This makes the extra copyRegToReg calls in ScheduleDAGSDNodesEmit.cpp
unnecessary. Derived from a patch by Jakob Stoklund Olesen.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69635 91177308-0d34-0410-b5e6-96231b3b80d8
clang: error: unable to make temporary file: /etc/cc: can't make
unique filename: Permission denied
instead of
clang: error: unable to make temporary file: /etc/cc: can't make
unique filenamePermission denied
for example.
Also, audited the uses of MakeErrMsg to make the prefix strings
consistent (not end with newline/punctuation/space/": ").
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in the MachineFunction class, renaming it to addLiveIn for consistency with
the same method in MachineBasicBlock. Thanks for Anton for suggesting this.
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%reg1498<def> = MOV32rm %reg1024, 1, %reg0, 12, %reg0, Mem:LD(4,4) [sunkaddr39 + 0]
%reg1506<def> = MOV32rm %reg1024, 1, %reg0, 8, %reg0, Mem:LD(4,4) [sunkaddr42 + 0]
%reg1486<def> = MOV32rr %reg1506
%reg1486<def> = XOR32rr %reg1486, %reg1498, %EFLAGS<imp-def,dead>
%reg1510<def> = MOV32rm %reg1024, 1, %reg0, 4, %reg0, Mem:LD(4,4) [sunkaddr45 + 0]
=>
%reg1498<def> = MOV32rm %reg2036, 1, %reg0, 12, %reg0, Mem:LD(4,4) [sunkaddr39 + 0]
%reg1506<def> = MOV32rm %reg2037, 1, %reg0, 8, %reg0, Mem:LD(4,4) [sunkaddr42 + 0]
%reg1486<def> = MOV32rr %reg1506
%reg1486<def> = XOR32rr %reg1486, %reg1498, %EFLAGS<imp-def,dead>
%reg1510<def> = MOV32rm %reg2038, 1, %reg0, 4, %reg0, Mem:LD(4,4) [sunkaddr45 + 0]
From linearscan's point of view, each of reg2036, 2037, and 2038 are separate registers, each is "killed" after a single use. The reloaded register is available and it's often clobbered right away. e.g. In thise case reg1498 is allocated EAX while reg2036 is allocated RAX. This means we end up with multiple reloads from the same stack slot in the same basic block.
Now linearscan recognize there are other reloads from same SS in the same BB. So it'll "downgrade" RAX (and its aliases) after reg2036 is allocated until the next reload (reg2037) is done. This greatly increase the likihood reloads from SS are reused.
This speeds up sha1 from OpenSSL by 5.8%. It is also an across the board win for SPEC2000 and 2006.
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bigger than the vector element type, turn checking
of the operand type back on again, appropriately
adjusted.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69516 91177308-0d34-0410-b5e6-96231b3b80d8
type as the vector element type: allow them to be of
a wider integer type than the element type all the way
through the system, and not just as far as LegalizeDAG.
This should be safe because it used to be this way
(the old type legalizer would produce such nodes), so
backends should be able to handle it. In fact only
targets which have legal vector types with an illegal
promoted element type will ever see this (eg: <4 x i16>
on ppc). This fixes a regression with the new type
legalizer (vec_splat.ll). Also, treat SCALAR_TO_VECTOR
the same as BUILD_VECTOR. After all, it is just a
special case of BUILD_VECTOR.
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leaq foo@TLSGD(%rip), %rdi
as part of the instruction sequence. Using a register other than %rdi and then
copying it to %rdi is not valid.
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register is available and when it's profitable.
e.g.
xorq %r12<kill>, %r13
addq %rax, -184(%rbp)
addq %r13, -184(%rbp)
==>
xorq %r12<kill>, %r13
movq -184(%rbp), %r12
addq %rax, %r12
addq %r13, %r12
movq %r12, -184(%rbp)
Two more instructions, but fewer memory accesses. It can also open up
opportunities for more optimizations.
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this fixes a crash on CodeGen/Generic/externally_available.ll
on ppc hosts. Thanks to Nicholas L for pointing this out.
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locks must be matched with unlocks. Also, use calloc to allocate the
block so that it is properly zero'd. Thanks to Nick Kledzik for
tracking this down.
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add dependencies on nodes with exactly one successor which is a
COPY_TO_REGCLASS node. In the case that the copy is coalesced
away, the dependence should be on the user of the copy, rather
than the copy itself.
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size from the integer, requiring zero extension or truncation. Don't
create ZExtInsts with pointer types. This fixes a regression in
consumer-jpeg.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69307 91177308-0d34-0410-b5e6-96231b3b80d8
not create ICmpInsts with operands of different types. This fixes
a regression in Applications/d/make_dparser.
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have pointer types, though in contrast to C pointer types, SCEV
addition is never implicitly scaled. This not only eliminates the
need for special code like IndVars' EliminatePointerRecurrence
and LSR's own GEP expansion code, it also does a better job because
it lets the normal optimizations handle pointer expressions just
like integer expressions.
Also, since LLVM IR GEPs can't directly index into multi-dimensional
VLAs, moving the GEP analysis out of client code and into the SCEV
framework makes it easier for clients to handle multi-dimensional
VLAs the same way as other arrays.
Some existing regression tests show improved optimization.
test/CodeGen/ARM/2007-03-13-InstrSched.ll in particular improved to
the point where if-conversion started kicking in; I turned it off
for this test to preserve the intent of the test.
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and sext over (iv | const), if a longer iv is
available. Allow expressions to have more than
one zext/sext parent. All from OpenSSL.
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to support replacing a node with another that has a superset of
the result types. Use this instead of calling
ReplaceAllUsesOfValueWith for each value.
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sext around sext(shorter IV + constant), using a
longer IV instead, when it can figure out the
add can't overflow. This comes up a lot in
subscripting; mainly affects 64 bit.
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llvm.dbg.region.end instrinsic. This nested llvm.dbg.func.start/llvm.dbg.region.end pair now enables DW_TAG_inlined_subroutine support in code generator.
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either the source or destination is a physical h register.
This fixes sqlite3 with the post-RA scheduler enabled.
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operator is used by a CopyToReg to export the value to a different
block, don't reuse the CopyToReg's register for the subreg operation
result if the register isn't precisely the right class for the
subreg operation.
Also, rename the h-registers.ll test, now that there are more
than one.
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Makes llvmc show error messages printed by child processes when run from the
Cygwin/MSYS shell. Since ExecuteAndWait does not return until the child program
has finished execution, this change should be harmless.
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promoted to legal types without changing the type of the vector. This is
following a suggestion from Duncan
(http://lists.cs.uiuc.edu/pipermail/llvmdev/2009-February/019923.html).
The transformation that used to be done during type legalization is now
postponed to DAG legalization. This allows the BUILD_VECTORs to be optimized
and potentially handled specially by target-specific code.
It turns out that this is also consistent with an optimization done by the
DAG combiner: a BUILD_VECTOR and INSERT_VECTOR_ELT may be combined by
replacing one of the BUILD_VECTOR operands with the newly inserted element;
but INSERT_VECTOR_ELT allows its scalar operand to be larger than the
element type, with any extra high bits being implicitly truncated. The
result is a BUILD_VECTOR where one of the operands has a type larger the
the vector element type.
Any code that operates on BUILD_VECTORs may now need to be aware of the
potential type discrepancy between the vector element type and the
BUILD_VECTOR operands. This patch updates all of the places that I could
find to handle that case.
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Now debug_inlined section is covered by TAI->doesDwarfUsesInlineInfoSection(), which is false by default.
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- Add patterns for h-register extract, which avoids a shift and mask,
and in some cases a temporary register.
- Add address-mode matching for turning (X>>(8-n))&(255<<n), where
n is a valid address-mode scale value, into an h-register extract
and a scaled-offset address.
- Replace X86's MOV32to32_ and related instructions with the new
target-independent COPY_TO_SUBREG instruction.
On x86-64 there are complicated constraints on h registers, and
CodeGen doesn't currently provide a high-level way to express all of them,
so they are handled with a bunch of special code. This code currently only
supports extracts where the result is used by a zero-extend or a store,
though these are fairly common.
These transformations are not always beneficial; since there are only
4 h registers, they sometimes require extra move instructions, and
this sometimes increases register pressure because it can force out
values that would otherwise be in one of those registers. However,
this appears to be relatively uncommon.
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This will be used to replace things like X86's MOV32to32_.
Enhance ScheduleDAGSDNodesEmit to be more flexible and robust
in the presense of subregister superclasses and subclasses. It
can now cope with the definition of a virtual register being in
a subclass of a use.
Re-introduce the code for recording register superreg classes and
subreg classes. This is needed because when subreg extracts and
inserts get coalesced away, the virtual registers are left in
the correct subclass.
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ISD::SIGN_EXTEND_INREG. Tablegen-generated code can handle
these cases, and the scheduling issues observed earlier
appear to be resolved now.
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the subreg field to 0, since the subreg field is only used
for virtual register subregs. This doesn't change
current functionality; it just eliminates bogus noise from
debug output.
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to support C99 inline, GNU extern inline, etc. Related bugzilla's
include PR3517, PR3100, & PR2933. Nothing uses this yet, but it
appears to work.
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strncat :(
strncat(foo, "bar", 99)
would be optimized to
memcpy(foo+strlen(foo), "bar", 100, 1)
instead of
memcpy(foo+strlen(foo), "bar", 4, 1)"
Patch by Benjamin Kramer!
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Create debug_inlined dwarf section using these information. This info is used by gdb, at least on Darwin, to enable better experience debugging inlined functions. See DwarfWriter.cpp for more information on structure of debug_inlined section.
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1. Sinking would crash when the first instruction of a block was
sunk due to iterator problems.
2. Instructions could be sunk to their current block, causing an
infinite loop.
This fixes PR3968
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the key. This will cause it to create a new std::string, which isn't
wanted. Instead, pass back the "const char*". Modify the EmitString() method to
take a "const char*".
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register destinations that are tied to source operands. The
TargetInstrDescr::findTiedToSrcOperand method silently fails for inline
assembly. The existing MachineInstr::isRegReDefinedByTwoAddr was very
close to doing what is needed, so this revision makes a few changes to
that method and also renames it to isRegTiedToUseOperand (for consistency
with the very similar isRegTiedToDefOperand and because it handles both
two-address instructions and inline assembly with tied registers).
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in addition to ZERO_EXTEND and SIGN_EXTEND. Fix a bug in the
way it checked for live-out values, and simplify the way it
find users by using SDNode::use_iterator's (relatively) new
features. Also, make it slightly more permissive on targets
with free truncates.
In SelectionDAGBuild, avoid creating ANY_EXTEND nodes that are
larger than necessary. If the target's SwitchAmountTy has
enough bits, use it. This exposes the truncate to optimization
early, enabling more optimizations.
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eagerly. This helps avoid CopyToReg nodes in some cases where they
aren't needed, and also helps subsequent optimizer heuristics
in cases where the extra nodes would cause the node to appear
to have multiple results. This doesn't have a significant impact
currently; it'll help an upcoming change.
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integer types, unless they are already strange. This prevents it from
turning the code produced by SROA into crazy libcalls and stuff that
the code generator can't handle. In the attached example, the result
was an i96 multiply that caused the x86 backend to assert.
Note that if TargetData had an idea of what the legal types are for
a target that this could be used to stop instcombine from introducing
i64 muls, as Scott wanted.
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Every function has the address of its frame in the beginning of code section.
The frame address is retrieved and used to pass arguments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@68597 91177308-0d34-0410-b5e6-96231b3b80d8
avoiding sign extension for the top octet. For "negative" chars, we'd print
stuff like:
.asciz "\702...
now we print:
.asciz "\302...
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with SUBREG_TO_REG, teach SimpleRegisterCoalescing to coalesce
SUBREG_TO_REG instructions (which are similar to INSERT_SUBREG
instructions), and teach the DAGCombiner to take advantage of this on
targets which support it. This eliminates many redundant
zero-extension operations on x86-64.
This adds a new TargetLowering hook, isZExtFree. It's similar to
isTruncateFree, except it only applies to actual definitions, and not
no-op truncates which may not zero the high bits.
Also, this adds a new optimization to SimplifyDemandedBits: transform
operations like x+y into (zext (add (trunc x), (trunc y))) on targets
where all the casts are no-ops. In contexts where the high part of the
add is explicitly masked off, this allows the mask operation to be
eliminated. Fix the DAGCombiner to avoid undoing these transformations
to eliminate casts on targets where the casts are no-ops.
Also, this adds a new two-address lowering heuristic. Since
two-address lowering runs before coalescing, it helps to be able to
look through copies when deciding whether commuting and/or
three-address conversion are profitable.
Also, fix a bug in LiveInterval::MergeInClobberRanges. It didn't handle
the case that a clobber range extended both before and beyond an
existing live range. In that case, multiple live ranges need to be
added. This was exposed by the new subreg coalescing code.
Remove 2008-05-06-SpillerBug.ll. It was bugpoint-reduced, and the
spiller behavior it was looking for no longer occurrs with the new
instruction selection.
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builds.
--- Reverse-merging (from foreign repository) r68552 into '.':
U test/CodeGen/X86/tls8.ll
U test/CodeGen/X86/tls10.ll
U test/CodeGen/X86/tls2.ll
U test/CodeGen/X86/tls6.ll
U lib/Target/X86/X86Instr64bit.td
U lib/Target/X86/X86InstrSSE.td
U lib/Target/X86/X86InstrInfo.td
U lib/Target/X86/X86RegisterInfo.cpp
U lib/Target/X86/X86ISelLowering.cpp
U lib/Target/X86/X86CodeEmitter.cpp
U lib/Target/X86/X86FastISel.cpp
U lib/Target/X86/X86InstrInfo.h
U lib/Target/X86/X86ISelDAGToDAG.cpp
U lib/Target/X86/AsmPrinter/X86ATTAsmPrinter.cpp
U lib/Target/X86/AsmPrinter/X86IntelAsmPrinter.cpp
U lib/Target/X86/AsmPrinter/X86ATTAsmPrinter.h
U lib/Target/X86/AsmPrinter/X86IntelAsmPrinter.h
U lib/Target/X86/X86ISelLowering.h
U lib/Target/X86/X86InstrInfo.cpp
U lib/Target/X86/X86InstrBuilder.h
U lib/Target/X86/X86RegisterInfo.td
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This introduces a small regression on the generated code
quality in the case we are just computing addresses, not
loading values.
Will work on it and on X86-64 support.
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When compiling in Thumb mode, only the low (R0-R7) registers are available
for most instructions. Breaking the low registers into a new register class
handles this. Uses of R12, SP, etc, are handled explicitly where needed
with copies inserted to move results into low registers where the rest of
the code generator can deal with them.
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instead of the place where it started to perform the string copy.
- PR3661
- Patch by Benjamin Kramer!
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Constant, MDString and MDNode which can only be used by globals with a name
that starts with "llvm." or as arguments to a function with the same naming
restriction.
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Note that these are distinct from TargetInstrInfo::INSERT_SUBREG
and TargetInstrInfo::EXTRACT_SUBREG, which are used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@68355 91177308-0d34-0410-b5e6-96231b3b80d8
- The code is silly, I'm just amusing myself. Rewrite to be efficient
if you like. :)
Also, if you wish to debate the proper names of the triple components
I'm all ears.
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is appropriate. This helps visually differentiate host-oriented
calculations from target-oriented calculations.
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which are effectively smart pointers to Value*'s. They are both very light
weight and simple, and react to values being destroyed or being RAUW'd.
WeakVN does a best effort to follow a value around, including through RAUW
operations and will get nulled out of the value is destroyed. This is useful
for the eventual "metadata that references a value" work, because it is a
reference to a value that does not show up on its use_* list.
AssertingVH is a pointer that compiles down to a dumb raw pointer when
assertions are disabled. When enabled, it emits an assertion if the
pointed-to value is destroyed while it is still being referenced. This
is very useful for Maps and other things, and should have caught the recent
bugs in CallGraph and Reassociate, for example.
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entered via fall-through. Don't miss fallthroughs from blocks
terminated by conditional branches. Also, move
isOnlyReachableByFallthrough out of line.
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llvm::sys::getOS{Name,Version}.
Right now the implementation just derives from LLVM_HOSTTRIPLE (which
is wrong, but it doesn't look like we have a define for the target
triple). Ideally this routine would actually be able to compute the
triple for targets we care about.
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only reachable via fall-through edges. This dramatically reduces the
number of labels printed, and thus also the number of labels the
assembler must parse and remember.
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e.g.
%reg1024<def> = MOV r1
%reg1025<def> = ADD %reg1024, %reg1026
r0 = MOV %reg1025
If it's not possible / profitable to commute ADD, then turning ADD into a LEA saves a copy.
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x * 40
=>
shlq $3, %rdi
leaq (%rdi,%rdi,4), %rax
This has the added benefit of allowing more multiply to be folded into addressing mode. e.g.
a * 24 + b
=>
leaq (%rdi,%rdi,2), %rax
leaq (%rsi,%rax,8), %rax
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%a = ...
%b = and i32 %a, 2
%c = srl i32 %b, 1
%d = br i32 %c,
into
%a = ...
%b = and %a, 2
%c = X86ISD::CMP %b, 0
%d = X86ISD::BRCOND %c ...
This applies only when the AND constant value has one bit set and the SRL
constant is equal to the log2 of the AND constant. The back-end is smart enough
to convert the result into a TEST/JMP sequence.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67728 91177308-0d34-0410-b5e6-96231b3b80d8
Also fixes SDISel so it *does not* force promote return value if the function is not marked signext / zeroext.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67701 91177308-0d34-0410-b5e6-96231b3b80d8
stoppoint nodes around until Legalize; doing this
imposed an ordering on a sequence of loads that
came from different lines, interfering with scheduling.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67692 91177308-0d34-0410-b5e6-96231b3b80d8
call, we should treat "i64 zext" as the start of a constant expr, but
"i64 0 zext" as an argument with an obsolete attribute on it (this form
is already tested by test/Assembler/2007-07-30-AutoUpgradeZextSext.ll).
Make the autoupgrade logic more discerning to avoid treating "i64 zext"
as an old-style attribute, causing us to reject a valid constant expr.
This fixes PR3876.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67682 91177308-0d34-0410-b5e6-96231b3b80d8
