Add a bit IsUndef to MachineOperand. This indicates the def / use register operand is defined by an implicit_def. That means it can def / use any register and passes (e.g. register scavenger) can feel free to ignore them.

The register allocator, when it allocates a register to a virtual register defined by an implicit_def, can allocate any physical register without worrying about overlapping live ranges. It should mark all of operands of the said virtual register so later passes will do the right thing.

This is not the best solution. But it should be a lot less fragile to having the scavenger try to track what is defined by implicit_def.

llvm-svn: 74518

globals.  This implements remat-constant.ll even without aggressive-remat.

llvm-svn: 74373

implementation primarily differs from the former in that the asmprinter
doesn't make a zillion decisions about whether or not something will be
RIP relative or not.  Instead, those decisions are made by isel lowering
and propagated through to the asm printer.  To achieve this, we:

1. Represent RIP relative addresses by setting the base of the X86 addr
   mode to X86::RIP.
2. When ISel Lowering decides that it is safe to use RIP, it lowers to
   X86ISD::WrapperRIP.  When it is unsafe to use RIP, it lowers to
   X86ISD::Wrapper as before.
3. This removes isRIPRel from X86ISelAddressMode, representing it with
   a basereg of RIP instead.
4. The addressing mode matching logic in isel is greatly simplified.
5. The asmprinter is greatly simplified, notably the "NotRIPRel" predicate
   passed through various printoperand routines is gone now.
6. The various symbol printing routines in asmprinter now no longer infer
   when to emit (%rip), they just print the symbol.

I think this is a big improvement over the previous situation.  It does have
two small caveats though: 1. I implemented a horrible "no-rip" modifier for
the inline asm "P" constraint modifier.  This is a short term hack, there is
a much better, but more involved, solution.  2. I had to xfail an 
-aggressive-remat testcase because it isn't handling the use of RIP in the
constant-pool reading instruction.  This specific test is easy to fix without
-aggressive-remat, which I intend to do next.

llvm-svn: 74372

from the asmprinter.

llvm-svn: 74184

llvm-svn: 74183

the code tried to use "push", which doesn't exist for XMM registers.)

llvm-svn: 72836

decoding. Essentially, they both map to the same column in the "opcode
extensions for one- and two-byte opcodes" table in the x86 manual. The RawFrm
complicates decoding this.

Instead, use opcode 0x01, prefix 0x01, and form MRM1r. Then have the code
emitter special case these, a la [SML]FENCE.

llvm-svn: 72556

booleans. This gives a better indication of what the "addReg()" is
doing. Remembering what all of those booleans mean isn't easy, especially if you
aren't spending all of your time in that code.

I took Jakob's suggestion and made it illegal to pass in "true" for the
flag. This should hopefully prevent any unintended misuse of this (by reverting
to the old way of using addReg()).

llvm-svn: 71722

llvm-svn: 71520

Optimize code placement in loop to eliminate unconditional branches or move unconditional branch to the outside of the loop. e.g.

///       A:                                                                                                                                                                 
///       ...                                                                                                                                                                
///       <fallthrough to B>                                                                                                                                                 
///                                                                                                                                                                          
///       B:  --> loop header                                                                                                                                                
///       ...                                                                                                                                                                
///       jcc <cond> C, [exit]                                                                                                                                               
///                                                                                                                                                                          
///       C:                                                                                                                                                                 
///       ...                                                                                                                                                                
///       jmp B                                                                                                                                                              
///                                                                                                                                                                          
/// ==>                                                                                                                                                                      
///                                                                                                                                                                          
///       A:                                                                                                                                                                 
///       ...                                                                                                                                                                
///       jmp B                                                                                                                                                              
///                                                                                                                                                                          
///       C:  --> new loop header                                                                                                                                            
///       ...                                                                                                                                                                
///       <fallthough to B>                                                                                                                                                  
///                                                                                                                                                                          
///       B:                                                                                                                                                                 
///       ...                                                                                                                                                                
///       jcc <cond> C, [exit] 

llvm-svn: 71209

Revert part of 70929 that has to do with determining whether a SIB byte is needed. It causes a lot of x86_64 JIT failures.

llvm-svn: 70986

- Synchronize instruction length computation code in X86InstrInfo with code in X86CodeEmitter.cpp
Patch by Zoltan Varga.

llvm-svn: 70929

to precisely describe the h-register subreg register classes.
Thanks to Jakob Stoklund Olesen for spotting this and for the
initial patch!

Also, make getStoreRegOpcode and getLoadRegOpcode aware of the
needs of h registers.

llvm-svn: 70211

GR32_ABCD, and GR64_ABCD, respectively, to help describe them.

llvm-svn: 70210

This makes the extra copyRegToReg calls in ScheduleDAGSDNodesEmit.cpp
unnecessary. Derived from a patch by Jakob Stoklund Olesen.

llvm-svn: 69635

llvm-svn: 69417

llvm-svn: 69394

llvm-svn: 69347

matter, because this instruction isn't generated until after
things that care.

llvm-svn: 69336

present, but it's inconsistent.

llvm-svn: 69335

llvm-svn: 69204

llvm-svn: 69203

either the source or destination is a physical h register.

This fixes sqlite3 with the post-RA scheduler enabled.

llvm-svn: 69111

 - Add patterns for h-register extract, which avoids a shift and mask,
   and in some cases a temporary register.
 - Add address-mode matching for turning (X>>(8-n))&(255<<n), where
   n is a valid address-mode scale value, into an h-register extract
   and a scaled-offset address.
 - Replace X86's MOV32to32_ and related instructions with the new
   target-independent COPY_TO_SUBREG instruction.

On x86-64 there are complicated constraints on h registers, and
CodeGen doesn't currently provide a high-level way to express all of them,
so they are handled with a bunch of special code. This code currently only
supports extracts where the result is used by a zero-extend or a store,
though these are fairly common.

These transformations are not always beneficial; since there are only
4 h registers, they sometimes require extra move instructions, and
this sometimes increases register pressure because it can force out
values that would otherwise be in one of those registers. However,
this appears to be relatively uncommon.

llvm-svn: 68962

This unbreaks the JIT on x86-64.

llvm-svn: 68948

llvm-svn: 68690

Tested by bootstrapping llvm-gcc and using that to build llvm.

llvm-svn: 68645

builds.

--- Reverse-merging (from foreign repository) r68552 into '.':
U    test/CodeGen/X86/tls8.ll
U    test/CodeGen/X86/tls10.ll
U    test/CodeGen/X86/tls2.ll
U    test/CodeGen/X86/tls6.ll
U    lib/Target/X86/X86Instr64bit.td
U    lib/Target/X86/X86InstrSSE.td
U    lib/Target/X86/X86InstrInfo.td
U    lib/Target/X86/X86RegisterInfo.cpp
U    lib/Target/X86/X86ISelLowering.cpp
U    lib/Target/X86/X86CodeEmitter.cpp
U    lib/Target/X86/X86FastISel.cpp
U    lib/Target/X86/X86InstrInfo.h
U    lib/Target/X86/X86ISelDAGToDAG.cpp
U    lib/Target/X86/AsmPrinter/X86ATTAsmPrinter.cpp
U    lib/Target/X86/AsmPrinter/X86IntelAsmPrinter.cpp
U    lib/Target/X86/AsmPrinter/X86ATTAsmPrinter.h
U    lib/Target/X86/AsmPrinter/X86IntelAsmPrinter.h
U    lib/Target/X86/X86ISelLowering.h
U    lib/Target/X86/X86InstrInfo.cpp
U    lib/Target/X86/X86InstrBuilder.h
U    lib/Target/X86/X86RegisterInfo.td

llvm-svn: 68560

This introduces a small regression on the generated code
quality in the case we are just computing addresses, not
loading values.

Will work on it and on X86-64 support.

llvm-svn: 68552

llvm-svn: 67949

of operands in an address in so many places.

llvm-svn: 67945

llvm-svn: 67848

Fix some significant problems with constant pools that resulted in unnecessary paddings between constant pool entries, larger than necessary alignments (e.g. 8 byte alignment for .literal4 sections), and potentially other issues.

1. ConstantPoolSDNode alignment field is log2 value of the alignment requirement. This is not consistent with other SDNode variants.
2. MachineConstantPool alignment field is also a log2 value.
3. However, some places are creating ConstantPoolSDNode with alignment value rather than log2 values. This creates entries with artificially large alignments, e.g. 256 for SSE vector values.
4. Constant pool entry offsets are computed when they are created. However, asm printer group them by sections. That means the offsets are no longer valid. However, asm printer uses them to determine size of padding between entries.
5. Asm printer uses expensive data structure multimap to track constant pool entries by sections.
6. Asm printer iterate over SmallPtrSet when it's emitting constant pool entries. This is non-deterministic.


Solutions:
1. ConstantPoolSDNode alignment field is changed to keep non-log2 value.
2. MachineConstantPool alignment field is also changed to keep non-log2 value.
3. Functions that create ConstantPool nodes are passing in non-log2 alignments.
4. MachineConstantPoolEntry no longer keeps an offset field. It's replaced with an alignment field. Offsets are not computed when constant pool entries are created. They are computed on the fly in asm printer and JIT.
5. Asm printer uses cheaper data structure to group constant pool entries.
6. Asm printer compute entry offsets after grouping is done.
7. Change JIT code to compute entry offsets on the fly.

llvm-svn: 66875

llvm-svn: 66057

of MachineInstr def operands must be subtracted out. This bug
was uncovered by the recent x86 EFLAGS optimization. Before
that, the only instructions that ever needed unfolding were
things like CMP32rm, where NumDefs is zero.

llvm-svn: 66056

Do not consider MMX_MOVD64rr a move instructions. The source register is in GR32, the destination is VR64. They are not compatible.

llvm-svn: 65273

llvm-svn: 64891

There were some that might even matter in X86FastISel.

llvm-svn: 64437

Modify callers.

llvm-svn: 64409

llvm-svn: 64329