this
GCC-extended-vector type for some reason, then the frontend
should generate IR that returns v2i32 instead of v2f32. However,
we generally don't try very hard to be abi compatible on gcc
extended vectors.
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v2f32 as legal in 32-bit mode. It is just as terrible there,
but I just care about x86-64 and noone claims it is valuable
in 64-bit mode.
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- Fix VEX prefix to be emitted with 3 bytes whenever VEX_5M
represents a REX equivalent two byte leading opcode
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107523 91177308-0d34-0410-b5e6-96231b3b80d8
- X86 unfolding should check if the instructions being unfolded has memoperands.
If there is no memoperands, then it must assume conservative alignment. If this
would introduce an expensive sse unaligned load / store, then unfoldMemoryOperand
etc. should not unfold the instruction.
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PrologEpilog code, and use it to determine whether
the asm forces stack alignment or not. gcc consistently
does not do this for GCC-style asms; Apple gcc inconsistently
sometimes does it for asm blocks. There is no
convenient place to put a bit in either the SDNode or
the MachineInstr form, so I've added an extra operand
to each; unlovely, but it does allow for expansion for
more bits, should we need it. PR 5125. Some
existing testcases are affected.
The operand lists of the SDNode and MachineInstr forms
are indexed with awesome mnemonics, like "2"; I may
fix this someday, but not now. I'm not making it any
worse. If anyone is inspired I think you can find all
the right places from this patch.
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getFunctionAlignment and the corresponding use of that value in the ARM
asm printer, but now we're using the standard asm printer. The result of
this was that function alignments were dropped completely for Thumb functions.
Radar 8143571.
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Objective-C metadata types which should be marked as "weak", but which the
linker will remove upon final linkage. However, this linkage isn't specific to
Objective-C.
For example, the "objc_msgSend_fixup_alloc" symbol is defined like this:
.globl l_objc_msgSend_fixup_alloc
.weak_definition l_objc_msgSend_fixup_alloc
.section __DATA, __objc_msgrefs, coalesced
.align 3
l_objc_msgSend_fixup_alloc:
.quad _objc_msgSend_fixup
.quad L_OBJC_METH_VAR_NAME_1
This is different from the "linker_private" linkage type, because it can't have
the metadata defined with ".weak_definition".
Currently only supported on Darwin platforms.
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such a way that debug info for symbols preserved even if symbols are
optimized away by the optimizer.
Add new special pass to remove debug info for such symbols.
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available in a register. This is pretty primitive, but it reduces the
number of instructions in common testcases by 4%.
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- Add encode bits for VEX_W
- All 128-bit SSE 1 & SSE2 instructions that are described
in the .td file now have a AVX encoded form already working.
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A partial redefine needs to be treated like a tied operand, and the register
must be reloaded while processing use operands.
This fixes a bug where partially redefined registers were processed as normal
defs with a reload added. The reload could clobber another use operand if it was
a kill that allowed register reuse.
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The LowerSubregs pass needs to preserve implicit def operands attached to
EXTRACT_SUBREG instructions when it replaces those instructions with copies.
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of getPhysicalRegisterRegClass with it.
If we want to make a copy (or estimate its cost), it is better to use the
smallest class as more efficient operations might be possible.
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There are 2 changes relative to the previous version of the patch:
1) For the "simple" if-conversion case, there's no need to worry about
RemoveExtraEdges not handling an unanalyzable branch. Predicated terminators
are ignored in this context, so RemoveExtraEdges does the right thing.
This might break someday if we ever treat indirect branches (BRIND) as
predicable, but for now, I just removed this part of the patch, because
in the case where we do not add an unconditional branch, we rely on keeping
the fall-through edge to CvtBBI (which is empty after this transformation).
The change relative to the previous patch is:
@@ -1036,10 +1036,6 @@
IterIfcvt = false;
}
- // RemoveExtraEdges won't work if the block has an unanalyzable branch,
- // which is typically the case for IfConvertSimple, so explicitly remove
- // CvtBBI as a successor.
- BBI.BB->removeSuccessor(CvtBBI->BB);
RemoveExtraEdges(BBI);
// Update block info. BB can be iteratively if-converted.
2) My patch exposed a bug in the code for merging the tail of a "diamond",
which had previously never been exercised. The code was simply checking that
the tail had a single predecessor, but there was a case in
MultiSource/Benchmarks/VersaBench/dbms where that single predecessor was
neither edge of the diamond. I added the following change to check for
that:
@@ -1276,7 +1276,18 @@
// tail, add a unconditional branch to it.
if (TailBB) {
BBInfo TailBBI = BBAnalysis[TailBB->getNumber()];
- if (TailBB->pred_size() == 1 && !TailBBI.HasFallThrough) {
+ bool CanMergeTail = !TailBBI.HasFallThrough;
+ // There may still be a fall-through edge from BBI1 or BBI2 to TailBB;
+ // check if there are any other predecessors besides those.
+ unsigned NumPreds = TailBB->pred_size();
+ if (NumPreds > 1)
+ CanMergeTail = false;
+ else if (NumPreds == 1 && CanMergeTail) {
+ MachineBasicBlock::pred_iterator PI = TailBB->pred_begin();
+ if (*PI != BBI1->BB && *PI != BBI2->BB)
+ CanMergeTail = false;
+ }
+ if (CanMergeTail) {
MergeBlocks(BBI, TailBBI);
TailBBI.IsDone = true;
} else {
With these fixes, I was able to run all the SingleSource and MultiSource
tests successfully.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107110 91177308-0d34-0410-b5e6-96231b3b80d8
properly handles instructions and arguments defined in different
functions, or across recursive function iterations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107109 91177308-0d34-0410-b5e6-96231b3b80d8
have to be registers, per gcc documentation. This affects
the logic for determining what "g" should lower to. PR 7393.
A couple of existing testcases are affected.
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When an instruction has tied operands and physreg defines, we must take extra
care that the tied operands conflict with neither physreg defs nor uses.
The special treatment is given to inline asm and instructions with tied operands
/ early clobbers and physreg defines.
This fixes PR7509.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107043 91177308-0d34-0410-b5e6-96231b3b80d8
regressions.
--- Reverse-merging r106939 into '.':
U test/CodeGen/Thumb2/thumb2-ifcvt3.ll
U lib/CodeGen/IfConversion.cpp
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106951 91177308-0d34-0410-b5e6-96231b3b80d8
the returned value after the tail call if it differs from other return
values. The optimal thing to do would be to introduce a phi node for
the return value, but for the moment just fix the miscompile.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106947 91177308-0d34-0410-b5e6-96231b3b80d8
if-conversion. The RemoveExtraEdges function doesn't work for blocks that
end with unanalyzable branches, so in those cases, the "extra" edges must
be explicitly removed. The CopyAndPredicateBlock and MergeBlocks methods
can also avoid copying successor edges due to branches that have already
been removed. The latter case is especially helpful when MergeBlocks is
called for handling "diamond" if-conversions, where otherwise you can end
up with some weird intermediate states in the CFG. Unfortunately I've
been unable to find cases where this cleanup actually makes a significant
difference in the code. There is one test where we manage to remove an
empty block at the end of a function. Radar 6911268.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106939 91177308-0d34-0410-b5e6-96231b3b80d8
CopyFromReg nodes for aliasing registers (AX and AL). This confuses the fast
register allocator.
Instead of CopyFromReg(AL), use ExtractSubReg(CopyFromReg(AX), sub_8bit).
This fixes PR7312.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106934 91177308-0d34-0410-b5e6-96231b3b80d8
introduced in r106343, but only showed up recently (with a particular compiler &
linker combination) because of the particular check, and because we have no
builtin checking for dereferencing the end of an array, which is truly
unfortunate.
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for an "i" constraint should get lowered; PR 6309. While
this argument was passed around a lot, this is the only
place it was used, so it goes away from a lot of other
places.
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original SDNode. This is badness. Also, this function allows one SDNode to point
multiple flags to another SDNode. Badness as well.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106793 91177308-0d34-0410-b5e6-96231b3b80d8
address requires a register or secondary load to compute
(most PIC modes). This improves "g" constraint handling. 8015842.
The test from 2007 is attempting to test the fix for PR1761,
but since -relocation-model=static doesn't work on Darwin
x86-64, it was not testing what it was supposed to be testing
and was passing erroneously. Fixed to use Linux x86-64.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106779 91177308-0d34-0410-b5e6-96231b3b80d8
CoalescerPair can determine if a copy can be coalesced, and which register gets
merged away. The old logic in SimpleRegisterCoalescing had evolved into
something a bit too convoluted.
This second attempt fixes some crashes that only occurred Linux.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106769 91177308-0d34-0410-b5e6-96231b3b80d8
when the condition is constant. This optimization shouldn't be
necessary, because codegen shouldn't be able to find dead control
paths that the IR-level optimizer can't find. And it's undesirable,
because it encourages bugpoint to leave "br i1 false" branches
in its output. And it wasn't updating the CFG.
I updated all the tests I could, but some tests are too reduced
and I wasn't able to meaningfully preserve them.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106748 91177308-0d34-0410-b5e6-96231b3b80d8
