- Allocate MachineMemOperands and MachineMemOperand lists in MachineFunctions.
This eliminates MachineInstr's std::list member and allows the data to be
created by isel and live for the remainder of codegen, avoiding a lot of
copying and unnecessary translation. This also shrinks MemSDNode.
- Delete MemOperandSDNode. Introduce MachineSDNode which has dedicated
fields for MachineMemOperands.
- Change MemSDNode to have a MachineMemOperand member instead of its own
fields with the same information. This introduces some redundancy, but
it's more consistent with what MachineInstr will eventually want.
- Ignore alignment when searching for redundant loads for CSE, but remember
the greatest alignment.
Target-specific code which previously used MemOperandSDNodes with generic
SDNodes now use MemIntrinsicSDNodes, with opcodes in a designated range
so that the SelectionDAG framework knows that MachineMemOperand information
is available.
llvm-svn: 82794
naming scheme used in SelectionDAG, where there are multiple kinds
of "target" nodes, but "machine" nodes are nodes which represent
a MachineInstr.
llvm-svn: 82790
For the AAPCS ABI, SP must always be 4-byte aligned, and at any "public
interface" it must be 8-byte aligned. For the older ARM APCS ABI, the stack
alignment is just always 4 bytes. For X86, we currently align SP at
entry to a function (e.g., to 16 bytes for Darwin), but no stack alignment
is needed at other times, such as for a leaf function.
After discussing this with Dan, I decided to go with the approach of adding
a new "TransientStackAlignment" field to TargetFrameInfo. This value
specifies the stack alignment that must be maintained even in between calls.
It defaults to 1 except for ARM, where it is 4. (Some other targets may
also want to set this if they have similar stack requirements. It's not
currently required for PPC because it sets targetHandlesStackFrameRounding
and handles the alignment in target-specific code.) The existing StackAlignment
value specifies the alignment upon entry to a function, which is how we've
been using it anyway.
llvm-svn: 82767
interest for this, as it currently reserves a register rather than using
the scavenger for matierializing constants as needed.
Instead of scavenging registers on the fly while eliminating frame indices,
new virtual registers are created, and then a scavenged collectively in a
post-pass over the function. This isolates the bits that need to interact
with the scavenger, and sets the stage for more intelligent use, and reuse,
of scavenged registers.
For the time being, this is disabled by default. Once the bugs are worked out,
the current scavenging calls in replaceFrameIndices() will be removed and
the post-pass scavenging will be the default. Until then,
-enable-frame-index-scavenging enables the new code. Currently, only the
Thumb1 back end is set up to use it.
llvm-svn: 82734
default implementation. Update comment on the default version, which made it
sound like most targets override it. Currently only X86 and SystemZ override
this method.
llvm-svn: 82651
And fix a bug with the behavior of min/max instructions formed from
fcmp uge comparisons.
Also, use FiniteOnlyFPMath() for this code instead of UnsafeFPMath,
as it is more specific.
llvm-svn: 82466
feature, either build the JIT in debug mode to enable it by default or pass
-jit-emit-debug to lli.
Right now, the only debug information that this communicates to GDB is call
frame information, since it's already being generated to support exceptions in
the JIT. Eventually, when DWARF generation isn't tied so tightly to AsmPrinter,
it will be easy to push that information to GDB through this interface.
Here's a step-by-step breakdown of how the feature works:
- The JIT generates the machine code and DWARF call frame info
(.eh_frame/.debug_frame) for a function into memory.
- The JIT copies that info into an in-memory ELF file with a symbol for the
function.
- The JIT creates a code entry pointing to the ELF buffer and adds it to a
linked list hanging off of a global descriptor at a special symbol that GDB
knows about.
- The JIT calls a function marked noinline that GDB knows about and has put an
internal breakpoint in.
- GDB catches the breakpoint and reads the global descriptor to look for new
code.
- When sees there is new code, it reads the ELF from the inferior's memory and
adds it to itself as an object file.
- The JIT continues, and the next time we stop the program, we are able to
produce a proper backtrace.
Consider running the following program through the JIT:
#include <stdio.h>
void baz(short z) {
long w = z + 1;
printf("%d, %x\n", w, *((int*)NULL)); // SEGFAULT here
}
void bar(short y) {
int z = y + 1;
baz(z);
}
void foo(char x) {
short y = x + 1;
bar(y);
}
int main(int argc, char** argv) {
char x = 1;
foo(x);
}
Here is a backtrace before this patch:
Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x2aaaabdfbd10 (LWP 25476)]
0x00002aaaabe7d1a8 in ?? ()
(gdb) bt
#0 0x00002aaaabe7d1a8 in ?? ()
#1 0x0000000000000003 in ?? ()
#2 0x0000000000000004 in ?? ()
#3 0x00032aaaabe7cfd0 in ?? ()
#4 0x00002aaaabe7d12c in ?? ()
#5 0x00022aaa00000003 in ?? ()
#6 0x00002aaaabe7d0aa in ?? ()
#7 0x01000002abe7cff0 in ?? ()
#8 0x00002aaaabe7d02c in ?? ()
#9 0x0100000000000001 in ?? ()
#10 0x00000000014388e0 in ?? ()
#11 0x00007fff00000001 in ?? ()
#12 0x0000000000b870a2 in llvm::JIT::runFunction (this=0x1405b70,
F=0x14024e0, ArgValues=@0x7fffffffe050)
at /home/rnk/llvm-gdb/lib/ExecutionEngine/JIT/JIT.cpp:395
#13 0x0000000000baa4c5 in llvm::ExecutionEngine::runFunctionAsMain
(this=0x1405b70, Fn=0x14024e0, argv=@0x13f06f8, envp=0x7fffffffe3b0)
at /home/rnk/llvm-gdb/lib/ExecutionEngine/ExecutionEngine.cpp:377
#14 0x00000000007ebd52 in main (argc=2, argv=0x7fffffffe398,
envp=0x7fffffffe3b0) at /home/rnk/llvm-gdb/tools/lli/lli.cpp:208
And a backtrace after this patch:
Program received signal SIGSEGV, Segmentation fault.
0x00002aaaabe7d1a8 in baz ()
(gdb) bt
#0 0x00002aaaabe7d1a8 in baz ()
#1 0x00002aaaabe7d12c in bar ()
#2 0x00002aaaabe7d0aa in foo ()
#3 0x00002aaaabe7d02c in main ()
#4 0x0000000000b870a2 in llvm::JIT::runFunction (this=0x1405b70,
F=0x14024e0, ArgValues=...)
at /home/rnk/llvm-gdb/lib/ExecutionEngine/JIT/JIT.cpp:395
#5 0x0000000000baa4c5 in llvm::ExecutionEngine::runFunctionAsMain
(this=0x1405b70, Fn=0x14024e0, argv=..., envp=0x7fffffffe3c0)
at /home/rnk/llvm-gdb/lib/ExecutionEngine/ExecutionEngine.cpp:377
#6 0x00000000007ebd52 in main (argc=2, argv=0x7fffffffe3a8,
envp=0x7fffffffe3c0) at /home/rnk/llvm-gdb/tools/lli/lli.cpp:208
llvm-svn: 82418
U lib/CodeGen/AsmPrinter/DwarfException.cpp
U lib/CodeGen/AsmPrinter/DwarfException.h
--- Reverse-merging r82274 into '.':
U lib/Target/TargetLoweringObjectFile.cpp
G lib/CodeGen/AsmPrinter/DwarfException.cpp
These revisions were breaking everything.
llvm-svn: 82396
internal, they shouldn't use the indirect pointer stuff. In the case of
throw_rethrow_test, it was marked as 'internal' and calculated its own offset to
its contents.
llvm-svn: 82354
into the __DATA section. At launch time, dyld has to update most of the section
to fix up the type info pointers. It's better to place it into the __TEXT
section and use pc-rel indirect pointer encodings. Similar to the personality
routine.
llvm-svn: 82274
getSymbolForDwarfGlobalReference is smart enough to know that it
needs to register the stub it references with MachineModuleInfoMachO,
so that it gets emitted at the end of the file.
Move stub emission from X86ATTAsmPrinter::doFinalization to the
new X86ATTAsmPrinter::EmitEndOfAsmFile asmprinter hook. The important
thing here is that EmitEndOfAsmFile is called *after* the ehframes are
emitted, so we get all the stubs.
This allows us to remove a gross hack from the asmprinter where it would
"just know" that it needed to output stubs for personality functions.
Now this is all driven from a consistent interface.
The testcase change is just reordering the expected output now that the
stubs come out after the ehframe instead of before.
This also unblocks other changes that Bill wants to make.
llvm-svn: 82269
trying to create RMW opportunities in the x86 backend. This can cause a
cycle to appear in the graph, since the other uses may eventually feed into
the TokenFactor we are sinking the load below.
llvm-svn: 81996
the Intel instruction tables.
The patterns will stay blank because ADD reg, reg
is faster, but having the encoding available is
useful for the disassembler.
llvm-svn: 81994
Eliminate the PersonalityPrefix/Suffix & NeedsIndirectEncoding
fields from MAI: they aren't part of the asm syntax, they are
related to the structure of the object file.
To replace their functionality, add a new
TLOF::getSymbolForDwarfGlobalReference method which asks targets
to decide how to reference a global from EH in a pc-relative way.
The default implementation just returns the symbol. The default
darwin implementation references the symbol through an indirect
$non_lazy_ptr stub. The bizarro x86-64 darwin specialization
handles the weird "foo@GOTPCREL+4" hack.
DwarfException.cpp now uses this to emit the reference to the
symbol in the right way, and this also eliminates another
horrible hack from DwarfException.cpp:
- if (strcmp(MAI->getPersonalitySuffix(), "+4@GOTPCREL"))
- O << "-" << MAI->getPCSymbol();
llvm-svn: 81991
All of these do not have patterns (they're for the
disassembler).
Many of the floating-point instructions will probably
be rolled into definitions that have patterns, and may
eventually be superseded by mdefs. So I put them
together and left a comment.
llvm-svn: 81979
and use PersonalityPrefix/Suffix to achieve the same effect (like
the x86 backend).
This changes the code generated for ppc static mode, but guess what,
we were generating this before:
.byte 0x9B ; Personality (indirect pcrel sdata4)
.long ___gxx_personality_v0-. ; Personality
which is not correct! (it is not an 'indirect' reference).
llvm-svn: 81965
interrupt instruction, which shouldn't arise any other way). 0xcd is
also used by JITMemoryManager to initialize the buffer to garbage,
which means it could appear following a noreturn call even when
that is not a stub, confusing X86CompilationCallback2. PR 4929.
llvm-svn: 81888
VLDM/VSTM instructions, and without this check, the code assumes that an
offset is allowed, as it would be with VLDR/VSTR. The asm printer,
however, silently drops the offset, producing incorrect code. Since the
address register in this case is either the stack or frame pointer, the
spill location ends up conflicting with some other stack slot or with
outgoing arguments on the stack.
llvm-svn: 81879
has multiple uses, as one of the other uses may be on a path
to a different node above the callseq_start, because that
leads to a cyclic graph. This problem is exposed when
-combiner-global-alias-analysis is used. This fixes PR4880.
llvm-svn: 81821
parses the .word directive as 4 bytes and ARMAsmParser::ParseInstruction will
give an error is called. Broke out the test of the .word directive into two
different test cases, one for x86 and one for arm.
llvm-svn: 81817
full AsmPrinter, and change TargetRegistry to keep track
of registered MCInstPrinters.
llvm-mc is still linking in the entire
target foo to get the code emitter stuff, but this is an
important step in the right direction.
llvm-svn: 81754
Change the picbase symbol on non-darwin systems from ".Lllvm$4.$piclabel" to
".L4$pb". The actual name doesn't matter and the darwin name is shorter.
llvm-svn: 81688
Move GetMBBSymbol up to AsmPrinter and make printBasicBlockLabel use it so that
we only have one place that decides what to name bb labels. Hopefully various
clients of printBasicBlockLabel can start using GetMBBSymbol instead.
llvm-svn: 81652
this means that it can only lower one MachineInstr to one MCInst. To
make this fly, we need to pull out handling of MO_GOT_ABSOLUTE_ADDRESS
(which generates an implicit label) out of X86MCInstLower.
llvm-svn: 81629
more efficient SmallPtrSet<MCSymbol*>. This eliminates string
craziness and fixes CodeGen/X86/darwin-quote.ll with the new asmprinter.
Codegen is producing stubs in a nondeterminstic order, but it was doing
this before anyway.
llvm-svn: 81511
Mangler::getNameWithPrefix. In addition to avoiding some over
quoting, this also is more efficient because it uses smallvector
instead of std::string thrashing.
llvm-svn: 81508
safe. This can happen we a subreg_to_reg 0 has been coalesced. One
exception is when the instruction that folds the load is a move, then we
can simply turn it into a 32-bit load from the stack slot.
rdar://7170444
llvm-svn: 81494
that things like .word can be parsed as target specific. Moved parsing .word
out of AsmParser.cpp into X86AsmParser.cpp as it is 2 bytes on X86 and 4 bytes
for other targets that support the .word directive.
llvm-svn: 81461
the MCInst path of the asmprinter. Instead, pull comment printing
out of the autogenerated asmprinter into each target that uses the
autogenerated asmprinter. This causes code duplication into each
target, but in a way that will be easier to clean up later when more
asmprinter stuff is commonized into the base AsmPrinter class.
This also fixes an xcore strangeness where it inserted two tabs
before every instruction.
llvm-svn: 81396
asm printer into the "printInstruction" routine. This
fixes a problem where the experimental asmprinter would
drop debug labels in some cases, and fixes issues on ppc/xcore
where pseudo instructions like "mr" didn't get debug locs properly.
It is annoying that this moves the call from one place into each
target, but a future set of more invasive refactorings will fix
that problem.
llvm-svn: 81377
to instructions instead of zero extended ones. This makes the asmprinter
print signed values more consistently. This apparently only really affects
the X86 backend.
llvm-svn: 81265
depth first order, so it wouldn't process unreachable blocks.
When compiling at -O0, late dead block elimination isn't done
and the bad instructions got to isel.
llvm-svn: 81187
- when transforming a vector shift of a non-immediate scalar shift amount, zero
extend the i32 shift amount to i64 since the vector shift reads 64 bits
- when transforming i16 vectors to use a vector shift, zero extend i16 shift amount
- improve the code quality in some cases when transforming vectors to use a vector shift
llvm-svn: 80935
disabling the use of 16-bit operations on x86. This doesn't yet work for
inline asms with 16-bit constraints, vectors with 16-bit elements,
trampoline code, and perhaps other obscurities, but it's enough to try
some experiments.
llvm-svn: 80930
from MCAsmLexer.h in preparation of supporting other targets. Changed the
X86AsmParser code to reflect this by removing AsmLexer::LexPercent and looking
for AsmToken::Percent when parsing in places that used AsmToken::Register.
Then changed X86ATTAsmParser::ParseRegister to parse out registers as an
AsmToken::Percent followed by an AsmToken::Identifier.
llvm-svn: 80929
different formatting from the old asmprinter, but it should be
semantically the same. We used to get:
popl %eax
addl $_GLOBAL_OFFSET_TABLE_ + [.-.Lllvm$6.$piclabel], %eax
...
Now we get:
popl %eax
.Lpicbaseref6:
addl $(_GLOBAL_OFFSET_TABLE_ + (.Lpicbaseref6 - .Lllvm$6.$piclabel)), %eax
...
llvm-svn: 80905