argument of the llvm.dbg.declare/llvm.dbg.value intrinsics.
Previously, DIVariable was a variable-length field that has an optional
reference to a Metadata array consisting of a variable number of
complex address expressions. In the case of OpPiece expressions this is
wasting a lot of storage in IR, because when an aggregate type is, e.g.,
SROA'd into all of its n individual members, the IR will contain n copies
of the DIVariable, all alike, only differing in the complex address
reference at the end.
By making the complex address into an extra argument of the
dbg.value/dbg.declare intrinsics, all of the pieces can reference the
same variable and the complex address expressions can be uniqued across
the CU, too.
Down the road, this will allow us to move other flags, such as
"indirection" out of the DIVariable, too.
The new intrinsics look like this:
declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr)
declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr)
This patch adds a new LLVM-local tag to DIExpressions, so we can detect
and pretty-print DIExpression metadata nodes.
What this patch doesn't do:
This patch does not touch the "Indirect" field in DIVariable; but moving
that into the expression would be a natural next step.
http://reviews.llvm.org/D4919
rdar://problem/17994491
Thanks to dblaikie and dexonsmith for reviewing this patch!
llvm-svn: 218778
This is the final round of renaming. This changes tblgen to emit lower-case
function names for FastEmitInst_* and FastEmit_*, and updates all its uses
in the source code.
Reviewed by Eric
llvm-svn: 217075
Note: This was originally reverted to track down a buildbot error. Reapply
without any modifications.
Original commit message:
In the large code model for X86 floating-point constants are placed in the
constant pool and materialized by loading from it. Since the constant pool
could be far away, a PC relative load might not work. Therefore we first
materialize the address of the constant pool with a movabsq and then load
from there the floating-point value.
Fixes <rdar://problem/17674628>.
llvm-svn: 216012
Note: This was originally reverted to track down a buildbot error. Reapply
without any modifications.
Original commit message:
This mostly affects the i64 value type, which always resulted in an 15byte
mobavsq instruction to materialize any constant. The custom code checks the
value of the immediate and tries to use a different and smaller mov
instruction when possible.
This fixes <rdar://problem/17420988>.
llvm-svn: 216010
This reverts:
r215595 "[FastISel][X86] Add large code model support for materializing floating-point constants."
r215594 "[FastISel][X86] Use XOR to materialize the "0" value."
r215593 "[FastISel][X86] Emit more efficient instructions for integer constant materialization."
r215591 "[FastISel][AArch64] Make use of the zero register when possible."
r215588 "[FastISel] Let the target decide first if it wants to materialize a constant."
r215582 "[FastISel][AArch64] Cleanup constant materialization code. NFCI."
llvm-svn: 215673
In the large code model for X86 floating-point constants are placed in the
constant pool and materialized by loading from it. Since the constant pool
could be far away, a PC relative load might not work. Therefore we first
materialize the address of the constant pool with a movabsq and then load
from there the floating-point value.
Fixes <rdar://problem/17674628>.
llvm-svn: 215595
This mostly affects the i64 value type, which always resulted in an 15byte
mobavsq instruction to materialize any constant. The custom code checks the
value of the immediate and tries to use a different and smaller mov
instruction when possible.
This fixes <rdar://problem/17420988>.
llvm-svn: 215593
Split the constant materialization code into three separate helper functions for
Integer-, Floating-Point-, and GlobalValue-Constants.
llvm-svn: 215586
I accidentally also used INC/DEC for unsigned arithmetic which doesn't work,
because INC/DEC don't set the required flag which is used for the overflow
check.
llvm-svn: 215237
to get the subtarget and that's accessible from the MachineFunction
now. This helps clear the way for smaller changes where we getting
a subtarget will require passing in a MachineFunction/Function as
well.
llvm-svn: 214988
Stop using ST registers for function returns and inline-asm instructions and use
FP registers instead. This allows removing a large amount of code in the
stackifier pass that was needed to track register liveness and handle copies
between ST and FP registers and function calls returning floating point values.
It also fixes a bug which manifests when an ST register defined by an
inline-asm instruction was live across another inline-asm instruction, as shown
in the following sequence of machine instructions:
1. INLINEASM <es:frndint> $0:[regdef], %ST0<imp-def,tied5>
2. INLINEASM <es:fldcw $0>
3. %FP0<def> = COPY %ST0
<rdar://problem/16952634>
llvm-svn: 214580
UNDEF arguments are not ment to be touched - especially for the webkit_js
calling convention. This fix reproduces the already existing behavior of
SelectionDAG in FastISel.
llvm-svn: 214366
Fixes a gcc warning caused by a typo. A redundant assignment operation was
accidentally used as the third operand of a conditional expression.
No functional change intended.
llvm-svn: 213061
This implements the FastLowerCall hook, which is based on the DoSelectCall
function. The implementation is very similar, but the target-independent call
lowering part has been factored out.
This should also enable patchpoint intrinsic lowering for FastISel on X86.
Related to <rdar://problem/17427052>.
llvm-svn: 213049
Revert "[FastISel][X86] Implement the FastLowerIntrinsicCall hook."
Revert "[FastISel][X86] Implement the FastLowerCall hook."
This reverts commit r213035, r213036, and r213037 to make the
buildbots happy again.
llvm-svn: 213048
This implements the FastLowerCall hook, which is based on the DoSelectCall
function. The implementation is very similar, but the target-independent call
lowering part has been factored out.
This should also enable patchpoint intrinsic lowering for FastISel on X86.
Related to <rdar://problem/17427052>.
llvm-svn: 213035
Add custom lowering code for signed multiply instruction selection, because the
default FastISel instruction selection for ISD::MUL will use unsigned multiply
for the i8 type and signed multiply for all other types. This would set the
incorrect flags for the overflow check.
This fixes <rdar://problem/17549300>
llvm-svn: 212493
We've been performing the wrong operation on ARM for "atomicrmw nand" for
years, since "a NAND b" is "~(a & b)" rather than ARM's very tempting "a & ~b".
This bled over into the generic expansion pass.
So I assume no-one has ever actually tried to do an atomic nand in the real
world. Oh well.
llvm-svn: 212443
If the cmp is in a different basic block, then it is possible that not all
operands of that compare have defined registers. This can happen when one of
the operands to the cmp is a load and the load gets folded into the cmp. In
this case FastISel will skip the load instruction and the vreg is never
defined.
llvm-svn: 211730
Optimize the codegen of select and branch instructions to directly use the
EFLAGS from the {s|u}{add|sub|mul}.with.overflow intrinsics.
llvm-svn: 211645
The extends the select lowering coverage by emiting pseudo cmov
instructions. These insturction will be later on lowered to control-flow to
simulate the select.
llvm-svn: 211545
This extends the select lowering to support floating-point selects. The
lowering depends on SSE instructions and that the conditon comes from a
floating-point compare. Under this conditions it is possible to emit an
optimized instruction sequence that doesn't require any branches to
simulate the select.
llvm-svn: 211544
This patch is a follow up to r211040 & r211052. Rather than bailing out of fast
isel this patch will generate an alternate instruction (movabsq) instead of the
leaq. While this will always have enough room to handle the 64 bit displacment
it is generally over kill for internal symbols (most displacements will be
within 32 bits) but since we have no way of communicating the code model to the
the assmebler in order to avoid flagging an absolute leal/leaq as illegal when
using a symbolic displacement.
llvm-svn: 211130
This optimizes predicates for certain compares, such as fcmp oeq %x, %x to
fcmp ord %x, %x. The latter one is more efficient to generate.
The same optimization is applied to conditional branches.
llvm-svn: 211126
Make use of helper functions to simplify the branch and compare instruction
selection in FastISel. Also add test cases for compare and conditonal branch.
llvm-svn: 211077
Added comment to clarify why we r211040 choose to bail out of fast isel instead
of generating a more complicated relocation, and fix mislabelled register in the
comments of the asan test case.
llvm-svn: 211052
On x86_86 the lea instruction can only use a 32 bit immediate value. When
the code is compiled statically the RIP register is not used, meaning the
immediate is all that can be used for the relocation, which is not sufficient
in the case of targets more than +/- 2GB away. This patch bails out of fast
isel in those cases and reverts to DAG which does the right thing.
Test case included.
llvm-svn: 211040
This adds support for the cvttss2si/cvttsd2si intrinsics. Preceding
insertelement instructions are folded into the conversion instruction (if
possible).
llvm-svn: 210870
This commit adds MachineMemOperands to load and store instructions. This allows
the peephole optimizer to fold load instructions. Unfortunatelly the peephole
optimizer currently doesn't run at -O0.
llvm-svn: 210858
This matches gcc's behavior. It also seems natural given that aliases
contain other properties that govern how it is accessed (linkage,
visibility, dll storage).
Clang still has to be updated to expose this feature to C.
llvm-svn: 209759
This adds back r204781.
Original message:
Aliases are just another name for a position in a file. As such, the
regular symbol resolutions are not applied. For example, given
define void @my_func() {
ret void
}
@my_alias = alias weak void ()* @my_func
@my_alias2 = alias void ()* @my_alias
We produce without this patch:
.weak my_alias
my_alias = my_func
.globl my_alias2
my_alias2 = my_alias
That is, in the resulting ELF file my_alias, my_func and my_alias are
just 3 names pointing to offset 0 of .text. That is *not* the
semantics of IR linking. For example, linking in a
@my_alias = alias void ()* @other_func
would require the strong my_alias to override the weak one and
my_alias2 would end up pointing to other_func.
There is no way to represent that with aliases being just another
name, so the best solution seems to be to just disallow it, converting
a miscompile into an error.
llvm-svn: 204934
This reverts commit r204781.
I will follow up to with msan folks to see what is what they
were trying to do with aliases to weak aliases.
llvm-svn: 204784
Aliases are just another name for a position in a file. As such, the
regular symbol resolutions are not applied. For example, given
define void @my_func() {
ret void
}
@my_alias = alias weak void ()* @my_func
@my_alias2 = alias void ()* @my_alias
We produce without this patch:
.weak my_alias
my_alias = my_func
.globl my_alias2
my_alias2 = my_alias
That is, in the resulting ELF file my_alias, my_func and my_alias are
just 3 names pointing to offset 0 of .text. That is *not* the
semantics of IR linking. For example, linking in a
@my_alias = alias void ()* @other_func
would require the strong my_alias to override the weak one and
my_alias2 would end up pointing to other_func.
There is no way to represent that with aliases being just another
name, so the best solution seems to be to just disallow it, converting
a miscompile into an error.
llvm-svn: 204781
name might indicate, it is an iterator over the types in an instruction
in the IR.... You see where this is going.
Another step of modularizing the support library.
llvm-svn: 202815
Calls with inalloca are lowered by skipping all stores for arguments
passed in memory and the initial stack adjustment to allocate argument
memory.
Now the frontend is responsible for the memory layout, and the backend
doesn't have to do any work. As a result these changes are pretty
minimal.
Reviewers: echristo
Differential Revision: http://llvm-reviews.chandlerc.com/D2637
llvm-svn: 200596
Allocas marked inalloca are never static, but we were trying to put them
into the static alloca map if they were in the entry block. Also add an
assertion in x86 fastisel.
llvm-svn: 200593
promotion code, Tablegen will now select FPExt for floating point promotions
(previously it had returned AExt, which is not valid for floating point types).
Any out-of-tree targets that were relying on AExt being returned for FP
promotions will need to update their code check for FPExt instead.
llvm-svn: 199252
Representing dllexport/dllimport as distinct linkage types prevents using
these attributes on templates and inline functions.
Instead of introducing further mixed linkage types to include linkonce and
weak ODR, the old import/export linkage types are replaced with a new
separate visibility-like specifier:
define available_externally dllimport void @f() {}
@Var = dllexport global i32 1, align 4
Linkage for dllexported globals and functions is now equal to their linkage
without dllexport. Imported globals and functions must be either
declarations with external linkage, or definitions with
AvailableExternallyLinkage.
llvm-svn: 199218
Representing dllexport/dllimport as distinct linkage types prevents using
these attributes on templates and inline functions.
Instead of introducing further mixed linkage types to include linkonce and
weak ODR, the old import/export linkage types are replaced with a new
separate visibility-like specifier:
define available_externally dllimport void @f() {}
@Var = dllexport global i32 1, align 4
Linkage for dllexported globals and functions is now equal to their linkage
without dllexport. Imported globals and functions must be either
declarations with external linkage, or definitions with
AvailableExternallyLinkage.
llvm-svn: 199204
I couldn't see how to do this sanely without splitting RETQ from RETL.
Eric says: "sad about the inability to roundtrip them now, but...".
I have no idea what that means, but perhaps it wants preserving in the
commit comment.
llvm-svn: 198756
The condition in selects is supposed to be i1.
Make sure we are just reading the less significant bit
of the 8 bits width value to match this constraint.
<rdar://problem/15651765>
llvm-svn: 197712
This changes the MachineFrameInfo API to use the new SSPLayoutKind information
produced by the StackProtector pass (instead of a boolean flag) and updates a
few pass dependencies (to preserve the SSP analysis).
The stack layout follows the same approach used prior to this change - i.e.,
only LargeArray stack objects will be placed near the canary and everything
else will be laid out normally. After this change, structures containing large
arrays will also be placed near the canary - a case previously missed by the
old implementation.
Out of tree targets will need to update their usage of
MachineFrameInfo::CreateStackObject to remove the MayNeedSP argument.
The next patch will implement the rules for sspstrong and sspreq. The end goal
is to support ssp-strong stack layout rules.
WIP.
Differential Revision: http://llvm-reviews.chandlerc.com/D2158
llvm-svn: 197653
Stop folding constant adds into GEP when the type size doesn't match.
Otherwise, the adds' operands are effectively being promoted, changing the
conditions of an overflow. Results are different when:
sext(a) + sext(b) != sext(a + b)
Problem originally found on x86-64, but also fixed issues with ARM and PPC,
which used similar code.
<rdar://problem/15292280>
Patch by Duncan Exon Smith!
llvm-svn: 194840
The idea of the AnyReg Calling Convention is to provide the call arguments in
registers, but not to force them to be placed in a paticular order into a
specified set of registers. Instead it is up tp the register allocator to assign
any register as it sees fit. The same applies to the return value (if
applicable).
Differential Revision: http://llvm-reviews.chandlerc.com/D2009
Reviewed by Andy
llvm-svn: 194293
through bitcast, ptrtoint, and inttoptr instructions. This is valid
only if the related instructions are in that same basic block, otherwise
we may reference variables that were not live accross basic blocks
resulting in undefined virtual registers.
The bug was exposed when both SDISel and FastISel were used within the same
function, i.e., one basic block is issued with FastISel and another with SDISel,
as demonstrated with the testcase.
<rdar://problem/15192473>
llvm-svn: 192636
Make sure that the code that handles the constant addresses is run for the
GEPs. This just refactors that code and then calls it for the GEPs that are
collected during the iteration.
<rdar://problem/12445434>
llvm-svn: 191281
The recursive nature of the address selection code can cause the stack to
explode if there is a long chain of GEPs. Convert the recursive bit into a
iterative method to avoid this.
<rdar://problem/12445434>
llvm-svn: 191252
Summary:
This patch adds explicit calling convention types for the Win64 and
System V/x86-64 ABIs. This allows code to override the default, and use
the Win64 convention on a target that wants to use SysV (and
vice-versa). This is needed to implement the `ms_abi` and `sysv_abi` GNU
attributes.
Reviewers:
CC:
llvm-svn: 186144
Explicit references to %AH for an i8 remainder instruction can lead to
references to %AH in a REX prefixed instruction, which causes things to
blow up. Do the same thing in FastISel as we do for DAG isel and instead
shift %AX right by 8 bits and then extract the 8-bit subreg from that
result.
rdar://14203849
http://llvm.org/bugs/show_bug.cgi?id=16105
llvm-svn: 185899
A FastISel optimization was causing us to emit no information for such
parameters & when they go missing we end up emitting a different
function type. By avoiding that shortcut we not only get types correct
(very important) but also location information (handy) - even if it's
only live at the start of a function & may be clobbered later.
Reviewed/discussion by Evan Cheng & Dan Gohman.
llvm-svn: 184604
