llvm-svn: 132108

rdar://problem/6920088

llvm-svn: 132105

  non-zero.
- Teach X86 cmov optimization to eliminate the cmov from ctlz, cttz extension
  when the source of X86ISD::BSR / X86ISD::BSF is proven to be non-zero.

rdar://9490949

llvm-svn: 131948

llvm-svn: 131709

llvm-svn: 131708

Fixes rdar://9218925
Fixes PR9601

llvm-svn: 131682

llvm-svn: 131664

Enables vararg functions that pass all arguments via registers to be optimized into tail-calls when possible.

llvm-svn: 131560

llvm-svn: 131471

llvm-svn: 131469

passed as the fifth parameter, insure it's passed correctly (in R9).
rdar://problem/6920088

llvm-svn: 131467

Fix a bug in PerformEXTRACT_VECTOR_ELTCombine. The code created an ADD SDNode
with two different types, in cases where the index and the ptr had different
types.

llvm-svn: 131461

llvm-svn: 131424

Add custom lowering of X86 vector SRA/SRL/SHL when the shift amount is a splat vector.

llvm-svn: 131179

llvm-svn: 131012

triple component.

llvm-svn: 129838

llvm-svn: 129813

Luis Felipe Strano Moraes!

llvm-svn: 129558

llvm-svn: 128586

llvm-svn: 128338

FIXME: Some cleanups would be needed.
llvm-svn: 128206

I'm backing this out for the second time. It was supposed to be fixed by r128164, but the mingw self-host must be defeating the fix.

llvm-svn: 128181

(target-specific branchless method for double-width relational comparisons on x86)

llvm-svn: 128175

Re-apply r127953 with fixes: eliminate empty return block if it has no predecessors; update dominator tree if cfg is modified.

llvm-svn: 127981

to canonicalize IR", it broke a lot of things.

llvm-svn: 127954

to have single return block (at least getting there) for optimizations. This
is general goodness but it would prevent some tailcall optimizations.
One specific case is code like this:
int f1(void);
int f2(void);
int f3(void);
int f4(void);
int f5(void);
int f6(void);
int foo(int x) {
  switch(x) {
  case 1: return f1();
  case 2: return f2();
  case 3: return f3();
  case 4: return f4();
  case 5: return f5();
  case 6: return f6();
  }
}

=>
LBB0_2:                                 ## %sw.bb
  callq   _f1
  popq    %rbp
  ret
LBB0_3:                                 ## %sw.bb1
  callq   _f2
  popq    %rbp
  ret
LBB0_4:                                 ## %sw.bb3
  callq   _f3
  popq    %rbp
  ret

This patch teaches codegenprep to duplicate returns when the return value
is a phi and where the phi operands are produced by tail calls followed by
an unconditional branch:

sw.bb7:                                           ; preds = %entry
  %call8 = tail call i32 @f5() nounwind
  br label %return
sw.bb9:                                           ; preds = %entry
  %call10 = tail call i32 @f6() nounwind
  br label %return
return:
  %retval.0 = phi i32 [ %call10, %sw.bb9 ], [ %call8, %sw.bb7 ], ... [ 0, %entry ]
  ret i32 %retval.0

This allows codegen to generate better code like this:

LBB0_2:                                 ## %sw.bb
        jmp     _f1                     ## TAILCALL
LBB0_3:                                 ## %sw.bb1
        jmp     _f2                     ## TAILCALL
LBB0_4:                                 ## %sw.bb3
        jmp     _f3                     ## TAILCALL

rdar://9147433

llvm-svn: 127953

not have native support for this operation (such as X86).
The legalized code uses two vector INT_TO_FP operations and is faster
than scalarizing.

llvm-svn: 127951

llvm-svn: 127909

comparisons on x86.  Essentially, the way this works is that SUB+SBB sets
the relevant flags the same way a double-width CMP would.

This is a substantial improvement over the generic lowering in LLVM. The output
is also shorter than the gcc-generated output; I haven't done any detailed
benchmarking, though.

llvm-svn: 127852

llvm-svn: 127809

llvm-svn: 127807

rather than an int. Thankfully, this only causes LLVM to miss optimizations, not
generate incorrect code.

This just fixes the zext at the return. We still insert an i32 ZextAssert when
reading a function's arguments, but it is followed by a truncate and another i8
ZextAssert so it is not optimized.

llvm-svn: 127766

corresponding testcases back to the previous versions.

Fixes some performance regressions only seen on 32-bit.

llvm-svn: 127441

llvm-svn: 127382

llvm-svn: 127359

llvm-svn: 127328

Found by inspection.

llvm-svn: 127247

testcases accordingly. Some are currently xfailed and will be filed
as bugs to be fixed or understood.

Performance results:

roughly neutral on SPEC
some micro benchmarks in the llvm suite are up between 100 and 150%, only
a pair of regressions that are due to be investigated

john-the-ripper saw:
10% improvement in traditional DES
8% improvement in BSDI DES
59% improvement in FreeBSD MD5
67% improvement in OpenBSD Blowfish
14% improvement in LM DES

Small compile time impact.

llvm-svn: 127208

llvm-svn: 127175

regs. This is the only change in this checkin that may affects the
default scheduler. With better register tracking and heuristics, it
doesn't make sense to artificially lower the register limit so much.

Added -sched-high-latency-cycles and X86InstrInfo::isHighLatencyDef to
give the scheduler a way to account for div and sqrt on targets that
don't have an itinerary. It is currently defaults to 10 (the actual
number doesn't matter much), but only takes effect on non-default
schedulers: list-hybrid and list-ilp.

Added several heuristics that can be individually disabled for the
non-default sched=list-ilp mode. This helps us determine how much
better we can do on a given benchmark than the default
scheduler. Certain compute intensive loops run much faster in this
mode with the right set of heuristics, and it doesn't seem to have
much negative impact elsewhere. Not all of the heuristics are needed,
but we still need to experiment to decide which should be disabled by
default for sched=list-ilp.

llvm-svn: 127067