We now (1) correctly decode the branch immediate, (2) modify the immediate to
corretly treat it as PC-rel, and (3) properly populate the stub entry.
Previously we had been doing each of these wrong.
<rdar://problem/17750739>
llvm-svn: 214285
use in -verify mode.
This patch adds three hidden command line options to llvm-rtdyld:
-target-addr-start <start-addr> : Specify the start of the virtual address
space on the phony target.
-target-addr-end <end-addr> : Specify the end of the virtual address space
on the phony target.
-target-section-sep <sep> : Specify the separation (in bytes) between the
end of one section and the start of the next.
These options automatically default to sane values for the target platform. In
particular, they allow narrow (e.g. 32-bit, 16-bit) targets to be tested from
wider (e.g. 64-bit, 32-bit) hosts without overflowing pointers.
The section separation option defaults to zero, but can be set to a large number
(e.g. 1 << 32) to force large separations between sections in order to
stress-test large-code-model code.
llvm-svn: 214255
full paths for its first argument.
This allows us to remove the annoying sed lines in the test cases, and write
direct references to file names in stub_addr calls (rather than <filename>
placeholders).
llvm-svn: 214211
Having both Triple::arm64 and Triple::aarch64 is extremely confusing, and
invites bugs where only one is checked. In reality, the only legitimate
difference between the two (arm64 usually means iOS) is also present in the OS
part of the triple and that's what should be checked.
We still parse the "arm64" triple, just canonicalise it to Triple::aarch64, so
there aren't any LLVM-side test changes.
llvm-svn: 213743
There's no reason to restrict this particular piece of RuntimeDyldChecker
functionality to +Asserts builds.
This should fix failures in MachO_x86-64_PIC_relocations.s on release bots.
llvm-svn: 213708
RuntimeDyldChecker had been testing isalpha(Expr[0]) to recognise symbol tokens,
and throwing unrecognized token errors when it hit symbols with leading
underscores. This fixes that.
llvm-svn: 213706
This patch introduces a 'stub_addr' builtin that can be used to find the address
of the stub for a given (<file>, <section>, <symbol>) tuple. This address can be
used both to verify the contents of stubs (by loading from the returned address)
and to verify references to stubs (by comparing against the returned address).
Example (1) - Verifying stub contents:
Load 8 bytes (assuming a 64-bit target) from the stub for 'x' in the __text
section of f.o, and compare that value against the addres of 'x'.
# rtdyld-check: *{8}(stub_addr(f.o, __text, x) = x
Example (2) - Verifying references to stubs:
Decode the immediate of the instruction at label 'l', and verify that it's
equal to the offset from the next instruction's PC to the stub for 'y' in the
__text section of f.o (i.e. it's the correct PC-rel difference).
# rtdyld-check: decode_operand(l, 4) = stub_addr(f.o, __text, y) - next_pc(l)
l:
movq y@GOTPCREL(%rip), %rax
Since stub inspection requires cooperation with RuntimeDyldImpl this patch
pimpl-ifies RuntimeDyldChecker. Its implementation is moved in to a new class,
RuntimeDyldCheckerImpl, that has access to the definition of RuntimeDyldImpl.
llvm-svn: 213698
Factor out the addend encoding into a helper function and simplify the
processRelocationRef.
Also add a few simple rtdyld tests. More tests to come once GOTs can be tested too.
Related to <rdar://problem/17768539>
llvm-svn: 213689
In MachO for AArch64 it is possible to have an explicit addend defined by
the ARM64_RELOC_ADDEND relocation or having an addend encoded within the
instruction. Only one of them are allowed per relocation.
llvm-svn: 213687
This patch enables the new ELFv2 ABI in the runtime dynamic loader.
The loader has to implement the following features:
- In the ELFv2 ABI, do not look up a function descriptor in .opd, but
instead use the local entry point when resolving a direct call.
- Update the TOC restore code to use the new TOC slot linkage area
offset.
- Create PLT stubs appropriate for the ELFv2 ABI.
Note that this patch also adds common-code changes. These are necessary
because the loader must check the newly added ELF flags: the e_flags
header bits encoding the ABI version, and the st_other symbol table
entry bits encoding the local entry point offset. There is currently
no way to access these, so I've added ObjectFile::getPlatformFlags and
SymbolRef::getOther accessors.
Reviewed by Hal Finkel.
llvm-svn: 213491
getBasicRelocationEntry to use this rather than 'memcpy' to get the
relocation addend. Targets with non-trivial addend encodings (E.g. AArch64) can
override decodeAddend to handle immediates with interesting encodings.
No functional change.
llvm-svn: 213435
RelocationEntry.
No test case yet, as this primarily hits GOT entries, which RuntimeDyldChecker
can't examine yet. I'm actively working on features that will enable us to
test this.
llvm-svn: 213408
relaxed in the big RuntimeDyldMachO cleanup of r213293.
No test case yet - this was found via inspection and there's no easy way to test
GOT alignment in RuntimeDyldChecker at the moment. I'm working on adding support
for this now, and hope to have a test case for this soon.
llvm-svn: 213331
The previous implementation of RuntimeDyldMachO mixed logic for all targets
within a single class, creating problems for readability, maintainability, and
performance. To address these issues, this patch strips the RuntimeDyldMachO
class down to just target-independent functionality, and moves all
target-specific functionality into target-specific subclasses RuntimeDyldMachO.
The new class hierarchy is as follows:
class RuntimeDyldMachO
Implemented in RuntimeDyldMachO.{h,cpp}
Contains logic that is completely independent of the target. This consists
mostly of MachO helper utilities which the derived classes use to get their
work done.
template <typename Impl>
class RuntimeDyldMachOCRTPBase<Impl> : public RuntimeDyldMachO
Implemented in RuntimeDyldMachO.h
Contains generic MachO algorithms/data structures that defer to the Impl class
for target-specific behaviors.
RuntimeDyldMachOARM : public RuntimeDyldMachOCRTPBase<RuntimeDyldMachOARM>
RuntimeDyldMachOARM64 : public RuntimeDyldMachOCRTPBase<RuntimeDyldMachOARM64>
RuntimeDyldMachOI386 : public RuntimeDyldMachOCRTPBase<RuntimeDyldMachOI386>
RuntimeDyldMachOX86_64 : public RuntimeDyldMachOCRTPBase<RuntimeDyldMachOX86_64>
Implemented in their respective *.h files in lib/ExecutionEngine/RuntimeDyld/MachOTargets
Each of these contains the relocation logic specific to their target architecture.
llvm-svn: 213293
The registration scheme used in r211652 violated the read-only contract of
MemoryBuffer. This caused crashes in llvm-rtdyld where macho objects were backed
by read-only mmap'd memory.
llvm-svn: 213086
reading MachO files magic numbers in RuntimeDyld.
This is required now that we're testing cross-platform JITing (via
RuntimeDyldChecker), and should fix some issues that David Fang has seen on PPC
builds.
llvm-svn: 213012
The compiler often emits assembler-local labels (beginning with 'L') for use in
relocation expressions, however these aren't included in the object files.
Teach RuntimeDyldChecker to warn the user if they try to use one of these in an
expression, since it will never work.
llvm-svn: 212777
This patch adds a "-verify" mode to the llvm-rtdyld utility. In verify mode,
llvm-rtdyld will test supplied expressions against the linked program images
that it creates in memory. This scheme can be used to verify the correctness
of the relocation logic applied by RuntimeDyld.
The expressions to test will be read out of files passed via the -check option
(there may be more than one of these). Expressions to check are extracted from
lines of the form:
# rtdyld-check: <expression>
This system is designed to fit the llvm-lit regression test workflow. It is
format and target agnostic, and supports verification of images linked for
remote targets. The expression language is defined in
llvm/include/llvm/RuntimeDyldChecker.h . Examples can be found in
test/ExecutionEngine/RuntimeDyld.
llvm-svn: 211956
Current PPC64 RuntimeDyld code to handle TOC relocations has two
problems:
- With recent linkers, in addition to the relocations that implicitly
refer to the TOC base (R_PPC64_TOC*), you can now also use the .TOC.
magic symbol with any other relocation to refer to the TOC base
explicitly. This isn't currently used much in ELFv1 code (although
it could be), but it is essential in ELFv2 code.
- In a complex JIT environment with multiple modules, each module may
have its own .toc section, and TOC relocations in one module must
refer to *its own* TOC section. The current findPPC64TOC implementation
does not correctly implement this; in fact, it will always return the
address of the first TOC section it finds anywhere. (Note that at the
time findPPC64TOC is called, we don't even *know* which module the
relocation originally resided in, so it is not even possible to fix
this routine as-is.)
This commit fixes both problems by handling TOC relocations earlier, in
processRelocationRef. To do this, I've removed the findPPC64TOC routine
and replaced it by a new routine findPPC64TOCSection, which works
analogously to findOPDEntrySection in scanning the sections of the
ObjImage provided by its caller, processRelocationRef. This solves the
issue of finding the correct TOC section associated with the current
module.
This makes it straightforward to implement both R_PPC64_TOC relocations,
and relocations explicitly refering to the .TOC. symbol, directly in
processRelocationRef. There is now a new problem in implementing the
R_PPC64_TOC16* relocations, because those can now in theory involve
*three* different sections: the relocation may be applied in section A,
refer explicitly to a symbol in section B, and refer implicitly to the
TOC section C. The final processing of the relocation thus may only
happen after all three of these sections have been assigned final
addresses. There is currently no obvious means to implement this in
its general form with the common-code RuntimeDyld infrastructure.
Fortunately, ppc64 code usually makes no use of this most general form;
in fact, TOC16 relocations are only ever generated by LLVM for symbols
residing themselves in the TOC, which means "section B" == "section C"
in the above terminology. This special case can easily be handled with
the current infrastructure, and that is what this patch does.
[ Unhandled cases result in an explicit error, unlike the current code
which silently returns the wrong TOC base address ... ]
This patch makes the JIT work on both BE and LE (ELFv2 requires
additional patches, of course), and allowed me to successfully run
complex JIT scenarios (via mesa/llvmpipe).
Reviewed by Hal Finkel.
llvm-svn: 211885
This makes the buffer ownership on error conditions very natural. The buffer
is only moved out of the argument if an object is constructed that now
owns the buffer.
llvm-svn: 211546
When RuntimeDyldELF creates stub functions, it needs to install
relocations that will resolve to the final address of the target
routine. Since those are 16-bit relocs, they need to be applied to the
least-significant halfword of the instruction. On big-endian ppc64,
this means that addresses have to be adjusted by 2, which is what the
code currently does.
However, on a little-endian system, the address must *not* be adjusted;
the least-significant halfword is the first one. This patch updates the
RuntimeDyldELF code to take the target byte order into account.
llvm-svn: 211384
This adds support for several missing PPC64 relocations in the
straight-forward manner to RuntimeDyldELF.cpp.
Note that this actually fixes a failure of a large-model test case on
PowerPC, allowing the XFAIL to be removed.
llvm-svn: 211382
This commit starts with a "git mv ARM64 AArch64" and continues out
from there, renaming the C++ classes, intrinsics, and other
target-local objects for consistency.
"ARM64" test directories are also moved, and tests that began their
life in ARM64 use an arm64 triple, those from AArch64 use an aarch64
triple. Both should be equivalent though.
This finishes the AArch64 merge, and everyone should feel free to
continue committing as normal now.
llvm-svn: 209577
Rafael Espindola