- Change register allocation hint to a pair of unsigned integers. The hint type is zero (which means prefer the register specified as second part of the pair) or entirely target dependent.
- Allow targets to specify alternative register allocation orders based on allocation hint.

Part 2.
- Use the register allocation hint system to implement more aggressive load / store multiple formation.
- Aggressively form LDRD / STRD. These are formed *before* register allocation. It has to be done this way to shorten live interval of base and offset registers. e.g.
v1025 = LDR v1024, 0
v1026 = LDR v1024, 0
=>
v1025,v1026 = LDRD v1024, 0

If this transformation isn't done before allocation, v1024 will overlap v1025 which means it more difficult to allocate a register pair.

- Even with the register allocation hint, it may not be possible to get the desired allocation. In that case, the post-allocation load / store multiple pass must fix the ldrd / strd instructions. They can either become ldm / stm instructions or back to a pair of ldr / str instructions.

This is work in progress, not yet enabled.

llvm-svn: 73381

llvm-svn: 73373

llvm-svn: 73372

llvm-svn: 73366

llvm-svn: 73362

Introduce new BinaryObject (blob) class, ELF Writer modified to use it. BinaryObject.h by Aaron Gray

llvm-svn: 73333

The subprogram descriptor for a function may be missing (llvm-ld linking two static functions with same name), so pick up the compilation unit for the function from the first valid debug loc of its instructions.
This patch also emits debug info for structure (aggregate types in 
general) types.

llvm-svn: 73295

consecutive addresses togther. This makes it easier for the post-allocation pass
to form ldm / stm.

This is step 1. We are still missing a lot of ldm / stm opportunities because
of register allocation are not done in the desired order. More enhancements
coming.

llvm-svn: 73291

llvm-svn: 73252

out of sync with regular cc.

The only difference between the tail call cc and the normal
cc was that one parameter register - R9 - was reserved for
calling functions through a function pointer. After time the
tail call cc has gotten out of sync with the regular cc. 

We can use R11 which is also caller saved but not used as
parameter register for potential function pointers and
remove the special tail call cc on x86-64.

llvm-svn: 73233

add a few suggestions from looking at some assembly code.

llvm-svn: 73210

llvm-svn: 73209

Emission for globals, using the correct data sections
Function alignment can be computed for each target using TargetELFWriterInfo
Some small fixes

llvm-svn: 73201

llvm-svn: 73194

llvm-svn: 73185

llvm-svn: 73184

llvm-svn: 73152

change.

llvm-svn: 73143

PIC16 emits auto variables as globals. When optimizer removes a function entierly by estimating its side effects on globals, those globals(autos) without a function were not being printed by the Asm printer.

llvm-svn: 73135

llvm-svn: 73098

llvm-svn: 73097

ABI. The missing piece is support for putting "homogeneous aggregates"
into registers.

Patch by Sandeep Patel!

llvm-svn: 73095

llvm-svn: 73085

llvm-svn: 73080

llvm-svn: 73075

llvm-svn: 73017

on x86 to handle more cases.  Fix a bug in said code that would cause it 
to read past the end of an object.  Rewrite the code in 
SelectionDAGLegalize::ExpandBUILD_VECTOR to be a bit more general. 
Remove PerformBuildVectorCombine, which is no longer necessary with 
these changes.  In addition to simplifying the code, with this change, 
we can now catch a few more cases of consecutive loads.

llvm-svn: 73012

instructions.

llvm-svn: 73009

llvm-svn: 72991

nodes for vectors with an i16 element type.  Add an optimization for 
building a vector which is all zeros/undef except for the bottom 
element, where the bottom element is an i8 or i16.

llvm-svn: 72988

llvm-svn: 72987

llvm-svn: 72986

llvm-svn: 72985

conversions for x86, like <2 x i32> -> <2 x float> and <4 x i16> -> 
<4 x float>.

llvm-svn: 72983

llvm-svn: 72969

Update code generator to use this attribute and remove NoImplicitFloat target option.
Update llc to set this attribute when -no-implicit-float command line option is used.

llvm-svn: 72959

build vectors with i64 elements will only appear on 32b x86 before legalize.
Since vector widening occurs during legalize, and produces i64 build_vector 
elements, the dag combiner is never run on these before legalize splits them
into 32b elements.

Teach the build_vector dag combine in x86 back end to recognize consecutive 
loads producing the low part of the vector.

Convert the two uses of TLI's consecutive load recognizer to pass LoadSDNodes
since that was required implicitly.

Add a testcase for the transform.

Old:
	subl	$28, %esp
	movl	32(%esp), %eax
	movl	4(%eax), %ecx
	movl	%ecx, 4(%esp)
	movl	(%eax), %eax
	movl	%eax, (%esp)
	movaps	(%esp), %xmm0
	pmovzxwd	%xmm0, %xmm0
	movl	36(%esp), %eax
	movaps	%xmm0, (%eax)
	addl	$28, %esp
	ret

New:
	movl	4(%esp), %eax
	pmovzxwd	(%eax), %xmm0
	movl	8(%esp), %eax
	movaps	%xmm0, (%eax)
	ret

llvm-svn: 72957

Changing allocation ordering from r3 ... r0 back to r0 ... r3. The order change no longer make sense after the coalescing changes we have made since then.

llvm-svn: 72955

llvm-svn: 72954

llvm-svn: 72952