llvm-svn: 68254

llvm-svn: 68253

 - The code is silly, I'm just amusing myself. Rewrite to be efficient
   if you like. :)

Also, if you wish to debate the proper names of the triple components
I'm all ears.

llvm-svn: 68252

llvm-svn: 68250

llvm-svn: 68249

llvm-svn: 68248

llvm-svn: 68246

llvm-svn: 68243

Patch by Kevin Fan!

llvm-svn: 68239

llvm-svn: 68229

is appropriate. This helps visually differentiate host-oriented
calculations from target-oriented calculations.

llvm-svn: 68227

llvm-svn: 68222

less ambiguous and less C-specific.

llvm-svn: 68219

assembly.

llvm-svn: 68218

  Applications/Burg/burg
  Applications/ClamAV/clamscan
and many other tests.

llvm-svn: 68211

llvm-svn: 68209

llvm-svn: 68206

Based on a patch by Nicolas Trangez on the unladen-swallow mailing list!

llvm-svn: 68187

llvm-svn: 68175

llvm-svn: 68173

llvm-svn: 68172

llvm-svn: 68167

* Simplified if statement

llvm-svn: 68163

llvm-svn: 68159

llvm-svn: 68158

it be an LLVM IR User object.

llvm-svn: 68156

if it dangles.

llvm-svn: 68150

which are effectively smart pointers to Value*'s.  They are both very light
weight and simple, and react to values being destroyed or being RAUW'd.

WeakVN does a best effort to follow a value around, including through RAUW 
operations and will get nulled out of the value is destroyed.  This is useful
for the eventual "metadata that references a value" work, because it is a
reference to a value that does not show up on its use_* list.

AssertingVH is a pointer that compiles down to a dumb raw pointer when 
assertions are disabled.  When enabled, it emits an assertion if the 
pointed-to value is destroyed while it is still being referenced.  This
is very useful for Maps and other things, and should have caught the recent
bugs in CallGraph and Reassociate, for example.

llvm-svn: 68149

llvm-svn: 68147

llvm-svn: 68145

Throttle back "fold select into operand" transformation. InstCombine should not generate selects of two constants unless they are selects of 0 and 1.

e.g.
define i32 @t1(i32 %c, i32 %x) nounwind {
       %t1 = icmp eq i32 %c, 0
       %t2 = lshr i32 %x, 18
       %t3 = select i1 %t1, i32 %t2, i32 %x
       ret i32 %t3
}

was turned into

define i32 @t2(i32 %c, i32 %x) nounwind {
       %t1 = icmp eq i32 %c, 0
       %t2 = select i1 %t1, i32 18, i32 0
       %t3 = lshr i32 %x, %t2
       ret i32 %t3
}

For most targets, that means materializing two constants and then a select. e.g. On x86-64

movl    %esi, %eax
shrl    $18, %eax
testl   %edi, %edi
cmovne  %esi, %eax
ret

=>

xorl    %eax, %eax
testl   %edi, %edi
movl    $18, %ecx
cmovne  %eax, %ecx
movl    %esi, %eax
shrl    %cl, %eax
ret

Also, the optimizer and codegen can reason about shl / and / add, etc. by a constant. This optimization will hinder optimizations using ComputeMaskedBits.

llvm-svn: 68142

llvm-svn: 68134

llvm-svn: 68133

entered via fall-through. Don't miss fallthroughs from blocks
terminated by conditional branches. Also, move
isOnlyReachableByFallthrough out of line.

llvm-svn: 68129

Does not work well on 32 bit targets. Bug reported by Albert Graef.

This patch also adds new "-Wllc,option" syntax to pass options to llc.

llvm-svn: 68127

llvm-svn: 68126

possible to run the tests with -asm-verbose defaulting
to false.

llvm-svn: 68124

Patch by Jay Foad.

llvm-svn: 68120

llvm::sys::getOS{Name,Version}.

Right now the implementation just derives from LLVM_HOSTTRIPLE (which
is wrong, but it doesn't look like we have a define for the target
triple). Ideally this routine would actually be able to compute the
triple for targets we care about.

llvm-svn: 68118

llvm-svn: 68113