Summary:
If none of the input files are ELF object files (for example, when
generating an object file from a single binary input file via
"-b binary"), use a fallback value for the ELF header flags instead
of crashing with an assertion failure.
Reviewers: MaskRay, ruiu, espindola
Reviewed By: MaskRay, ruiu
Subscribers: kevans, grimar, emaste, arichardson, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, kito-cheng, shiva0217, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, psnobl, benna, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, llvm-commits, jrtc27
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71101
As discussed in PR44330:
https://bugs.llvm.org/show_bug.cgi?id=44330
...the transform from pow(X, -0.5) libcall/intrinsic to
reciprocal square root can result in small deviations from
the expected result due to differences in the pow()
implementation and/or the extra rounding step from the division.
This patch proposes to allow that difference with either the
'approximate functions' or 'reassociate' FMF:
http://llvm.org/docs/LangRef.html#fast-math-flags
In practice, this likely means that the code is compiled with
all of 'fast' (-ffast-math), but I have preserved the existing
specializations for -0.0/-INF that enable generating safe code
if those special values are allowed simultaneously with
allowing approximation/reassociation.
The question about whether a similar restriction is needed for
the non-reciprocal case -- pow(X, 0.5) -- is deferred. That
transform is allowed without FMF currently, and this patch does
not change that behavior.
Differential Revision: https://reviews.llvm.org/D71706
Their naming is misleading as they only return the
ClangASTContext-owned variables. For ClangASTContext instances constructed
for a given clang::ASTContext they silently generated duplicated instances
(e.g., a second IdentifierTable) that were essentially unusable.
This removes all these getters as they are anyway not very useful in comparison
to just calling the clang::ASTContext getters. The initialization
code has been moved to the CreateASTContext initialization method so that all
code for making our own clang::ASTContext is in one place.
This avoids unneeded copies when using a range-based for loops.
This avoids new warnings due to D68912 adds -Wrange-loop-analysis to -Wall.
Differential Revision: https://reviews.llvm.org/D70869
D71372 introduced: `Unwind/thread-step-out-ret-addr-check.test` failing on
Fedora 30 Linux x86_64.
[lldb] Add additional validation on return address in 'thread step-out'
https://reviews.llvm.org/D71372
One problem is the underscored `_nonstandard_stub` in the `.s` file but not in
the LLDB command:
(lldb) breakpoint set -n nonstandard_stub
Breakpoint 1: no locations (pending).
WARNING: Unable to resolve breakpoint to any actual locations.
(lldb) process launch
Process 21919 exited with status = 0 (0x00000000)
Process 21919 launched: '/home/jkratoch/redhat/llvm-monorepo-clangassert/tools/lldb/test/Unwind/Output/thread-step-out-ret-addr-check.test.tmp' (x86_64)
(lldb) thread step-out
error: invalid thread
(lldb) _
Another problem is that Fedora Linux has executable stack by default and all
programs indicate non-executable stack by `PT_GNU_STACK`, after fixing the
underscore I was getting:
(lldb) thread step-out
Process 22294 exited with status = 0 (0x00000000)
(lldb) _
A different approach was tried as:
[lldb] Refactor thread-step-out-ret-addr-check test to use .data instead of stack variable
https://reviews.llvm.org/D71789
Differential revision: https://reviews.llvm.org/D71784
echo -e '#include <unistd.h>\nint main(void){\nsync();return 0;}'|./bin/clang -g -x c -;./bin/lldb -o 'file ./a.out' -o 'b main' -o r -o 'p (void)sync()'
Actual:
error: Expression can't be run, because there is no JIT compiled function
Expected:
<nothing, sync() has been executed>
This patch has been checked by:
D71707: clang-tidy: new bugprone-pointer-cast-widening
https://reviews.llvm.org/D71707
Casting from 32-bit `void *` to `uint64_t` requires an intermediate `uintptr_t` cast otherwise the pointer gets sign-extended:
echo -e '#include <stdio.h>\n#include <stdint.h>\nint main(void){void *p=(void *)0x80000000;unsigned long long ull=(unsigned long long)p;unsigned long long ull2=(unsigned long
long)(uintptr_t)p;printf("p=%p ull=0x%llx ull2=0x%llx\\n",p,ull,ull2);return 0;}'|gcc -Wall -m32 -x c -;./a.out
<stdin>: In function ‘main’:
<stdin>:3:66: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
p=0x80000000 ull=0xffffffff80000000 ull2=0x80000000
With debug output:
Actual:
IRMemoryMap::WriteMemory (0xb6ff8640, 0xffffffffb6f82158, 0x112) went to [0xb6ff8640..0xb6ff86b3)
Code can be run in the target.
Found function, has local address 0xffffffffb6f84000 and remote address 0xffffffffffffffff
Couldn't disassemble function : Couldn't find code range for function _Z12$__lldb_exprPv
Sections:
[0xb6f84000+0x3c]->0xb6ff9020 (alignment 4, section ID 0, name .text)
...
HandleCommand, command did not succeed
error: Expression can't be run, because there is no JIT compiled function
Expected:
IRMemoryMap::WriteMemory (0xb6ff8640, 0xb6faa15c, 0x128) went to [0xb6ff8640..0xb6ff86c3)
IRExecutionUnit::GetRemoteAddressForLocal() found 0xb6fac000 in [0xb6fac000..0xb6fac040], and returned 0xb6ff9020 from [0xb6ff9020..0xb6ff9060].
Code can be run in the target.
Found function, has local address 0xb6fac000 and remote address 0xb6ff9020
Function's code range is [0xb6ff9020+0x40]
...
Function data has contents:
0xb6ff9020: 10 4c 2d e9 08 b0 8d e2 08 d0 4d e2 00 40 a0 e1
...
Function disassembly:
0xb6ff9020: 0xe92d4c10 push {r4, r10, r11, lr}
Differential revision: https://reviews.llvm.org/D71498
This seems to have been relying on extra spills being inserted in
these blocks to increase the code size to trigger branch
relaxation. This broke when these spills were avoided. Add some asm to
pad the size of the blocks to make it not matter.
Confusingly, the intrinsic operands do not match the
instruction/custom node. The order is shuffled, and the 3rd operand is
an immediate to select operands.
I'm not 100% sure I did this right, but fdiv still doesn't select end
to end and it will be easier to tell when it does. This at least
avoids an assertion in RegBankSelect and allows hitting the fallback
on selection.
> A macro is executed as if the macro body were pasted in place of the
> calling statement. This has the consequence that a return() in a macro
> body does not just terminate execution of the macro
After converting from a function() to a macro(), the return() became
invalid. This modifies the control flow to elude the return.
Recently there has been some discussion about how we deal with optional
dependencies in LLDB. The approach in LLVM is to make things work out of
the box. If the dependency isn't there, we move on silently.
That's not true for LLDB. Unless you explicitly disable the dependency
with LLDB_ENABLE_*, you'll get a configuration-time error. The
historical reason for this is that LLDB's dependencies have a much
broader impact, think about Python for example which is required to run
the test suite.
The current approach can be frustrating from a user experience
perspective. Sometimes you just want to ensure LLDB builds with a change
in clang.
This patch changes the optional dependencies (with the exception of
Python) to a new scheme. The LLDB_ENABLE_* now takes three values: On,
Off or Auto, with the latter being the default. On and Off behave the
same as today, forcing the dependency to be enabled or disabled. If the
dependency is set to On but is not found, it results in a configuration
time warning. For Auto we detect if the dependency is there and either
enable or disable it depending on whether it's found.
Differential revision: https://reviews.llvm.org/D71306
PS: The reason Python isn't included yet is because it's so pervasive
that I plan on doing that in a separate patch.
Having this function be recursive could use up way too much stack space.
Rewrite it as an iterative traversal in the tree instead to prevent this.
Fixes PR44344.
It isn't necessary to create DIEs for all of the declaration subprograms
in a CU's retainedTypes list. We can defer creating these subprograms
until we need to prepare a call site tag that refers to one.
This cleanup was mentioned in passing in D70350.
This allows a call site tag in CU A to reference a callee DIE in CU B
without resorting to creating an incomplete duplicate DIE for the callee
inside of CU A.
We already allow cross-CU references of subprogram declarations, so it
doesn't seem like definitions ought to be special.
This improves entry value evaluation and tail call frame synthesis in
the LTO setting. During LTO, it's common for cross-module inlining to
produce a call in some CU A where the callee resides in a different CU,
and there is no declaration subprogram for the callee anywhere. In this
case llvm would (unnecessarily, I think) emit an empty DW_TAG_subprogram
in order to fill in the call site tag. That empty 'definition' defeats
entry value evaluation etc., because the debugger can't figure out what
it means.
As a follow-up, maybe we could add a DWARF verifier check that a
DW_TAG_subprogram at least has a DW_AT_name attribute.
Update:
Reland with a fix to create a declaration DIE when the declaration is
missing from the CU's retainedTypes list. The declaration is left out
of the retainedTypes list in two cases:
1) Re-compiling pre-r266445 bitcode (in which declarations weren't added
to the retainedTypes list), and
2) Doing LTO function importing (which doesn't update the retainedTypes
list).
It's possible to handle (1) and (2) by modifying the retainedTypes list
(in AutoUpgrade, or in the LTO importing logic resp.), but I don't see
an advantage to doing it this way, as it would cause more DWARF to be
emitted compared to creating the declaration DIEs lazily.
Tested with a stage2 ThinLTO+RelWithDebInfo build of clang, and with a
ReleaseLTO-g build of the test suite.
rdar://46577651, rdar://57855316, rdar://57840415
Differential Revision: https://reviews.llvm.org/D70350
Summary:
llvm-objdump will commonly error out when disassembling a Mach-O binary with
stab symbols, or when printing a Mach-O symbol table that includesstab symbols.
That is because the Mach-O N_OSO symbol has been modified to include the
bottom 8-bit value of the Mach-O's cpusubtype value in the section field. In
general, one cannot blindly assume a stab symbol's section field is valid
unless one has actually consulted the specification for the specific stab.
Since objdump mostly just walks the symbol table to get mnemonics for code
disassembly it's best for objdump to just ignore stab symbols. llvm-nm will
do a more complete and correct job of displaying Mach-O symbol table contents.
Reviewers: pete, lhames, ab, thegameg, jhenderson, MaskRay
Reviewed By: thegameg, MaskRay
Subscribers: MaskRay, rupprecht, seiya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71394
