The optimization for locally used allocas was not safe for allocas that
were read before they were written.  This change disables that optimization
in that case.

llvm-svn: 22318

llvm-svn: 22263

This fixes PR584 and Transforms/SimplifyCFG/2005-06-16-PHICrash.ll

llvm-svn: 22232

llvm-svn: 22158

a call.  This fixes Prolangs-C++/deriv2, kimwitu++, and Misc-C++/bigfib
on X86 with -enable-x86-fastcc.

llvm-svn: 22023

turning calls into invokes

llvm-svn: 21797

not change code after testing it without retesting!

llvm-svn: 21741

llvm-svn: 21736

llvm-svn: 21719

are moved to simplify-libcalls pass.

llvm-svn: 21614

  sinh, cosh, etc.
* Make the name comparisons for the fp libcalls a little more efficient by
  switching on the first character of the name before doing comparisons.

llvm-svn: 21611

llvm-svn: 21480

llvm-svn: 21427

llvm-svn: 21393

convert this:

        %tmp.1 = seteq int %i, 0                ; <bool> [#uses=1]
        br bool %tmp.1, label %shortcirc_done, label %shortcirc_next

shortcirc_next:         ; preds = %entry
        %tmp.4 = seteq int %j, 0                ; <bool> [#uses=1]
        br label %shortcirc_done

shortcirc_done:         ; preds = %shortcirc_next, %entry
        %shortcirc_val = phi bool [ %tmp.4, %shortcirc_next ], [ true, %entry ]         ; <bool> [#uses=1]

to this:
        %tmp.1 = seteq int %i, 0                ; <bool> [#uses=1]
        %tmp.4 = seteq int %j, 0                ; <bool> [#uses=1]
        %shortcirc_val = select bool %tmp.1, bool true, bool %tmp.4             ; <bool> [#uses=1]

... which is later simplified by instcombine into an or.

llvm-svn: 21388

llvm-svn: 21253

Bill Wendling!!

llvm-svn: 20649

using Function::arg_{iterator|begin|end}.  Likewise Module::g* -> Module::global_*.

This patch is contributed by Gabor Greif, thanks!

llvm-svn: 20597

llvm-svn: 20463

llvm-svn: 20343

llvm-svn: 20334

This does a simple form of "jump threading", which eliminates CFG edges that
are provably dead.  This triggers 90 times in the external tests, and
eliminating CFG edges is always always a good thing! :)

llvm-svn: 20300

llvm-svn: 19898

SimplifyCFG is one of those passes that we use for final cleanup: it should
not rely on other passes to clean up its garbage.  This fixes the "why are
trivially dead setcc's in the output of gccas" problem.

llvm-svn: 19212

llvm-svn: 18799

and the failure on make_dparser last night.

llvm-svn: 18766

llvm-svn: 18381

This only fails on darwin or on X86 under valgrind.

llvm-svn: 18377

llvm-svn: 18369

  if (x) {
    code
    ...
  } else {
    code
    ...
  }

Turn it into:

  code
  if (x) {
    ...
  } else {
    ...
  }

This reduces code size and in some common cases allows us to completely
eliminate the conditional.  This turns several if/then/else blocks in loops
into straightline code in 179.art, turning the loops into single basic blocks
(good for modsched even!).

Maybe now brg will leave me alone ;-)

llvm-svn: 18366

llvm-svn: 18028

llvm-svn: 17699

instructions, setting DefBlock to a block it did not have dom info for.

llvm-svn: 17697

This speeds up simplifycfg on this program, from 44.87s to 0.29s (with
a profiled build):

 #define CL0(a) case a: goto c;
 #define CL1(a) CL0(a##0) CL0(a##1) CL0(a##2) CL0(a##3) CL0(a##4) CL0(a##5) \
 CL0(a##6) CL0(a##7) CL0(a##8) CL0(a##9)
 #define CL2(a) CL1(a##0) CL1(a##1) CL1(a##2) CL1(a##3) CL1(a##4) CL1(a##5) \
 CL1(a##6) CL1(a##7) CL1(a##8) CL1(a##9)
 #define CL3(a) CL2(a##0) CL2(a##1) CL2(a##2) CL2(a##3) CL2(a##4) CL2(a##5) \
 CL2(a##6) CL2(a##7) CL2(a##8) CL2(a##9)
 #define CL4(a) CL3(a##0) CL3(a##1) CL3(a##2) CL3(a##3) CL3(a##4) CL3(a##5) \
 CL3(a##6) CL3(a##7) CL3(a##8) CL3(a##9)

 void f();

 void a() {
     int b;
  c: switch (b) {
         CL4(1)
     }
 }

This testcase is contrived to expose N^2 behavior, but this patch should speedup
simplifycfg on any programs that use large switch statements.  This testcase
comes from GCC PR17895.

llvm-svn: 17389

llvm-svn: 17286

llvm-svn: 17163

llvm-svn: 17155

llvm-svn: 17136

Patch contributed by Morten Ofstad. Thanks Morten!

llvm-svn: 17123

Simplify code by simplifying terminators that branch to blocks that start
with an unreachable instruction.

llvm-svn: 17116