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.

llvm-svn: 108568

thus is a much more meaningful name.

llvm-svn: 108563

TII::isMoveInstr is going tobe completely removed.

llvm-svn: 108507

follow on to r103765

llvm-svn: 108390

will still be stripped by the linker when it generates the final image.

llvm-svn: 107440

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.

llvm-svn: 107433

llvm-svn: 107215

llvm-svn: 107214

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".

llvm-svn: 107205

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();
  }

llvm-svn: 106285

llvm-svn: 106073

llvm-svn: 105379

as well.

llvm-svn: 104642

and testcases accordingly.

llvm-svn: 104635

llvm-svn: 104414

llvm-svn: 104197

llvm-svn: 103586

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.

llvm-svn: 103568

llvm-svn: 103272

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.

llvm-svn: 103140

preventing the emission of the NOP on Darwin for a
function with no actual code.  From timberwolfmc
with TEST=optllcdbg.

llvm-svn: 102843

	##DEBUG_VALUE: runOnMachineFunction:this <- RDI+0
	##DEBUG_VALUE: runOnMachineFunction:fn <- RSI+0
	##DEBUG_VALUE: DeadDefs <- undef ## SimpleRegisterCoalescing.cpp:2706
	##DEBUG_VALUE: getRegInfo:this <- [%rsp+$56]+$0
	##DEBUG_VALUE: getTarget:this <- [%rsp+$56]+$0

llvm-svn: 102655

alignment of globals to the preferred alignment, but only when
there is no section specified on the global (by far the common
case).

llvm-svn: 102515

llvm-svn: 102486

ForcedAlignBits argument, tweaking the single client of it.

llvm-svn: 102484

llvm-svn: 102483

llvm-svn: 102453

should fix some "g++.dg-struct-layout-1" failures, 
rdar://7886017

llvm-svn: 102421

llvm-svn: 102401

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

llvm-svn: 102400

alignment of globals with a specified alignment, we fix
common variables to obey their alignment.  Add a comment
explaining why this behavior is important.

llvm-svn: 102365

llvm-svn: 102359

preferred alignment unless they were common or some other special
case.

llvm-svn: 102300

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.

llvm-svn: 101879

llvm-svn: 101640

llvm-svn: 101575

merge XCore's section into MCSectionELF

llvm-svn: 100812

llvm-svn: 100709

llvm-svn: 100700

llvm-svn: 100638