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
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
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
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
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
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
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
"Print" methods to "Emit". Emit is something that goes
to an mc streamer, Print is something that goes to a
raw_ostream (for inline asm)
llvm-svn: 100337
"asm printering" happens through MCStreamer. This also
Streamerizes PIC16 debug info, which escaped my attention.
This removes a leak from LLVMTargetMachine of the 'legacy'
output stream.
llvm-svn: 100327
EmitInlineAsm. However, this attempt is foiled by operands
being emitted directly to "O" so I'll have to do some surgery
and finish MCizing the world.
llvm-svn: 100291
representation. This eliminates the 'DILocation' MDNodes for
file/line/col tuples from -O0 -g codegen.
This remove the old DebugLoc class, making it a typedef for DebugLoc,
I'll rename NewDebugLoc next.
I didn't update the JIT to use the new apis, so it will continue to
work, but be as slow as before. Someone should eventually do this
or, better yet, rip out the JIT debug info stuff and build the JIT
on top of MC.
llvm-svn: 100209
create symbols. It is extremely error prone and a source of a lot
of the remaining integrated assembler bugs on x86-64.
This fixes rdar://7807601.
llvm-svn: 99902
to LLVM IR changes with addr label weirdness. In the testcase, we
generate references to the two bb's when codegen'ing the first
function:
_test1: ## @test1
leaq Ltmp0(%rip), %rax
..
leaq Ltmp1(%rip), %rax
Then continue to codegen the second function where the blocks
get merged. We're now smart enough to emit both labels, producing
this code:
_test_fun: ## @test_fun
## BB#0: ## %entry
Ltmp1: ## Block address taken
Ltmp0:
## BB#1: ## %ret
movl $-1, %eax
ret
Rejoice.
llvm-svn: 98595
label is generated, but then the block is deleted. Since the
value is undefined, we just emit the label right after the entry
label of the function. It might matter that the label is in the
same section as the function was afterall.
llvm-svn: 98579
an MCSymbol. Make the EH_LABEL MachineInstr hold its label
with an MCSymbol instead of ID. Fix a bug in MMI.cpp which
would return labels named "Label4" instead of "label4".
llvm-svn: 98463
and passing off ownership to AsmPrinter. Now MachineModuleInfo
creates it and owns it by value. This allows us to use MCSymbols
more consistently throughout the rest of the code generator, and
simplifies a bit of code. This also allows MachineFunction to
keep an MCContext reference handy, and cleans up the TargetRegistry
interfaces for AsmPrinters.
llvm-svn: 98450
The major win of this is that the code is simpler and they
print on the same line as the instruction again:
movl %eax, 96(%esp) ## 4-byte Spill
movl 96(%esp), %eax ## 4-byte Reload
cmpl 92(%esp), %eax ## 4-byte Folded Reload
jl LBB7_86
llvm-svn: 95738
into TargetOpcodes.h. #include the new TargetOpcodes.h
into MachineInstr. Add new inline accessors (like isPHI())
to MachineInstr, and start using them throughout the
codebase.
llvm-svn: 95687
in global initializers. Instead of aborting, attempt to fold them on the
spot. If folding succeeds, emit the folded expression instead.
This fixes PR6255.
llvm-svn: 95583
following it. However, the EmitGlobalConstant method wasn't emitting a body for
the constant. The assembler doesn't like that. Before, we were generating this:
.zerofill __DATA, __common, __cmd, 1, 3
This fix puts us back to that semantic.
llvm-svn: 95336
the end of the instruction instead of expecting the caller to
do it. This currently causes the asm-verbose instruction
comments to be on the next line.
llvm-svn: 95178
than DEBUG_VALUE :( ) into the target indep AsmPrinter.cpp
file. This allows elimination of the
NO_ASM_WRITER_BOILERPLATE hack among other things.
llvm-svn: 95177
Move the X86 implementation of function body emission up to
AsmPrinter::EmitFunctionBody, which works by calling the virtual
EmitInstruction method.
llvm-svn: 94716
change is that we now use ".linkonce discard" for global variables
instead of ".linkonce samesize". These should be the same, just less
strict. If anyone is interested in mcizing MCSection for COFF targets,
this should be easy to fix.
llvm-svn: 94623
Default HasSetDirective to true, since most targets have it.
The targets that claim to not have it probably do, or it is
spelled differently. These include Blackfin, Mips, Alpha, and
PIC16. All of these except pic16 are normal ELF targets, so
they almost certainly have it.
llvm-svn: 94585
which is more convenient, and change getPICJumpTableRelocBaseExpr
to take a MachineFunction to match.
Next, move the X86 code that create a PICBase symbol to
X86TargetLowering::getPICBaseSymbol from
X86MCInstLower::GetPICBaseSymbol, which was an asmprinter specific
library. This eliminates a 'gross hack', and allows us to
implement X86ISelLowering::getPICJumpTableRelocBaseExpr which now
calls it.
This in turn allows us to eliminate the
X86AsmPrinter::printPICJumpTableSetLabel method, which was the
only overload of printPICJumpTableSetLabel.
llvm-svn: 94526
Owen Anderson