Sam Panzer, author of loop convert, provided a list of limitations of the tool
to be documented. (Thanks Sam!)
The transform's limitations are now documented in the existing user doc.
Included are examples of the cases where the tool may change semantics.
Author: Jack Yang <jack.yang@intel.com>
llvm-svn: 178034
The OptimizeIntToFloatBitCast converts shift-truncate sequences
into extractelement operations. The computation of the element
index to be used in the resulting operation is currently only
correct for little-endian targets.
This commit fixes the element index computation to be correct
for big-endian targets as well. If the target byte order is
unknown, the optimization cannot be performed at all.
llvm-svn: 178031
This reverts commit r177968. It is causing failures in a local build bot.
"fatal error: error in backend: Expected a variant SchedClass"
Original commit message:
Move the CortexA9 resources into the CortexA9 SchedModel namespace. Define
resource mappings under the CortexA9 SchedModel. Define resources and mappings
for the SwiftModel.
llvm-svn: 178028
Restore the EXEC mask early, otherwise a copy might end up not beeing executed.
Candidate for the mesa stable branch.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Tested-by: Michel Dänzer <michel.daenzer@amd.com>
llvm-svn: 178018
If PC or SP is the destination, the disassembler erroneously failed with the
invalid encoding, despite the manual saying that both are fine.
This patch addresses failure to decode encoding T4 of LDR (A8.8.62) which is a
postindexed load, where the offset 0xc is applied to SP after the load occurs.
llvm-svn: 178017
CalleeWithThisReturn can be left initialized if HasThisReturn() is false.
This change reverses the order of checks in EmitFunctionEpilog such that
CalleeWithThisReturn is only examined when it has a meaningful value.
Found with MemorySanitizer.
llvm-svn: 178015
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.
llvm-svn: 178008
MCTargetDesc/PPCMCCodeEmitter.cpp current has code like:
if (isSVR4ABI() && is64BitMode())
Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_toc16));
else
Fixups.push_back(MCFixup::Create(0, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_lo16));
This is a problem for the asm parser, since it requires knowledge of
the ABI / 64-bit mode to be set up. However, more fundamentally,
at this point we shouldn't make such distinctions anyway; in an assembler
file, it always ought to be possible to e.g. generate TOC relocations even
when the main ABI is one that doesn't use TOC.
Fortunately, this is actually completely unnecessary; that code was added
to decide whether to generate TOC relocations, but that information is in
fact already encoded in the VariantKind of the underlying symbol.
This commit therefore merges those fixup types into one, and then decides
which relocation to use based on the VariantKind.
No changes in generated code.
llvm-svn: 178007
As part of the the sequence generated to implement long double -> int
conversions, we need to perform an FADD in round-to-zero mode. This is
problematical since the FPSCR is not at all modeled at the SelectionDAG
level, and thus there is a risk of getting floating point instructions
generated out of sequence with the instructions to modify FPSCR.
The current code handles this by somewhat "special" patterns that in part
have dummy operands, and/or duplicate existing instructions, making them
awkward to handle in the asm parser.
This commit changes this by leaving the "FADD in round-to-zero mode"
as an atomic operation on the SelectionDAG level, and only split it up into
real instructions at the MI level (via custom inserter). Since at *this*
level the FPSCR *is* modeled (via the "RM" hard register), much of the
"special" stuff can just go away, and the resulting patterns can be used by
the asm parser.
No significant change in generated code expected.
llvm-svn: 178006
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.
llvm-svn: 178005
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.
llvm-svn: 178004
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.
llvm-svn: 178003
The BLR pattern cannot be recognized by the asm parser in its current form.
This complexity is due to an apparent attempt to enable conditional BLR
variants. However, none of those can ever be generated by current code;
the pattern is only ever created using the default "pred" operand.
To simplify the pattern and allow it to be recognized by the parser,
this commit removes those attempts at conditional BLR support.
When we later come back to actually add real conditional BLR, this
should probably be done via a fully generic conditional branch pattern.
No change in generated code.
llvm-svn: 178002
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.
llvm-svn: 178001
Use a MapVector on types where the iteration order matters.
Otherwise we doesn't always produce a deterministic output.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
llvm-svn: 177999
that work on the LLVMBuild based dependency specification didn't
actually work, we just now maintain dependencies in *3* places instead
of 2. Yay.
There may still be some missing dependencies, I'm still sifting through
the bots and my builds, but this is a step in the right direction.
llvm-svn: 177988
Fixes PR15570: SEGV: SCEV back-edge info invalid after dead code removal.
Indvars creates a SCEV expression for the loop's back edge taken
count, then determines that the comparison is always true and
removes it.
When loop-unroll asks for the expression, it contains a NULL
SCEVUnknkown (as a CallbackVH).
forgetMemoizedResults should invalidate the loop back edges expression.
llvm-svn: 177986
Greg Clayton