void foo() { __builtin_unreachable(); }
It will output the following on Darwin X86:
_func1:
Leh_func_begin0:
pushq %rbp
Ltmp0:
movq %rsp, %rbp
Ltmp1:
Leh_func_end0:
This prolog adds a new Call Frame Information (CFI) row to the FDE with an
address that is not within the address range of the code it describes -- part is
equal to the end of the function -- and therefore results in an invalid EH
frame. If we emit a nop in this situation, then the CFI row is now within the
address range.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108568 91177308-0d34-0410-b5e6-96231b3b80d8
Objective-C metadata types which should be marked as "weak", but which the
linker will remove upon final linkage. However, this linkage isn't specific to
Objective-C.
For example, the "objc_msgSend_fixup_alloc" symbol is defined like this:
.globl l_objc_msgSend_fixup_alloc
.weak_definition l_objc_msgSend_fixup_alloc
.section __DATA, __objc_msgrefs, coalesced
.align 3
l_objc_msgSend_fixup_alloc:
.quad _objc_msgSend_fixup
.quad L_OBJC_METH_VAR_NAME_1
This is different from the "linker_private" linkage type, because it can't have
the metadata defined with ".weak_definition".
Currently only supported on Darwin platforms.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107433 91177308-0d34-0410-b5e6-96231b3b80d8
metadata types which should be marked as "weak", but which the linker will
remove upon final linkage. For example, the "objc_msgSend_fixup_alloc" symbol is
defined like this:
.globl l_objc_msgSend_fixup_alloc
.weak_definition l_objc_msgSend_fixup_alloc
.section __DATA, __objc_msgrefs, coalesced
.align 3
l_objc_msgSend_fixup_alloc:
.quad _objc_msgSend_fixup
.quad L_OBJC_METH_VAR_NAME_1
This is different from the "linker_private" linkage type, because it can't have
the metadata defined with ".weak_definition".
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107205 91177308-0d34-0410-b5e6-96231b3b80d8
switch from this:
if (TimePassesIsEnabled) {
NamedRegionTimer T(Name, GroupName);
do_something();
} else {
do_something(); // duplicate the code, this time without a timer!
}
to this:
{
NamedRegionTimer T(Name, GroupName, TimePassesIsEnabled);
do_something();
}
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106285 91177308-0d34-0410-b5e6-96231b3b80d8
Now, the .linkonce directive is emitted as part of MCSectionCOFF::PrintSwitchToSection instead of AsmPrinter::EmitLinkage since it is an attribute of the section the symbol was placed into not the symbol itself.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103568 91177308-0d34-0410-b5e6-96231b3b80d8
Users can write broken code that emits the same label twice with asm renaming,
detect this and emit a fatal backend error instead of aborting.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103140 91177308-0d34-0410-b5e6-96231b3b80d8
preventing the emission of the NOP on Darwin for a
function with no actual code. From timberwolfmc
with TEST=optllcdbg.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102843 91177308-0d34-0410-b5e6-96231b3b80d8
alignment of globals to the preferred alignment, but only when
there is no section specified on the global (by far the common
case).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102515 91177308-0d34-0410-b5e6-96231b3b80d8
otherwise labels get incorrectly merged. We handled this by emitting a
".byte 0", but this isn't correct on thumb/arm targets where the text segment
needs to be a multiple of 2/4 bytes. Handle this by emitting a noop. This
is more gross than it should be because arm/ppc are not fully mc'ized yet.
This fixes rdar://7908505
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102400 91177308-0d34-0410-b5e6-96231b3b80d8
alignment of globals with a specified alignment, we fix
common variables to obey their alignment. Add a comment
explaining why this behavior is important.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102365 91177308-0d34-0410-b5e6-96231b3b80d8
in other types. fix this by only bumping zero-byte globals
up to a single byte if the *entire global* is zero size,
fixing PR6340.
This also fixes empty arrays etc to be handled correctly,
and only does this on subsection-via-symbols targets (aka
darwin) which is the only place where this matters.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101879 91177308-0d34-0410-b5e6-96231b3b80d8