not define a value that is used outside of it's block. This catches many
more simplifications, e.g. 854 in 176.gcc, 137 in vpr, etc.
This implements branch-phi-thread.ll:test3.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23397 91177308-0d34-0410-b5e6-96231b3b80d8
control across branches with determined outcomes. More generality to follow.
This triggers a couple thousand times in specint.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23391 91177308-0d34-0410-b5e6-96231b3b80d8
consideration the case where a reference in an unreachable block could
occur. This fixes Transforms/SimplifyCFG/2005-08-01-PHIUpdateFail.ll,
something I ran into while bugpoint'ing another pass.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22584 91177308-0d34-0410-b5e6-96231b3b80d8
a call. This fixes Prolangs-C++/deriv2, kimwitu++, and Misc-C++/bigfib
on X86 with -enable-x86-fastcc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22023 91177308-0d34-0410-b5e6-96231b3b80d8
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! :)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@20300 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@19212 91177308-0d34-0410-b5e6-96231b3b80d8
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 ;-)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@18366 91177308-0d34-0410-b5e6-96231b3b80d8
Simplify code by simplifying terminators that branch to blocks that start
with an unreachable instruction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17116 91177308-0d34-0410-b5e6-96231b3b80d8
nodes unless we KNOW that we are able to promote all of them.
This fixes: test/Regression/Transforms/SimplifyCFG/PhiNoEliminate.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16973 91177308-0d34-0410-b5e6-96231b3b80d8
Move include/Config and include/Support into include/llvm/Config,
include/llvm/ADT and include/llvm/Support. From here on out, all LLVM
public header files must be under include/llvm/.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16137 91177308-0d34-0410-b5e6-96231b3b80d8
since May 1st. In this code, the pred iterator was being invalidated sometimes
causing the wrong entries to be added to PHI nodes.
The fix for this is to defererence and safe the *PI value before we hack on
branch instructions, which changes use/def chains, which SOMETIMES invalidates
the iterator.
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Fix another non-deterministic behavior, this one should actually speed up the
code though as it was doing silly things.
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nondeterministic results that depend on where these objects land in memory.
Instead, sort by the value of the constant, which is stable.
Before this patch, the -simplifycfg pass run from two different compilers
could cause different code to be generated, though it was semantically the
same:
@@ -12258,8 +12258,8 @@
%s_addr.1 = phi sbyte* [ %s, %entry ], [ %inc.0, %no_exit ] ; <sbyte*> [#uses=5]
%tmp.1 = load sbyte* %s_addr.1 ; <sbyte> [#uses=1]
switch sbyte %tmp.1, label %no_exit [
- sbyte 0, label %loopexit
sbyte 46, label %loopexit
+ sbyte 0, label %loopexit
]
We need to stomp all of this stuff out.
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