Currently there is no instruction encoding info and
XCoreDisassembler::getInstruction() always returns Fail. I intend to add
instruction encodings and tests in follow on commits.
llvm-svn: 170292
Mips16 is really a processor decoding mode (ala thumb 1) and in the same
program, mips16 and mips32 functions can exist and can call each other.
If a jal type instruction encounters an address with the lower bit set, then
the processor switches to mips16 mode (if it is not already in it). If the
lower bit is not set, then it switches to mips32 mode.
The linker knows which functions are mips16 and which are mips32.
When relocation is performed on code labels, this lower order bit is
set if the code label is a mips16 code label.
In general this works just fine, however when creating exception handling
tables and dwarf, there are cases where you don't want this lower order
bit added in.
This has been traditionally distinguished in gas assembly source by using a
different syntax for the label.
lab1: ; this will cause the lower order bit to be added
lab2=. ; this will not cause the lower order bit to be added
In some cases, it does not matter because in dwarf and debug tables
the difference of two labels is used and in that case the lower order
bits subtract each other out.
To fix this, I have added to mcstreamer the notion of a debuglabel.
The default is for label and debug label to be the same. So calling
EmitLabel and EmitDebugLabel produce the same result.
For various reasons, there is only one set of labels that needs to be
modified for the mips exceptions to work. These are the "$eh_func_beginXXX"
labels.
Mips overrides the debug label suffix from ":" to "=." .
This initial patch fixes exceptions. More changes most likely
will be needed to DwarfCFException to make all of this work
for actual debugging. These changes will be to emit debug labels in some
places where a simple label is emitted now.
Some historical discussion on this from gcc can be found at:
http://gcc.gnu.org/ml/gcc-patches/2008-08/msg00623.htmlhttp://gcc.gnu.org/ml/gcc-patches/2008-11/msg01273.html
llvm-svn: 170279
We match the pattern "x >= y ? x-y : 0" into "subus x, y" and two special cases
if y is a constant. DAGCombiner canonicalizes those so we first have to undo the
canonicalization for those cases. The pattern occurs in gzip when the loop
vectorizer is enabled. Part of PR14613.
llvm-svn: 170273
Not all chips targeted by x86_64 have this feature, but a dramatically
increasing number do. Specifying a chip-specific tuning parameter will
continue to turn the feature on or off as appropriate for that
particular chip, but the generic flag should try to achieve the best
performance on the most widely available hardware. Today, the number of
chips with fast UA access dwarfs those without in the x86-64 space.
Note that this also brings LLVM's code generation for this '-march' flag
more in line with that of modern GCCs. Reviewed by Dan Gohman.
llvm-svn: 170269
In this case, essentially it is soft float with different library routines.
The next step will be to make this fully interoperational with mips32 floating
point and that requires creating stubs for functions with signatures that
contain floating point types.
I have a more sophisticated design for mips16 hardfloat which I hope to
implement at a later time that directly does floating point without the need
for function calls.
The mips16 encoding has no floating point instructions so one needs to
switch to mips32 mode to execute floating point instructions.
llvm-svn: 170259
immediate generates the narrow version. Needed when doing round-trip
assemble/disassemble testing using the alternate syntax that specifies
'pc' directly.
llvm-svn: 170255
for TLS dynamic models on 64-bit PowerPC ELF. The default sort routine
for relocations only sorts on the r_offset field; but with TLS, there
can be two relocations with the same r_offset. For PowerPC, this patch
sorts secondarily on descending r_type, which matches the behavior
expected by the linker.
llvm-svn: 170237
for a wider range of GOT entries that can hold thread-relative offsets.
This matches the behavior of GCC, which was not documented in the PPC64 TLS
ABI. The ABI will be updated with the new code sequence.
Former sequence:
ld 9,x@got@tprel(2)
add 9,9,x@tls
New sequence:
addis 9,2,x@got@tprel@ha
ld 9,x@got@tprel@l(9)
add 9,9,x@tls
Note that a linker optimization exists to transform the new sequence into
the shorter sequence when appropriate, by replacing the addis with a nop
and modifying the base register and relocation type of the ld.
llvm-svn: 170209
some hackery in place that hid my poor use of TblGen, which I've now sorted
out and cleaned up. No change in observable behavior, so no new test cases.
llvm-svn: 170149
Accordingly, add helper funtions getSimpleValueType (in parallel to
getValueType) in SDValue, SDNode, and TargetLowering.
This is the first, in a series of patches.
This is the second attempt. In the first attempt (r169837), a few
getSimpleVT() were hoisted too far, detected by bootstrap failures.
llvm-svn: 170104
PowerPC target. This is the last of the four models, so we now have
full TLS support.
This is mostly a straightforward extension of the general dynamic model.
I had to use an additional Chain operand to tie ADDIS_DTPREL_HA to the
register copy following ADDI_TLSLD_L; otherwise everything above the
ADDIS_DTPREL_HA appeared dead and was removed.
As before, there are new test cases to test the assembly generation, and
the relocations output during integrated assembly. The expected code
gen sequence can be read in test/CodeGen/PowerPC/tls-ld.ll.
There are a couple of things I think can be done more efficiently in the
overall TLS code, so there will likely be a clean-up patch forthcoming;
but for now I want to be sure the functionality is in place.
Bill
llvm-svn: 170003
Add R_ARM_NONE and R_ARM_PREL31 relocation types
to MCExpr. Both of them will be used while
generating .ARM.extab and .ARM.exidx sections.
llvm-svn: 169965
mention the inline memcpy / memset expansion code is a mess?
This patch split the ZeroOrLdSrc argument into two: IsMemset and ZeroMemset.
The first indicates whether it is expanding a memset or a memcpy / memmove.
The later is whether the memset is a memset of zero. It's totally possible
(likely even) that targets may want to do different things for memcpy and
memset of zero.
llvm-svn: 169959
Also added more comments to explain why it is generally ok to return true.
- Rename getOptimalMemOpType argument IsZeroVal to ZeroOrLdSrc. It's meant to
be true for loaded source (memcpy) or zero constants (memset). The poor name
choice is probably some kind of legacy issue.
llvm-svn: 169954
ScalarTargetTransformInfo::getIntImmCost() instead. "Legal" is a poorly defined
term for something like integer immediate materialization. It is always possible
to materialize an integer immediate. Whether to use it for memcpy expansion is
more a "cost" conceern.
llvm-svn: 169929
Richard Osborne