the "identifier" parsed by the frontend callback by skipping forward
until we've consumed a token that ends at the point dictated by the
callback.
In addition, inform the callback when it's parsing an unevaluated
operand (e.g. mov eax, LENGTH A::x) as opposed to an evaluated one
(e.g. mov eax, [A::x]).
This commit depends on a clang commit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180978 91177308-0d34-0410-b5e6-96231b3b80d8
Clarify documentation and API to make the difference between register and
register-indirect addressed locations more explicit. Put in a comment
to point out that with the current implementation we cannot specify
a register-indirect location with offset 0 (a breg 0 in DWARF).
No functionality change intended.
rdar://problem/13658587
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now taken care of by the frontend, which allows us to parse arbitrary C/C++
variables.
Part of rdar://13663589
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Add support for the COFF relocation types IMAGE_REL_I386_DIR32NB and
IMAGE_REL_AMD64_ADDR32NB for 32- and 64-bit respectively. These are
similar to normal 4-byte relocations except that they do not include
the base address of the image.
Image-relative relocations are used for debug information (32-bit) and
SEH unwind tables (64-bit).
A new MCSymbolRef variant called 'VK_COFF_IMGREL32' is introduced to
specify such relocations. For AT&T assembly, this variant can be accessed
using the symbol suffix '@imgrel'.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179240 91177308-0d34-0410-b5e6-96231b3b80d8
Compact unwind has an encoding for when we're not able to generate compact
unwind and must generate an EH frame instead. Track that, but still emit that CU
encoding.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179220 91177308-0d34-0410-b5e6-96231b3b80d8
Test cases that regressed due to r179115, plus a few more, were added in
r179182. Original commit message below:
[ms-inline asm] Use parsePrimaryExpr in lieu of parseExpression if we need to
parse an identifier. Otherwise, parseExpression may parse multiple tokens,
which makes it impossible to properly compute an immediate displacement.
An example of such a case is the source operand (i.e., [Symbol + ImmDisp]) in
the below example:
__asm mov eax, [Symbol + ImmDisp]
Part of rdar://13611297
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179187 91177308-0d34-0410-b5e6-96231b3b80d8
parse an identifier. Otherwise, parseExpression may parse multiple tokens,
which makes it impossible to properly compute an immediate displacement.
An example of such a case is the source operand (i.e., [Symbol + ImmDisp]) in
the below example:
__asm mov eax, [Symbol + ImmDisp]
The existing test cases exercise this patch.
rdar://13611297
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179115 91177308-0d34-0410-b5e6-96231b3b80d8
rather than deriving the StringRef from the Start and End SMLocs.
Using the Start and End SMLocs works fine for operands such as [Symbol], but
not for operands such as [Symbol + ImmDisp]. All existing test cases that
reference a variable exercise this patch.
rdar://13602265
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179109 91177308-0d34-0410-b5e6-96231b3b80d8
We now emit a line table for each compile unit. To reduce the prologue size
of each line table, the files and directories used by each compile unit are
stored in std::map<unsigned, std::vector< > > instead of std::vector< >.
The prologue for a lto'ed image can be as big as 93K. Duplicating 93K for each
compile unit causes a huge increase of debug info. With this patch, each
prologue will only emit the files required by the compile unit.
rdar://problem/13342023
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excluding visibility bits.
Generic STO handling at the Target level.
The st_other field of the ELF symbol table is one
byte in size. The first 2 bytes are used for generic
visibility and are currently handled by llvm.
The other six bits are processor specific and need
to be set at the target level.
A couple of notes:
The new static methods for accessing and setting the "other"
flags in include/llvm/MC/MCELF.h match the style guide
and not the other methods in the file. I don't like the
inconsistency, but feel I should follow the prescribed
lowerUpper() convention.
STO_ value definitions are not specified in gnu land as
consistently as the STT_ and STB_ fields. Probably because
the latter were defined in a standards doc and the former
defined partially in code. I have stuck with the full byte
definition of the flags.
Contributer: Zoran Jovanovic
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Also, allow _EMIT and __EMIT for the emit directive. We already do the same
for TYPE, SIZE, and LENGTH.
rdar://13200215
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I have some uncommitted changes to the cast code that catch this sort of thing
at compile-time but I still need to do some other cleanup before I can enable
it.
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For example, ARM has several instructions with a literal '#0' immediate in the syntax
that's not represented as an actual operand. The asm matcher is expected a token
operand, but the parser will have created an immediate operand. This is currently
handled by dedicated per-instruction C++ munging of the ParsedAsmOperand list, but
will be better handled by this hook.
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We generate one line table for each compilation unit in the object file.
Reviewed by Eric and Kevin.
rdar://problem/13067005
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Currently, when a fragment is relaxed, its size is modified, but its
offset is not (it gets laid out as a side effect of checking whether
it needs relaxation), then all subsequent fragments are invalidated
because their offsets need to change. When bundling is enabled,
relaxed fragments need to get laid out again, because the increase in
size may push it over a bundle boundary. So instead of only
invalidating subsequent fragments, also invalidate the fragment that
gets relaxed, which causes it to get laid out again.
This patch also fixes some trailing whitespace and fixes the
bundling-related debug output of MCFragments.
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caught this, but I want that in a separate commit in case there is
a need to revert the actual functional bit as part of reverting other
patches. This way, the commits relating to just getting the RTTI bits in
place are separate from the functional changes that start using them.
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isa<> and dyn_cast<>. In several places, code is already hacking around
the absence of this, and there seem to be several interfaces that might
be lifted and/or devirtualized using this.
This change was based on a discussion with Jim Grosbach about how best
to handle testing for specific MCStreamer subclasses. He said that this
was the correct end state, and everything else was too hacky so
I decided to just make it so.
No functionality should be changed here, this is just threading the kind
through all the constructors and setting up the classof overloads.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174113 91177308-0d34-0410-b5e6-96231b3b80d8
This patch adds support for AArch64 (ARM's 64-bit architecture) to
LLVM in the "experimental" category. Currently, it won't be built
unless requested explicitly.
This initial commit should have support for:
+ Assembly of all scalar (i.e. non-NEON, non-Crypto) instructions
(except the late addition CRC instructions).
+ CodeGen features required for C++03 and C99.
+ Compilation for the "small" memory model: code+static data <
4GB.
+ Absolute and position-independent code.
+ GNU-style (i.e. "__thread") TLS.
+ Debugging information.
The principal omission, currently, is performance tuning.
This patch excludes the NEON support also reviewed due to an outbreak of
batshit insanity in our legal department. That will be committed soon bringing
the changes to precisely what has been approved.
Further reviews would be gratefully received.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174054 91177308-0d34-0410-b5e6-96231b3b80d8
and update ELF header e_flags.
Currently gathering information such as symbol,
section and data is done by collecting it in an
MCAssembler object. From MCAssembler and MCAsmLayout
objects ELFObjectWriter::WriteObject() forms and
streams out the ELF object file.
This patch just adds a few members to the MCAssember
class to store and access the e_flag settings. It
allows for runtime additions to the e_flag by
assembler directives. The standalone assembler can
get to MCAssembler from getParser().getStreamer().getAssembler().
This patch is the generic infrastructure and will be
followed by patches for ARM and Mips for their target
specific use.
Contributer: Jack Carter
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173882 91177308-0d34-0410-b5e6-96231b3b80d8
Add the x32 environment kind to the triple, and separate the concept of
pointer size and callee save stack slot size, since they're not equal
on x32.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173175 91177308-0d34-0410-b5e6-96231b3b80d8
AT_producer. Which includes clang's version information so we can tell
which version of the compiler was used.
This is the first of two steps to allow us to do that. This is the llvm-mc
change to provide a method to set the AT_producer string. The second step,
coming soon to a clang near you, will have the clang driver pass the value
of getClangFullVersion() via an flag when invoking the integrated assembler
on assembly source files.
rdar://12955296
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Since we already have this type it's a shame to keep dragging a pair of object
and method around explicitly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172584 91177308-0d34-0410-b5e6-96231b3b80d8
using the DW_FORM_GNU_addr_index and a separate .debug_addr section which
stays in the executable and is fully linked.
Sneak in two other small changes:
a) Print out the debug_str_offsets.dwo section.
b) Change form we're expecting the entries in the debug_str_offsets.dwo
section to take from ULEB128 to U32.
Add tests for all of this in the fission-cu.ll test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172578 91177308-0d34-0410-b5e6-96231b3b80d8
into which we can emit single instructions without fixups (which is most
instructions). This is an optimization required because MCDataFragment
is prety large (240 bytes on x64), with no change in functionality.
For large programs, this reduces memory usage overhead required for bundling
by 40%.
To make the code as palatable as possible, the MCEncodedFragment interface was
further fragmented (no pun intended) and MCEncodedFragmentWithFixups is used
as the interface to work against when the user expects fixups. MCDataFragment
and MCRelaxableFragment implement this interface, while the new
MCCompactEncodedInstFragment implements MCEncodeFragment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172572 91177308-0d34-0410-b5e6-96231b3b80d8
This finally allows AsmParser to no longer list GenericAsmParser as a friend.
All member vars directly accessed by GenericAsmParser have been properly
encapsulated and exposed through the MCAsmParser interface. This reduces the
coupling between AsmParser and GenericAsmParser.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172490 91177308-0d34-0410-b5e6-96231b3b80d8
Now that it behaves itself in terms of streamer independence (r172450), this
method can be moved to MCAsmParser to be available to all extensions,
overriding, etc.
-- -This line, and those below, will be ignored--
M lib/MC/MCParser/AsmParser.cpp
M include/llvm/MC/MCParser/MCAsmParser.h
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172451 91177308-0d34-0410-b5e6-96231b3b80d8
The aim of this patch is to fix the following piece of code in the
platform-independent AsmParser:
void AsmParser::CheckForValidSection() {
if (!ParsingInlineAsm && !getStreamer().getCurrentSection()) {
TokError("expected section directive before assembly directive");
Out.SwitchSection(Ctx.getMachOSection(
"__TEXT", "__text",
MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
0, SectionKind::getText()));
}
}
This was added for the "-n" option of llvm-mc.
The proposed fix adds another virtual method to MCStreamer, called
InitToTextSection. Conceptually, it's similar to the existing
InitSections which initializes all common sections and switches to
text. The new method is implemented by each platform streamer in a way
that it sees fit. So AsmParser can now do this:
void AsmParser::CheckForValidSection() {
if (!ParsingInlineAsm && !getStreamer().getCurrentSection()) {
TokError("expected section directive before assembly directive");
Out.InitToTextSection();
}
}
Which is much more reasonable.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172450 91177308-0d34-0410-b5e6-96231b3b80d8
Since it's used by extensions. One further step to fully decoupling
GenericAsmParser from an intimate knowledge of the internals of AsmParser,
pointing it to the MCASmParser interface instead (like all other parser
extensions do).
Since this change moves the MacroArgument type to the interface header, it's
renamed to be a bit more descriptive in a general context.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172449 91177308-0d34-0410-b5e6-96231b3b80d8
The methods are also exposed via the MCAsmParser interface, which allows more
than one client to control them. Previously, GenericAsmParser was playing with
a member var in AsmParser directly (by virtue of being its friend).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172440 91177308-0d34-0410-b5e6-96231b3b80d8
This was an experimental option, but needs to be defined
per-target. e.g. PPC A2 needs to aggressively hide latency.
I converted some in-order scheduling tests to A2. Hal is working on
more test cases.
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method because getContents().size() already covers it. So computeFragmentSize
can use the generic MCEncodedFragment interface when querying both Data and
Relaxable fragments for contents sizes.
No change in functionality
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171903 91177308-0d34-0410-b5e6-96231b3b80d8
utils/sort_includes.py script.
Most of these are updating the new R600 target and fixing up a few
regressions that have creeped in since the last time I sorted the
includes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171362 91177308-0d34-0410-b5e6-96231b3b80d8
MC disassembler clients (LLDB) are interested in querying if an
instruction may affect control flow other than by virtue of being
an explicit branch instruction. For example, instructions which
write directly to the PC on some architectures.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170610 91177308-0d34-0410-b5e6-96231b3b80d8
These were defined on TargetRegisterInfo, but they don't use any information
that's not available in MCRegisterInfo, so sink them down to be available
at the MC layer.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170608 91177308-0d34-0410-b5e6-96231b3b80d8
compilation directory.
This defaults to the current working directory, just as it always has,
but now an assembler can choose to override it with a custom directory.
I've taught llvm-mc about this option and added a test case.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170371 91177308-0d34-0410-b5e6-96231b3b80d8
Mips16 is really a processor decoding mode (ala thumb 1) and in the same
program, mips16 and mips32 functions can exist and can call each other.
If a jal type instruction encounters an address with the lower bit set, then
the processor switches to mips16 mode (if it is not already in it). If the
lower bit is not set, then it switches to mips32 mode.
The linker knows which functions are mips16 and which are mips32.
When relocation is performed on code labels, this lower order bit is
set if the code label is a mips16 code label.
In general this works just fine, however when creating exception handling
tables and dwarf, there are cases where you don't want this lower order
bit added in.
This has been traditionally distinguished in gas assembly source by using a
different syntax for the label.
lab1: ; this will cause the lower order bit to be added
lab2=. ; this will not cause the lower order bit to be added
In some cases, it does not matter because in dwarf and debug tables
the difference of two labels is used and in that case the lower order
bits subtract each other out.
To fix this, I have added to mcstreamer the notion of a debuglabel.
The default is for label and debug label to be the same. So calling
EmitLabel and EmitDebugLabel produce the same result.
For various reasons, there is only one set of labels that needs to be
modified for the mips exceptions to work. These are the "$eh_func_beginXXX"
labels.
Mips overrides the debug label suffix from ":" to "=." .
This initial patch fixes exceptions. More changes most likely
will be needed to DwarfCFException to make all of this work
for actual debugging. These changes will be to emit debug labels in some
places where a simple label is emitted now.
Some historical discussion on this from gcc can be found at:
http://gcc.gnu.org/ml/gcc-patches/2008-08/msg00623.htmlhttp://gcc.gnu.org/ml/gcc-patches/2008-11/msg01273.html
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for a wider range of GOT entries that can hold thread-relative offsets.
This matches the behavior of GCC, which was not documented in the PPC64 TLS
ABI. The ABI will be updated with the new code sequence.
Former sequence:
ld 9,x@got@tprel(2)
add 9,9,x@tls
New sequence:
addis 9,2,x@got@tprel@ha
ld 9,x@got@tprel@l(9)
add 9,9,x@tls
Note that a linker optimization exists to transform the new sequence into
the shorter sequence when appropriate, by replacing the addis with a nop
and modifying the base register and relocation type of the ld.
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PowerPC target. This is the last of the four models, so we now have
full TLS support.
This is mostly a straightforward extension of the general dynamic model.
I had to use an additional Chain operand to tie ADDIS_DTPREL_HA to the
register copy following ADDI_TLSLD_L; otherwise everything above the
ADDIS_DTPREL_HA appeared dead and was removed.
As before, there are new test cases to test the assembly generation, and
the relocations output during integrated assembly. The expected code
gen sequence can be read in test/CodeGen/PowerPC/tls-ld.ll.
There are a couple of things I think can be done more efficiently in the
overall TLS code, so there will likely be a clean-up patch forthcoming;
but for now I want to be sure the functionality is in place.
Bill
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Add R_ARM_NONE and R_ARM_PREL31 relocation types
to MCExpr. Both of them will be used while
generating .ARM.extab and .ARM.exidx sections.
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Given a thread-local symbol x with global-dynamic access, the generated
code to obtain x's address is:
Instruction Relocation Symbol
addis ra,r2,x@got@tlsgd@ha R_PPC64_GOT_TLSGD16_HA x
addi r3,ra,x@got@tlsgd@l R_PPC64_GOT_TLSGD16_L x
bl __tls_get_addr(x@tlsgd) R_PPC64_TLSGD x
R_PPC64_REL24 __tls_get_addr
nop
<use address in r3>
The implementation borrows from the medium code model work for introducing
special forms of ADDIS and ADDI into the DAG representation. This is made
slightly more complicated by having to introduce a call to the external
function __tls_get_addr. Using the full call machinery is overkill and,
more importantly, makes it difficult to add a special relocation. So I've
introduced another opcode GET_TLS_ADDR to represent the function call, and
surrounded it with register copies to set up the parameter and return value.
Most of the code is pretty straightforward. I ran into one peculiarity
when I introduced a new PPC opcode BL8_NOP_ELF_TLSGD, which is just like
BL8_NOP_ELF except that it takes another parameter to represent the symbol
("x" above) that requires a relocation on the call. Something in the
TblGen machinery causes BL8_NOP_ELF and BL8_NOP_ELF_TLSGD to be treated
identically during the emit phase, so this second operand was never
visited to generate relocations. This is the reason for the slightly
messy workaround in PPCMCCodeEmitter.cpp:getDirectBrEncoding().
Two new tests are included to demonstrate correct external assembly and
correct generation of relocations using the integrated assembler.
Comments welcome!
Thanks,
Bill
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169910 91177308-0d34-0410-b5e6-96231b3b80d8
InitSections is called before the MCContext is initialized it could cause
duplicate temporary symbols to be emitted later (after context initialization
resets the temporary label counter).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169785 91177308-0d34-0410-b5e6-96231b3b80d8
SmallString. This makes it possible to use the length-erased SmallVectorImpl
in the interface without imposing buffer size. Thus, the size of MCInstFragment
is back down since a preallocated 8-byte contents buffer is enough.
It would be generally a good idea to rid all the fragments of SmallString as
contents, because a vector just makes more sense.
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Before this patch, when you objdump an LLVM-compiled file, objdump tried to
decode data-in-code sections as if they were code. This patch adds the missing
Mapping Symbols, as defined by "ELF for the ARM Architecture" (ARM IHI 0044D).
Patch based on work by Greg Fitzgerald.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169609 91177308-0d34-0410-b5e6-96231b3b80d8
original change description:
change MCContext to work on the doInitialization/doFinalization model
reviewed by Evan Cheng <evan.cheng@apple.com>
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This is more consistent with other vectors in this code. In addition, I ran some
tests compiling a large program and >96% of fragments have 4 or less fixups, so
SmallVector<4> is a good optimization.
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This is for the lldb team so most of but not all of the values are
to be printed as hex with this option. Some small values like the
scale in an X86 address were requested to printed in decimal
without the leading 0x.
There may be some tweaks need to places that may still be in
decimal that they want in hex. Specially for arm. I made my best
guess. Any tweaks from here should be simple.
I also did the best I know now with help from the C++ gurus
creating the cleanest formatImm() utility function and containing
the changes. But if someone has a better idea to make something
cleaner I'm all ears and game for changing the implementation.
rdar://8109283
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on 64-bit PowerPC ELF.
The patch includes code to handle external assembly and MC output with the
integrated assembler. It intentionally does not support the "old" JIT.
For the initial-exec TLS model, the ABI requires the following to calculate
the address of external thread-local variable x:
Code sequence Relocation Symbol
ld 9,x@got@tprel(2) R_PPC64_GOT_TPREL16_DS x
add 9,9,x@tls R_PPC64_TLS x
The register 9 is arbitrary here. The linker will replace x@got@tprel
with the offset relative to the thread pointer to the generated GOT
entry for symbol x. It will replace x@tls with the thread-pointer
register (13).
The two test cases verify correct assembly output and relocation output
as just described.
PowerPC-specific selection node variants are added for the two
instructions above: LD_GOT_TPREL and ADD_TLS. These are inserted
when an initial-exec global variable is encountered by
PPCTargetLowering::LowerGlobalTLSAddress(), and later lowered to
machine instructions LDgotTPREL and ADD8TLS. LDgotTPREL is a pseudo
that uses the same LDrs support added for medium code model's LDtocL,
with a different relocation type.
The rest of the processing is straightforward.
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AKA: Recompile *ALL* the source code!
This one went much better. No manual edits here. I spot-checked for
silliness and grep-checked for really broken edits and everything seemed
good. It all still compiles. Yell if you see something that looks goofy.
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Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module
include to be the nearest plausible thing I could find. If you own or
care about any of these source files, I encourage you to take some time
and check that these edits were sensible. I can't have broken anything
(I strictly added headers, and reordered them, never removed), but they
may not be the headers you'd really like to identify as containing the
API being implemented.
Many forward declarations and missing includes were added to a header
files to allow them to parse cleanly when included first. The main
module rule does in fact have its merits. =]
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The default for 64-bit PowerPC is small code model, in which TOC entries
must be addressable using a 16-bit offset from the TOC pointer. Additionally,
only TOC entries are addressed via the TOC pointer.
With medium code model, TOC entries and data sections can all be addressed
via the TOC pointer using a 32-bit offset. Cooperation with the linker
allows 16-bit offsets to be used when these are sufficient, reducing the
number of extra instructions that need to be executed. Medium code model
also does not generate explicit TOC entries in ".section toc" for variables
that are wholly internal to the compilation unit.
Consider a load of an external 4-byte integer. With small code model, the
compiler generates:
ld 3, .LC1@toc(2)
lwz 4, 0(3)
.section .toc,"aw",@progbits
.LC1:
.tc ei[TC],ei
With medium model, it instead generates:
addis 3, 2, .LC1@toc@ha
ld 3, .LC1@toc@l(3)
lwz 4, 0(3)
.section .toc,"aw",@progbits
.LC1:
.tc ei[TC],ei
Here .LC1@toc@ha is a relocation requesting the upper 16 bits of the
32-bit offset of ei's TOC entry from the TOC base pointer. Similarly,
.LC1@toc@l is a relocation requesting the lower 16 bits. Note that if
the linker determines that ei's TOC entry is within a 16-bit offset of
the TOC base pointer, it will replace the "addis" with a "nop", and
replace the "ld" with the identical "ld" instruction from the small
code model example.
Consider next a load of a function-scope static integer. For small code
model, the compiler generates:
ld 3, .LC1@toc(2)
lwz 4, 0(3)
.section .toc,"aw",@progbits
.LC1:
.tc test_fn_static.si[TC],test_fn_static.si
.type test_fn_static.si,@object
.local test_fn_static.si
.comm test_fn_static.si,4,4
For medium code model, the compiler generates:
addis 3, 2, test_fn_static.si@toc@ha
addi 3, 3, test_fn_static.si@toc@l
lwz 4, 0(3)
.type test_fn_static.si,@object
.local test_fn_static.si
.comm test_fn_static.si,4,4
Again, the linker may replace the "addis" with a "nop", calculating only
a 16-bit offset when this is sufficient.
Note that it would be more efficient for the compiler to generate:
addis 3, 2, test_fn_static.si@toc@ha
lwz 4, test_fn_static.si@toc@l(3)
The current patch does not perform this optimization yet. This will be
addressed as a peephole optimization in a later patch.
For the moment, the default code model for 64-bit PowerPC will remain the
small code model. We plan to eventually change the default to medium code
model, which matches current upstream GCC behavior. Note that the different
code models are ABI-compatible, so code compiled with different models will
be linked and execute correctly.
I've tested the regression suite and the application/benchmark test suite in
two ways: Once with the patch as submitted here, and once with additional
logic to force medium code model as the default. The tests all compile
cleanly, with one exception. The mandel-2 application test fails due to an
unrelated ABI compatibility with passing complex numbers. It just so happens
that small code model was incredibly lucky, in that temporary values in
floating-point registers held the expected values needed by the external
library routine that was called incorrectly. My current thought is to correct
the ABI problems with _Complex before making medium code model the default,
to avoid introducing this "regression."
Here are a few comments on how the patch works, since the selection code
can be difficult to follow:
The existing logic for small code model defines three pseudo-instructions:
LDtoc for most uses, LDtocJTI for jump table addresses, and LDtocCPT for
constant pool addresses. These are expanded by SelectCodeCommon(). The
pseudo-instruction approach doesn't work for medium code model, because
we need to generate two instructions when we match the same pattern.
Instead, new logic in PPCDAGToDAGISel::Select() intercepts the TOC_ENTRY
node for medium code model, and generates an ADDIStocHA followed by either
a LDtocL or an ADDItocL. These new node types correspond naturally to
the sequences described above.
The addis/ld sequence is generated for the following cases:
* Jump table addresses
* Function addresses
* External global variables
* Tentative definitions of global variables (common linkage)
The addis/addi sequence is generated for the following cases:
* Constant pool entries
* File-scope static global variables
* Function-scope static variables
Expanding to the two-instruction sequences at select time exposes the
instructions to subsequent optimization, particularly scheduling.
The rest of the processing occurs at assembly time, in
PPCAsmPrinter::EmitInstruction. Each of the instructions is converted to
a "real" PowerPC instruction. When a TOC entry needs to be created, this
is done here in the same manner as for the existing LDtoc, LDtocJTI, and
LDtocCPT pseudo-instructions (I factored out a new routine to handle this).
I had originally thought that if a TOC entry was needed for LDtocL or
ADDItocL, it would already have been generated for the previous ADDIStocHA.
However, at higher optimization levels, the ADDIStocHA may appear in a
different block, which may be assembled textually following the block
containing the LDtocL or ADDItocL. So it is necessary to include the
possibility of creating a new TOC entry for those two instructions.
Note that for LDtocL, we generate a new form of LD called LDrs. This
allows specifying the @toc@l relocation for the offset field of the LD
instruction (i.e., the offset is replaced by a SymbolLo relocation).
When the peephole optimization described above is added, we will need
to do similar things for all immediate-form load and store operations.
The seven "mcm-n.ll" test cases are kept separate because otherwise the
intermingling of various TOC entries and so forth makes the tests fragile
and hard to understand.
The above assumes use of an external assembler. For use of the
integrated assembler, new relocations are added and used by
PPCELFObjectWriter. Testing is done with "mcm-obj.ll", which tests for
proper generation of the various relocations for the same sequences
tested with the external assembler.
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to support it. Original patch with the parsing and plumbing by the PaX team and
Roman Divacky. I added the bits in MCDwarf.cpp and the test.
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This untangles the switch cases of the old Move and RelMove opcodes a bit
and makes it clear how to add new instructions.
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Give MCCFIInstruction a single, private constructor and add helper static
methods that create each type of cfi instruction. This is is preparation
for changing its representation. The representation with a pair
MachineLocations older than MC and has been abused quiet a bit to support
more cfi instructions.
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Expose the processor resources defined by the machine model to the
scheduler and other clients through the TargetSchedule interface.
Normalize each resource count with respect to other kinds of
resources. This allows scheduling heuristics to balance resources
against other kinds of resources and latency.
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include/llvm/MC/MCTargetAsmParser.h:46:8: error: 'llvm::ParseInstructionInfo' has a field 'llvm::ParseInstructionInfo::AsmRewrites' whose type uses the anonymous namespace [-Werror]
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This patch adds initial PPC64 TOC MC object creation using the small mcmodel
(a single 64K TOC) adding the some TOC relocations (R_PPC64_TOC,
R_PPC64_TOC16, and R_PPC64_TOC16DS).
The addition of 'undefinedExplicitRelSym' hook on 'MCELFObjectTargetWriter'
is meant to avoid the creation of an unreferenced ".TOC." symbol (used in
the .odp creation) as well to set the R_PPC64_TOC relocation target as the
temporary ".TOC." symbol. On PPC64 ABI, the R_PPC64_TOC relocation should
not point to any symbol.
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and easier to read by adding a couple helper functions. Suggestion by
Chandler Carruth and seconded by Meador Inge!
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Per the October 12, 2012 Proposal for annotated disassembly output sent out by
Jim Grosbach this set of changes implements this for X86 and arm. The llvm-mc
tool now has a -mdis option to produced the marked up disassembly and a couple
of small example test cases have been added.
rdar://11764962
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a memory operand. Retain this information and then add the sizing directives
to the IR. This allows the backend to do proper instruction selection.
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*NamedDecl. In turn, build the expressions after we're finished parsing the
asm. This avoids a crasher if the lookup fails.
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layer. Add the ParseMSInlineAsm() function, which is the new interface to
clang. Also expose the new MCAsmParserSemaCallback interface, which is used
by the back-end to do name lookup in Sema. Finally, remove the now defunct
APIs introduced in r165946.
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inline assembly. For the time being, these will be called directly by clang.
However, in the near future I expect these to be sunk back into the MC layer
and more basic APIs (e.g., getClobbers(), getConstraints(), etc.) will be called
by clang.
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This patch replaces the EmitRawText by a EmitTCEntry class (specialized for
each Streamer) in PowerPC64 TOC entry creation.
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the interface between the front-end and the MC layer when parsing inline
assembly. Unfortunately, this is too deep into the parsing stack. Specifically,
we're unable to handle target-independent assembly (i.e., assembly directives,
labels, etc.). Note the MatchAndEmitInstruction() isn't the correct
abstraction either. I'll be exposing target-independent hooks shortly, so this
is really just a cleanup.
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isa<> et al. automatically infer when the cast is an upcast (including a
self-cast), so these are no longer necessary.
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of operand is specific to MS-style inline assembly and should not be generated
when parsing normal assembly.
The purpose of the wildcard operands are to allow the AsmParser to match
multiple instructions (i.e., MCInsts) to a given ms-style asm statement. For
the time being the matcher just returns the first match. This patch only
implements wildcard matches for memory operands. Support for register
wildcards will be added in the near future.
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map constraints and MCInst operands to inline asm operands. This replaces the
getMCInstOperandNum() function.
The logic to determine the constraints are not in place, so we still default to
a register constraint (i.e., "r"). Also, we no longer build the MCInst but
rather return just the opcode to get the MCInstrDesc.
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The target backend can support data-in-code load commands even when
the assembler doesn't, or vice-versa. Allow targets to opt-in for
direct-to-object.
PR13973.
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Reduces runtime of i386-large-relocations.s by 10x in Release builds, even more
in Debug+Asserts builds.
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to improve compatibility with GNU as.
Based on a patch by PaX Team.
Fixed assertion failures on non-Darwin and added additional test cases.
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Now where we used to call ReInitMCSubtargetInfo, we actually recompute
the same information as InitMCSubtargetInfo instead of only setting
the feature bits.
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* wrap code blocks in \code ... \endcode;
* refer to parameter names in paragraphs correctly (\arg is not what most
people want -- it starts a new paragraph);
* use \param instead of \arg to document parameters in order to be consistent
with the rest of the codebase.
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.set a, b - c + CONSTANT
d = b - c + CONSTANT
Both 'a' and 'd' should be marked as absolute symbols (N_ABS).
rdar://12219394
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Apparently, NumSubRegIndices was completely unused before. Adjust it by
one to include the null subreg index, just like getNumRegs() includes
the null register.
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For some reason .lcomm uses byte alignment and .comm log2 alignment so we can't
use the same setting for both. Fix this by reintroducing the LCOMM enum.
I verified this against mingw's gcc.
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- Darwin lied about not supporting .lcomm and turned it into zerofill in the
asm parser. Push the zerofill-conversion down into macho-specific code.
- This makes the tri-state LCOMMType enum superfluous, there are no targets
without .lcomm.
- Do proper error reporting when trying to use .lcomm with alignment on a target
that doesn't support it.
- .comm and .lcomm alignment was parsed in bytes on COFF, should be power of 2.
- Fixes PR13755 (.lcomm crashes on ELF).
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the NumMCOperands argument to the GetMCInstOperandNum() function that is set
to the number of MCOperands this asm operand mapped to.
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MatchInstructionImpl() function.
These values are used by the ConvertToMCInst() function to index into the
ConversionTable. The values are also needed to call the GetMCInstOperandNum()
function.
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The MCInst is immediately passed to the copy-constructor for local
storage, so there's no need for the parameter itself to be by-value.
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within the codegen EK_GPRel64BlockAddress. This was not
supported for direct object output and resulted in an assertion.
This change adds support for EK_GPRel64BlockAddress for
direct object.
One fallout from this is to turn on rela relocations
for mips64 to match gas.
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this is the index of the operand that failed to match.
Note: This may cause a buildbot failure due to an API mismatch in clang. Should
recover with my next commit to clang.
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Select instructions pick one of two virtual registers based on a
condition, like x86 cmov. On targets like ARM that support predication,
selects can sometimes be eliminated by predicating the instruction
defining one of the operands.
Teach PeepholeOptimizer to recognize select instructions, and ask the
target to optimize them.
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Refactor the TableGen'erated fixed length disassemblmer to use a
table-driven state machine rather than a massive set of nested
switch() statements.
As a result, the ARM Disassembler (ARMDisassembler.cpp) builds much more
quickly and generates a smaller end result. For a Release+Asserts build on
a 16GB 3.4GHz i7 iMac w/ SSD:
Time to compile at -O2 (averaged w/ hot caches):
Previous: 35.5s
New: 8.9s
TEXT size:
Previous: 447,251
New: 297,661
Builds in 25% of the time previously required and generates code 66% of
the size.
Execution time of the disassembler is only slightly slower (7% disassembling
10 million ARM instructions, 19.6s vs 21.0s). The new implementation has
not yet been tuned, however, so the performance should almost certainly
be recoverable should it become a concern.
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This new API will be used by clang to parse ms-style inline asms.
One goal of this project is to use this style of inline asm for targets other
then x86. Therefore, this API needs to be implemented for non-x86 targets at
some point in the future.
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This replaces an existing subtarget hook on ARM and allows standard
CodeGen passes to potentially use the property.
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These tables were indexed by [register][subreg index] which made them,
very large and sparse.
Replace them with lists of sub-register indexes that match the existing
lists of sub-registers. MCRI::getSubReg() becomes a very short linear
search, like getSubRegIndex() already was.
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subtarget CPU descriptions and support new features of
MachineScheduler.
MachineModel has three categories of data:
1) Basic properties for coarse grained instruction cost model.
2) Scheduler Read/Write resources for simple per-opcode and operand cost model (TBD).
3) Instruction itineraties for detailed per-cycle reservation tables.
These will all live side-by-side. Any subtarget can use any
combination of them. Instruction itineraries will not change in the
near term. In the long run, I expect them to only be relevant for
in-order VLIW machines that have complex contraints and require a
precise scheduling/bundling model. Once itineraries are only actively
used by VLIW-ish targets, they could be replaced by something more
appropriate for those targets.
This tablegen backend rewrite sets things up for introducing
MachineModel type #2: per opcode/operand cost model.
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The TargetInstrInfo::getNumMicroOps API does not change, but soon it
will be used by MachineScheduler. Now each subtarget can specify the
number of micro-ops per itinerary class. For ARM, this is currently
always dynamic (-1), because it is used for load/store multiple which
depends on the number of register operands.
Zero is now a valid number of micro-ops. This can be used for
nop pseudo-instructions or instructions that the hardware can squash
during dispatch.
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which many Mips 64 ABIs use than for O64 which many
if not all other target ABIs use.
Most architectures have the following 64 bit relocation record format:
typedef struct
{
Elf64_Addr r_offset; /* Address of reference */
Elf64_Xword r_info; /* Symbol index and type of relocation */
} Elf64_Rel;
typedef struct
{
Elf64_Addr r_offset;
Elf64_Xword r_info;
Elf64_Sxword r_addend;
} Elf64_Rela;
Whereas N64 has the following format:
typedef struct
{
Elf64_Addr r_offset;/* Address of reference */
Elf64_Word r_sym; /* Symbol index */
Elf64_Byte r_ssym; /* Special symbol */
Elf64_Byte r_type3; /* Relocation type */
Elf64_Byte r_type2; /* Relocation type */
Elf64_Byte r_type; /* Relocation type */
} Elf64_Rel;
typedef struct
{
Elf64_Addr r_offset;/* Address of reference */
Elf64_Word r_sym; /* Symbol index */
Elf64_Byte r_ssym; /* Special symbol */
Elf64_Byte r_type3; /* Relocation type */
Elf64_Byte r_type2; /* Relocation type */
Elf64_Byte r_type; /* Relocation type */
Elf64_Sxword r_addend;
} Elf64_Rela;
The structure is the same size, but the r_info data element
is now 5 separate elements. Besides the content aspects,
endian byte reordering will be different for the area with
each element being endianized separately.
I treat this as generic and continue to pass r_type as
an integer masking and unmasking the byte sized N64
values for N64 mode. I've implemented this and it causes no
affect on other current targets.
This passes make check.
Jack
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Original commit message:
Allow up to 64 functional units per processor itinerary.
This patch changes the type used to hold the FU bitset from unsigned to uint64_t.
This will be needed for some upcoming PowerPC itineraries.
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This patch changes the type used to hold the FU bitset from unsigned to uint64_t.
This will be needed for some upcoming PowerPC itineraries.
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This fixes an accidental dependence on static initialization order that I introduced yesterday.
Thank you Lang!!!
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This allows a subtarget to explicitly specify the issue width and
other properties without providing pipeline stage details for every
instruction.
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These functions exposed the layout of the underlying data tables as
null-terminated uint16_t arrays.
Use the new MCSubRegIterator, MCSuperRegIterator, and MCRegAliasIterator
classes instead.
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No functional change intended.
Sorry for the churn. The iterator classes are supposed to help avoid
giant commits like this one in the future. The TableGen-produced
register lists are getting quite large, and it may be necessary to
change the table representation.
This makes it possible to do so without changing all clients (again).
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Each register unit has one or two root registers. The full set of
registers containing a given register unit can be computed as the union
of the root registers and their super-registers.
Provide an MCRegUnitRootIterator class to enumerate the roots.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157753 91177308-0d34-0410-b5e6-96231b3b80d8
Also add subclasses MCSubRegIterator, MCSuperRegIterator, and
MCRegAliasIterator.
These iterators provide an abstract interface to the MCRegisterInfo
register lists so the internal representation can be changed without
changing all clients.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157695 91177308-0d34-0410-b5e6-96231b3b80d8
Register units are already used internally in TableGen to compute
register pressure sets and overlapping registers. This patch makes them
available to the code generators.
The register unit lists are differentially encoded so they can be reused
for many related registers. This keeps the total size of the lists below
200 bytes for most targets. ARM has the largest table at 560 bytes.
Add an MCRegUnitIterator for traversing the register unit lists. It
provides an abstract interface so the representation can be changed in
the future without changing all clients.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157650 91177308-0d34-0410-b5e6-96231b3b80d8
