Commit Graph

156 Commits

Author SHA1 Message Date
Hal Finkel
946a811ef1 PPC rotate instructions don't have unmodeled side effcts
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178982 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-07 15:06:53 +00:00
Hal Finkel
f0e3ca012b Most PPC M[TF]CR instructions do not have side effects
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178978 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-07 14:33:13 +00:00
Hal Finkel
3aea7cb7b2 PPC pre-increment load instructions do not have side effects
A few were missed in r178972.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178973 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-07 06:30:47 +00:00
Hal Finkel
fa1d102a05 PPC pre-increment load instructions do not have side effects
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178972 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-07 05:46:58 +00:00
Hal Finkel
012ffd5605 PPC ISEL is a select and never has side effects
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178960 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-06 19:30:28 +00:00
Hal Finkel
4647919784 Add more PPC floating-point conversion instructions
The P7 and A2 have additional floating-point conversion instructions which
allow a direct two-instruction sequence (plus load/store) to convert from all
combinations (signed/unsigned i32/i64) <--> (float/double) (on previous cores,
only some combinations were directly available).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178480 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-01 17:52:07 +00:00
Hal Finkel
1fce88313e Add the PPC popcntw instruction
The popcntw instruction is available whenever the popcntd instruction is
available, and performs a separate popcnt on the lower and upper 32-bits.
Ignoring the high-order count, this can be used for the 32-bit input case
(saving on the explicit zero extension otherwise required to use popcntd).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178470 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-01 15:58:15 +00:00
Hal Finkel
9ad0f4907b Cleanup PPC(64) i32 -> float/double conversion
The existing SINT_TO_FP code for i32 -> float/double conversion was disabled
because it relied on broken EXTSW_32/STD_32 instruction definitions. The
original intent had been to enable these 64-bit instructions to be used on CPUs
that support them even in 32-bit mode.  Unfortunately, this form of lying to
the infrastructure was buggy (as explained in the FIXME comment) and had
therefore been disabled.

This re-enables this functionality, using regular DAG nodes, but only when
compiling in 64-bit mode. The old STD_32/EXTSW_32 definitions (which were dead)
are removed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178438 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-31 01:58:02 +00:00
Hal Finkel
efdd4673d6 Add the PPC64 ldbrx/stdbrx instructions
These are 64-bit load/store with byte-swap, and available on the P7 and the A2.
Like the similar instructions for 16- and 32-bit words, these are matched in the
target DAG-combine phase against load/store-bswap pairs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178276 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-28 19:25:55 +00:00
Hal Finkel
c53ab4d77f Add the PPC64 popcntd instruction
PPC ISA 2.06 (P7, A2, etc.) has a popcntd instruction. Add this instruction and
tell TTI about it so that popcount-loop recognition will know about it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178233 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-28 13:29:47 +00:00
Hal Finkel
d01efc737a Fix typo in PPCInstr64Bit
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178219 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-28 03:38:08 +00:00
Hal Finkel
6375e1b87b Use the PPC no-r0 class on the TOC LD pseudos
The register parameter in these instructions becomes the base register in an
r+i ld instruction (and, thus, cannot be r0).

This is not yet testable because we don't yet allocate r0 (and even then any
test would be very fragile).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178121 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-27 06:36:55 +00:00
Hal Finkel
56d926ac14 Apply the no-r0 class to PPC TOC ADDI[S] pseudo instructions
Like the addi/addis instructions themselves, these pseudo instructions also
cannot have r0 as their register parameter (because it will be interpreted as
the value 0).

This is not yet testable because we don't yet allocate r0 (and even when we do,
any regression test would be very fragile because it would depend on the
register allocator heuristics).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178118 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-27 05:57:56 +00:00
Ulrich Weigand
3d386421e0 PowerPC: Mark patterns as isCodeGenOnly.
There remain a number of patterns that cannot (and should not)
be handled by the asm parser, in particular all the Pseudo patterns.

This commit marks those patterns as isCodeGenOnly.

No change in generated code.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178008 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26 10:57:16 +00:00
Ulrich Weigand
d67768db80 PowerPC: Remove LDrs pattern.
The LDrs pattern is a duplicate of LD, except that it accepts memory
addresses where the displacement is a symbolLo64.  An operand type
"memrs" is defined for just that purpose.

However, this wouldn't be necessary if the default "memrix" operand
type were to simply accept 64-bit symbolic addresses directly.
The only problem with that is that it uses "symbolLo", which is
hardcoded to 32-bit.

To fix this, this commit changes "memri" and "memrix" to use new
operand types for the memory displacement, which allow iPTR
instead of i32.  This will also make address parsing easier to
implment in the asm parser.

No change in generated code.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178005 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26 10:55:45 +00:00
Ulrich Weigand
2b0850b830 PowerPC: Remove ADDIL patterns.
The ADDI/ADDI8 patterns are currently duplicated into ADDIL/ADDI8L,
which describe the same instruction, except that they accept a
symbolLo[64] operand instead of a s16imm[64] operand.

This duplication confuses the asm parser, and it actually not really
needed, since symbolLo[64] already accepts immediate operands anyway.
So this commit removes the duplicate patterns.

No change in generated code.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178004 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26 10:55:20 +00:00
Ulrich Weigand
a01c7dbaab PowerPC: Use CCBITRC operand for ISEL patterns.
This commit changes the ISEL patterns to use a CCBITRC operand
instead of a "pred" operand.  This matches the actual instruction
text more directly, and simplifies use of ISEL with the asm parser.
In addition, this change allows some simplification of handling
the "pred" operand, as this is now only used by BCC.

No change in generated code.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178003 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26 10:54:54 +00:00
Ulrich Weigand
e8680da874 PowerPC: Move some 64-bit branch patterns.
In PPCInstr64Bit.td, some branch patterns appear in a different sequence
than the corresponding 32-bit patterns in PPCInstrInfo.td.

To simplify future changes that affect both files, this commit moves
those patterns to rearrange them into a similar sequence.

No effect on generated code.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178001 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26 10:53:03 +00:00
Ulrich Weigand
5b390e4cd8 Use direct types in PowerPC instruction patterns.
This commit updates the PowerPC back-end (PPCInstrInfo.td and
PPCInstr64Bit.td) to use types instead of register classes in
instruction patterns, along the lines of Jakob Stoklund Olesen's
changes in r177835 for Sparc.
 


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177890 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-25 19:05:30 +00:00
Ulrich Weigand
1492a4e518 Use direct types in PowerPC Pat patterns.
This commit updates the PowerPC back-end (PPCInstrInfo.td and
PPCInstr64Bit.td) to use types instead of register classes in
Pat patterns, along the lines of Jakob Stoklund Olesen's
changes in r177829 for Sparc.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177889 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-25 19:04:58 +00:00
Ulrich Weigand
86765fbe17 Remove ABI-duplicated call instruction patterns.
We currently have a duplicated set of call instruction patterns depending
on the ABI to be followed (Darwin vs. Linux).  This is a bit odd; while the
different ABIs will result in different instruction sequences, the actual
instructions themselves ought to be independent of the ABI.  And in fact it
turns out that the only nontrivial difference between the two sets of
patterns is that in the PPC64 Linux ABI, the instruction used for indirect
calls is marked to take X11 as extra input register (which is indeed used
only with that ABI to hold an incoming environment pointer for nested
functions).  However, this does not need to be hard-coded at the .td
pattern level; instead, the C++ code expanding calls can simply add that
use, just like it adds uses for argument registers anyway.

No change in generated code expected.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177735 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-22 15:24:13 +00:00
Ulrich Weigand
89ec847ec7 Rename memrr ptrreg and offreg components.
Currently, the sub-operand of a memrr address that corresponds to what
hardware considers the base register is called "offreg", while the
sub-operand that corresponds to the offset is called "ptrreg".

To avoid confusion, this patch simply swaps the named of those two
sub-operands and updates all uses.  No functional change is intended.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177734 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-22 14:59:13 +00:00
Ulrich Weigand
881a7154b9 Fix swapped BasePtr and Offset in pre-inc memory addresses.
PPCTargetLowering::getPreIndexedAddressParts currently provides
the base part of a memory address in the offset result, and the
offset part in the base result.  That swap is then undone again
when an MI instruction is generated (in PPCDAGToDAGISel::Select
for loads, and using .md Pat patterns for stores).

This patch reverts this double swap, to make common code and
back-end be in sync as to which part of the address is base
and which is offset.

To avoid performance regressions in certain cases, target code
now checks whether the choice of base register would be rejected
for pre-inc accesses by common code, and attempts to swap base
and offset again in such cases.  (Overall, this means that now
pre-ice accesses are generated *more* frequently than before.)



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177733 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-22 14:58:48 +00:00
Ulrich Weigand
cff0faa16a Remove the xaddroff ComplexPattern.
The xaddroff pattern is currently (mistakenly) used to recognize
the *base* register in pre-inc store patterns.  This patch replaces
those uses by ptr_rc_nor0 (as is elsewhere done to match the base
register of an address), and removes the now unused ComplexPattern.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177731 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-22 14:57:48 +00:00
Hal Finkel
3ea1b064a0 Fix a register-class comparison bug in PPCCTRLoops
Thanks to Jakob for isolating the underlying problem from the
test case in r177423. The original commit had introduced
asymmetric copy operations, but these turned out to be a work-around
to the real problem (the use of == instead of hasSubClassEq in PPCCTRLoops).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177679 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-21 23:23:34 +00:00
Hal Finkel
7ee74a663a Implement builtin_{setjmp/longjmp} on PPC
This implements SJLJ lowering on PPC, making the Clang functions
__builtin_{setjmp/longjmp} functional on PPC platforms. The implementation
strategy is similar to that on X86, with the exception that a branch-and-link
variant is used to get the right jump address. Credit goes to Bill Schmidt for
suggesting the use of the unconditional bcl form (instead of the regular bl
instruction) to limit return-address-cache pollution.

Benchmarking the speed at -O3 of:

static jmp_buf env_sigill;

void foo() {
                __builtin_longjmp(env_sigill,1);
}

main() {
	...

        for (int i = 0; i < c; ++i) {
                if (__builtin_setjmp(env_sigill)) {
                        goto done;
                } else {
                        foo();
                }

done:;
        }

	...
}

vs. the same code using the libc setjmp/longjmp functions on a P7 shows that
this builtin implementation is ~4x faster with Altivec enabled and ~7.25x
faster with Altivec disabled. This comparison is somewhat unfair because the
libc version must also save/restore the VSX registers which we don't yet
support.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177666 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-21 21:37:52 +00:00
Ulrich Weigand
dff4d1522a Add missing mayLoad flag to LHAUX8 and LWAUX.
All pre-increment load patterns need to set the mayLoad flag (since
they don't provide a DAG pattern).

This was missing for LHAUX8 and LWAUX, which is added by this patch.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177431 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-19 19:53:27 +00:00
Ulrich Weigand
8353d1e0e5 Rewrite LHAU8 pattern to use standard memory operand.
As opposed to to pre-increment store patterns, the pre-increment
load patterns were already using standard memory operands, with
the sole exception of LHAU8.

As there's no real reason why LHAU8 should be different here,
this patch simply rewrites the pattern to also use a memri
operand, just like all the other patterns.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177430 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-19 19:52:30 +00:00
Ulrich Weigand
5882e3d828 Rewrite pre-increment store patterns to use standard memory operands.
Currently, pre-increment store patterns are written to use two separate
operands to represent address base and displacement:

  stwu $rS, $ptroff($ptrreg)

This causes problems when implementing the assembler parser, so this
commit changes the patterns to use standard (complex) memory operands
like in all other memory access instruction patterns:

  stwu $rS, $dst

To still match those instructions against the appropriate pre_store
SelectionDAG nodes, the patch uses the new feature that allows a Pat
to match multiple DAG operands against a single (complex) instruction
operand.

Approved by Hal Finkel.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177429 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-19 19:52:04 +00:00
Ulrich Weigand
880d82e3db Fix sub-operand size mismatch in tocentry operands.
The tocentry operand class refers to 64-bit values (it is only used in 64-bit,
where iPTR is a 64-bit type), but its sole suboperand is designated as 32-bit
type.  This causes a mismatch to be detected at compile-time with the TableGen
patch I'll check in shortly.

To fix this, this commit changes the suboperand to a 64-bit type as well.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177427 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-19 19:50:30 +00:00
Hal Finkel
a548afc98f Prepare to make r0 an allocatable register on PPC
Currently the PPC r0 register is unconditionally reserved. There are two reasons
for this:

 1. r0 is treated specially (as the constant 0) by certain instructions, and so
    cannot be used with those instructions as a regular register.

 2. r0 is used as a temporary register in the CR-register spilling process
    (where, under some circumstances, we require two GPRs).

This change addresses the first reason by introducing a restricted register
class (without r0) for use by those instructions that treat r0 specially. These
register classes have a new pseudo-register, ZERO, which represents the r0-as-0
use. This has the side benefit of making the existing target code simpler (and
easier to understand), and will make it clear to the register allocator that
uses of r0 as 0 don't conflict will real uses of the r0 register.

Once the CR spilling code is improved, we'll be able to allocate r0.

Adding these extra register classes, for some reason unclear to me, causes
requests to the target to copy 32-bit registers to 64-bit registers. The
resulting code seems correct (and causes no test-suite failures), and the new
test case covers this new kind of asymmetric copy.

As r0 is still reserved, no functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177423 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-19 18:51:05 +00:00
Hal Finkel
ec2e968b7a Cleanup PPC64 unaligned i64 load/store
Remove an accidentally-added instruction definition and add a comment in the
test case. This is in response to a post-commit review by Bill Schmidt.

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177404 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-19 15:23:39 +00:00
Hal Finkel
08a215c286 Fix PPC unaligned 64-bit loads and stores
PPC64 supports unaligned loads and stores of 64-bit values, but
in order to use the r+i forms, the offset must be a multiple of 4.
Unfortunately, this cannot always be determined by examining the
immediate itself because it might be available only via a TOC entry.

In order to get around this issue, we additionally predicate the
selection of the r+i form on the alignment of the load or store
(forcing it to be at least 4 in order to select the r+i form).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177338 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-18 23:00:58 +00:00
Bill Schmidt
53b0b0e754 Large code model support for PowerPC.
Large code model is identical to medium code model except that the
addis/addi sequence for "local" accesses is never used.  All accesses
use the addis/ld sequence.

The coding changes are straightforward; most of the patch is taken up
with creating variants of the medium model tests for large model.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175767 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-21 17:12:27 +00:00
Bill Schmidt
b453e16855 This patch improves the 64-bit PowerPC InitialExec TLS support by providing
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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170209 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-14 17:02:38 +00:00
Bill Schmidt
1e18b86192 This is another cleanup patch for 64-bit PowerPC TLS processing. I had
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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170149 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-13 20:57:10 +00:00
Bill Schmidt
dfebc4cc4c This is just a clean-up patch that simplifies the initial-exec TLS logic by
avoiding use of machine operand flags.  No change in observable behavior, so
no new test cases.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170141 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-13 18:45:54 +00:00
Bill Schmidt
349c2787cf This patch implements local-dynamic TLS model support for the 64-bit
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


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170003 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-12 19:29:35 +00:00
Bill Schmidt
57ac1f458a This patch implements the general dynamic TLS model for 64-bit PowerPC.
Given a thread-local symbol x with global-dynamic access, the generated
code to obtain x's address is:

     Instruction                            Relocation            Symbol
  addis ra,r2,x@got@tlsgd@ha           R_PPC64_GOT_TLSGD16_HA       x
  addi  r3,ra,x@got@tlsgd@l            R_PPC64_GOT_TLSGD16_L        x
  bl __tls_get_addr(x@tlsgd)           R_PPC64_TLSGD                x
                                       R_PPC64_REL24           __tls_get_addr
  nop
  <use address in r3>

The implementation borrows from the medium code model work for introducing
special forms of ADDIS and ADDI into the DAG representation.  This is made
slightly more complicated by having to introduce a call to the external
function __tls_get_addr.  Using the full call machinery is overkill and,
more importantly, makes it difficult to add a special relocation.  So I've
introduced another opcode GET_TLS_ADDR to represent the function call, and
surrounded it with register copies to set up the parameter and return value.

Most of the code is pretty straightforward.  I ran into one peculiarity
when I introduced a new PPC opcode BL8_NOP_ELF_TLSGD, which is just like
BL8_NOP_ELF except that it takes another parameter to represent the symbol
("x" above) that requires a relocation on the call.  Something in the 
TblGen machinery causes BL8_NOP_ELF and BL8_NOP_ELF_TLSGD to be treated
identically during the emit phase, so this second operand was never
visited to generate relocations.  This is the reason for the slightly
messy workaround in PPCMCCodeEmitter.cpp:getDirectBrEncoding().

Two new tests are included to demonstrate correct external assembly and
correct generation of relocations using the integrated assembler.

Comments welcome!

Thanks,
Bill


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169910 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-11 20:30:11 +00:00
Bill Schmidt
d7802bf0dd This patch introduces initial-exec model support for thread-local storage
on 64-bit PowerPC ELF.

The patch includes code to handle external assembly and MC output with the
integrated assembler.  It intentionally does not support the "old" JIT.

For the initial-exec TLS model, the ABI requires the following to calculate
the address of external thread-local variable x:

 Code sequence            Relocation                  Symbol
  ld 9,x@got@tprel(2)      R_PPC64_GOT_TPREL16_DS      x
  add 9,9,x@tls            R_PPC64_TLS                 x

The register 9 is arbitrary here.  The linker will replace x@got@tprel
with the offset relative to the thread pointer to the generated GOT
entry for symbol x.  It will replace x@tls with the thread-pointer
register (13).

The two test cases verify correct assembly output and relocation output
as just described.

PowerPC-specific selection node variants are added for the two
instructions above:  LD_GOT_TPREL and ADD_TLS.  These are inserted
when an initial-exec global variable is encountered by
PPCTargetLowering::LowerGlobalTLSAddress(), and later lowered to
machine instructions LDgotTPREL and ADD8TLS.  LDgotTPREL is a pseudo
that uses the same LDrs support added for medium code model's LDtocL,
with a different relocation type.

The rest of the processing is straightforward.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169281 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-04 16:18:08 +00:00
Bill Schmidt
34a9d4b3b9 This patch implements medium code model support for 64-bit PowerPC.
The default for 64-bit PowerPC is small code model, in which TOC entries
must be addressable using a 16-bit offset from the TOC pointer.  Additionally,
only TOC entries are addressed via the TOC pointer.

With medium code model, TOC entries and data sections can all be addressed
via the TOC pointer using a 32-bit offset.  Cooperation with the linker
allows 16-bit offsets to be used when these are sufficient, reducing the
number of extra instructions that need to be executed.  Medium code model
also does not generate explicit TOC entries in ".section toc" for variables
that are wholly internal to the compilation unit.

Consider a load of an external 4-byte integer.  With small code model, the
compiler generates:

	ld 3, .LC1@toc(2)
	lwz 4, 0(3)

	.section	.toc,"aw",@progbits
.LC1:
	.tc ei[TC],ei

With medium model, it instead generates:

	addis 3, 2, .LC1@toc@ha
	ld 3, .LC1@toc@l(3)
	lwz 4, 0(3)

	.section	.toc,"aw",@progbits
.LC1:
	.tc ei[TC],ei

Here .LC1@toc@ha is a relocation requesting the upper 16 bits of the
32-bit offset of ei's TOC entry from the TOC base pointer.  Similarly,
.LC1@toc@l is a relocation requesting the lower 16 bits.  Note that if
the linker determines that ei's TOC entry is within a 16-bit offset of
the TOC base pointer, it will replace the "addis" with a "nop", and
replace the "ld" with the identical "ld" instruction from the small
code model example.

Consider next a load of a function-scope static integer.  For small code
model, the compiler generates:

	ld 3, .LC1@toc(2)
	lwz 4, 0(3)

	.section	.toc,"aw",@progbits
.LC1:
	.tc test_fn_static.si[TC],test_fn_static.si
	.type	test_fn_static.si,@object
	.local	test_fn_static.si
	.comm	test_fn_static.si,4,4

For medium code model, the compiler generates:

	addis 3, 2, test_fn_static.si@toc@ha
	addi 3, 3, test_fn_static.si@toc@l
	lwz 4, 0(3)

	.type	test_fn_static.si,@object
	.local	test_fn_static.si
	.comm	test_fn_static.si,4,4

Again, the linker may replace the "addis" with a "nop", calculating only
a 16-bit offset when this is sufficient.

Note that it would be more efficient for the compiler to generate:

	addis 3, 2, test_fn_static.si@toc@ha
        lwz 4, test_fn_static.si@toc@l(3)

The current patch does not perform this optimization yet.  This will be
addressed as a peephole optimization in a later patch.

For the moment, the default code model for 64-bit PowerPC will remain the
small code model.  We plan to eventually change the default to medium code
model, which matches current upstream GCC behavior.  Note that the different
code models are ABI-compatible, so code compiled with different models will
be linked and execute correctly.

I've tested the regression suite and the application/benchmark test suite in
two ways:  Once with the patch as submitted here, and once with additional
logic to force medium code model as the default.  The tests all compile
cleanly, with one exception.  The mandel-2 application test fails due to an
unrelated ABI compatibility with passing complex numbers.  It just so happens
that small code model was incredibly lucky, in that temporary values in 
floating-point registers held the expected values needed by the external
library routine that was called incorrectly.  My current thought is to correct
the ABI problems with _Complex before making medium code model the default,
to avoid introducing this "regression."

Here are a few comments on how the patch works, since the selection code
can be difficult to follow:

The existing logic for small code model defines three pseudo-instructions:
LDtoc for most uses, LDtocJTI for jump table addresses, and LDtocCPT for
constant pool addresses.  These are expanded by SelectCodeCommon().  The
pseudo-instruction approach doesn't work for medium code model, because
we need to generate two instructions when we match the same pattern.
Instead, new logic in PPCDAGToDAGISel::Select() intercepts the TOC_ENTRY
node for medium code model, and generates an ADDIStocHA followed by either
a LDtocL or an ADDItocL.  These new node types correspond naturally to
the sequences described above.

The addis/ld sequence is generated for the following cases:
 * Jump table addresses
 * Function addresses
 * External global variables
 * Tentative definitions of global variables (common linkage)

The addis/addi sequence is generated for the following cases:
 * Constant pool entries
 * File-scope static global variables
 * Function-scope static variables

Expanding to the two-instruction sequences at select time exposes the
instructions to subsequent optimization, particularly scheduling.

The rest of the processing occurs at assembly time, in
PPCAsmPrinter::EmitInstruction.  Each of the instructions is converted to
a "real" PowerPC instruction.  When a TOC entry needs to be created, this
is done here in the same manner as for the existing LDtoc, LDtocJTI, and
LDtocCPT pseudo-instructions (I factored out a new routine to handle this).

I had originally thought that if a TOC entry was needed for LDtocL or
ADDItocL, it would already have been generated for the previous ADDIStocHA.
However, at higher optimization levels, the ADDIStocHA may appear in a 
different block, which may be assembled textually following the block
containing the LDtocL or ADDItocL.  So it is necessary to include the
possibility of creating a new TOC entry for those two instructions.

Note that for LDtocL, we generate a new form of LD called LDrs.  This
allows specifying the @toc@l relocation for the offset field of the LD
instruction (i.e., the offset is replaced by a SymbolLo relocation).
When the peephole optimization described above is added, we will need
to do similar things for all immediate-form load and store operations.

The seven "mcm-n.ll" test cases are kept separate because otherwise the
intermingling of various TOC entries and so forth makes the tests fragile
and hard to understand.

The above assumes use of an external assembler.  For use of the
integrated assembler, new relocations are added and used by
PPCELFObjectWriter.  Testing is done with "mcm-obj.ll", which tests for
proper generation of the various relocations for the same sequences
tested with the external assembler.






git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168708 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-27 17:35:46 +00:00
Ulrich Weigand
8f887369cb Fix wrong PowerPC instruction opcodes for:
- lwaux
 - lhzux
 - stbu


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167863 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-13 19:21:31 +00:00
Ulrich Weigand
18430436ca Fix instruction encoding for "bd(n)z" on PowerPC,
by using a new instruction format BForm_1.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167861 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-13 19:15:52 +00:00
Ulrich Weigand
bc40df3f22 Fix instruction encoding for "isel" on PowerPC,
using a new instruction format AForm_4.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167860 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-13 19:14:19 +00:00
Adhemerval Zanella
edf5e9a1d5 PowerPC: Fix for rldcl/rldicl/rldicr MC emission
This patch fixes the rldcl/rldicl/rldicr instruction emission. The issue is
the MDForm_1 instruction defines the PowerISA MB field from 'rldicl'
with the name MBE, but RLDCL/RLDICL/RLDICR definition uses as 'MB'.

It end up by generatint the 'rldicl' enconding at 
'lib/Target/PowerPC/PPCGenMCCodeEmitter.inc' to use the fourth argument as the
third. The patch changes it by adjusting to use the fourth argument as
intended.

Fixes PR14180.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166770 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-26 12:09:58 +00:00
Adhemerval Zanella
18560fae0b This patch fixes the MC object emission of 'nop' for external function calls
and also fixes the R_PPC64_TOC16 and R_PPC64_TOC16_DS relocation offset.
The 'nop' is needed so a restore TOC instruction (ld r2,40(r1)) can be placed
by the linker to correct restore the TOC of previous function.

Current code has two issues: it defines in PPCInstr64Bit.td file a LDinto_toc
and LDtoc_restore as a DSForm_1 with DS_RA=0 where it should be
DS=2 (the 8 bytes displacement of the TOC saving). It also wrongly emits a
MC intruction using an uint32_t value while the PPC::BL8_NOP_ELF
and PPC::BLA8_NOP_ELF are both uint64_t (because of the following 'nop').

This patch corrects the remaining ExecutionEngine using MCJIT:

ExecutionEngine/2002-12-16-ArgTest.ll
ExecutionEngine/2003-05-07-ArgumentTest.ll
ExecutionEngine/2005-12-02-TailCallBug.ll
ExecutionEngine/hello.ll
ExecutionEngine/hello2.ll
ExecutionEngine/test-call.ll



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166682 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-25 14:29:13 +00:00
Will Schmidt
916381569a - add tokens to PPCInstrInfo.td and PPCInstr64Bit.td to resolve
"Instruction 'foo' has no tokens" errors during llvm-tblgen
-gen-asm-matcher attempts.  At this time, the added
tokens are "#comment" style rather than the actual mnemonic.  This will
be revisited once the rest of the base asmparser bits get straightened
out for ppc64-elf-linux.




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165237 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-04 18:14:28 +00:00
Hal Finkel
c10d5e9dae Move the PPC TOC defs into the PPC64 InstrInfo file.
Since TOC is just defined for PPC64, move its definition to PPC64 td file.

Patch by Adhemerval Zanella.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163234 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-05 19:22:27 +00:00
Hal Finkel
8dc440a46a Split several PPC instruction classes.
Slight reorganisation of PPC instruction classes for scheduling. No
functionality change for existing subtargets.
 - Clearly separate load/store-with-update instructions from regular loads and stores.
 - Split IntRotateD -> IntRotateD and IntRotateDI
 - Split out fsub and fadd from FPGeneral -> FPAddSub
 - Update existing itineraries

Patch by Tobias von Koch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162729 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-28 02:49:14 +00:00
Hal Finkel
f3c3828e57 Allow remat of LI on PPC.
Allow load-immediates to be rematerialised in the register coalescer for
PPC. This makes test/CodeGen/PowerPC/big-endian-formal-args.ll fail,
because it relies on a register move getting emitted. The immediate load is
equivalent, so change this test case.

Patch by Tobias von Koch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162727 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-28 02:10:33 +00:00