caused SPASS to fail building last night.
We can't trivially unswitch a loop if the exit block has phi nodes in it,
because we don't know which predecessor to use.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26320 91177308-0d34-0410-b5e6-96231b3b80d8
and ComputeMaskedBits to match the new improved versions in instcombine.
Tested against all of multisource/benchmarks on ppc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26238 91177308-0d34-0410-b5e6-96231b3b80d8
This fixes a testcase that nate reduced from spass.
Also included are a couple minor code changes that don't affect the generated
code at all.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26235 91177308-0d34-0410-b5e6-96231b3b80d8
unswitch this loop on 2 before sweating to unswitch on 1/3.
void test4(int N, int i, int C, int*P, int*Q) {
int j;
for (j = 0; j < N; ++j) {
switch (C) { // general unswitching.
default: P[i+j] = 0; break;
case 1: Q[i+j] = 0; break;
case 3: P[i+j] = Q[i+j]; break;
case 2: break; // TRIVIAL UNSWITCH on C==2
}
}
}
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26223 91177308-0d34-0410-b5e6-96231b3b80d8
this for example:
for (j = 0; j < N; ++j) { // trivial unswitch
if (C)
P[i+j] = 0;
}
turning it into the obvious code without bothering to duplicate an empty loop.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26220 91177308-0d34-0410-b5e6-96231b3b80d8
1. Teach GetConstantInType to handle boolean constants.
2. Teach instcombine to fold (compare X, CST) when X has known 0/1 bits.
Testcase here: set.ll:test22
3. Improve the "(X >> c1) & C2 == 0" folding code to allow a noop cast
between the shift and and. More aggressive bitfolding for other reasons
was turning signed shr's into unsigned shr's, leaving the noop cast in
the way.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26131 91177308-0d34-0410-b5e6-96231b3b80d8
This allows us to simplify on conditions where bits are not known, but they
are not demanded either! This also fixes a couple of bugs in
ComputeMaskedBits that were exposed during this work.
In the future, swaths of instcombine should be removed, as this code
subsumes a bunch of ad-hockery.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26122 91177308-0d34-0410-b5e6-96231b3b80d8
uses of loop values outside the loop. We need loop-closed SSA form to do
this right, or to use SSA rewriting if we really care.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26089 91177308-0d34-0410-b5e6-96231b3b80d8
1. Teach it new tricks: in particular how to propagate through signed shr and sexts.
2. Teach it to return a bitset of known-1 and known-0 bits, instead of just zero.
3. Teach instcombine (AND X, C) to fold when we know all C bits of X.
This implements Regression/Transforms/InstCombine/bittest.ll, and allows
future things to be simplified.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26087 91177308-0d34-0410-b5e6-96231b3b80d8
instruction onto the worklist (in case they are now dead).
Add a really trivial local DSE implementation to help out bitfield code.
We now fold this:
struct S {
unsigned char a : 1, b : 1, c : 1, d : 2, e : 3;
S();
};
S::S() : a(0), b(0), c(1), d(0), e(6) {}
to this:
void %_ZN1SC1Ev(%struct.S* %this) {
entry:
%tmp.1 = getelementptr %struct.S* %this, int 0, uint 0
store ubyte 38, ubyte* %tmp.1
ret void
}
much earlier (in gccas instead of only in gccld after DSE runs).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26050 91177308-0d34-0410-b5e6-96231b3b80d8
is just as efficient as MVIZ and is also more general.
Fix a few minor bugs introduced in recent patches
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26036 91177308-0d34-0410-b5e6-96231b3b80d8
mask. This allows the code to be simpler and more efficient.
Also, generalize some of the cases in MVIZ a bit, making it slightly more aggressive.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26035 91177308-0d34-0410-b5e6-96231b3b80d8
'demanded bits', inspired by Nate's work in the dag combiner. This isn't
complete, but needs to unrelated instcombiner changes to continue.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26033 91177308-0d34-0410-b5e6-96231b3b80d8
Turn A / (C1 << N), where C1 is "1<<C2" into A >> (N+C2) [udiv only].
Tested with: rem.ll:test5, div.ll:test10
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26003 91177308-0d34-0410-b5e6-96231b3b80d8
1. When rewriting code in outer loops, sometimes we would insert code into
inner loops that is invariant in that loop.
2. Notice that 4*(2+x) is 8+4*x and use that to simplify expressions.
This is a performance neutral change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25964 91177308-0d34-0410-b5e6-96231b3b80d8
1. Do not statically construct a map when the program starts up, this
is expensive and cannot be optimized. Instead, create a list.
2. Do not insert entries for all function in the module into a hashmap
that lives the full life of the compiler.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25512 91177308-0d34-0410-b5e6-96231b3b80d8
1. Use the varargs version of getOrInsertFunction to simplify code.
2. remove #include
3. Reduce the number of #ifdef's.
4. remove extraneous vertical whitespace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25508 91177308-0d34-0410-b5e6-96231b3b80d8
Don't do floor->floorf conversion if floorf is not available. This checks
the compiler's host, not its target, which is incorrect for cross-compilers
Not sure that's important as we don't build many cross-compilers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25456 91177308-0d34-0410-b5e6-96231b3b80d8
This patch is an incremental step towards supporting a flat symbol table.
It de-overloads the intrinsic functions by providing type-specific intrinsics
and arranging for automatically upgrading from the old overloaded name to
the new non-overloaded name. Specifically:
llvm.isunordered -> llvm.isunordered.f32, llvm.isunordered.f64
llvm.sqrt -> llvm.sqrt.f32, llvm.sqrt.f64
llvm.ctpop -> llvm.ctpop.i8, llvm.ctpop.i16, llvm.ctpop.i32, llvm.ctpop.i64
llvm.ctlz -> llvm.ctlz.i8, llvm.ctlz.i16, llvm.ctlz.i32, llvm.ctlz.i64
llvm.cttz -> llvm.cttz.i8, llvm.cttz.i16, llvm.cttz.i32, llvm.cttz.i64
New code should not use the overloaded intrinsic names. Warnings will be
emitted if they are used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25366 91177308-0d34-0410-b5e6-96231b3b80d8
it doesn't contain any calls. This is a fairly common case for C++ code,
so it will probably speed up the inliner marginally in these cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25284 91177308-0d34-0410-b5e6-96231b3b80d8
function was not an alloca, we wouldn't check the entry block for any allocas,
leading to increased stack space in some cases. In practice, allocas are almost
always at the top of the block, so this was never noticed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25280 91177308-0d34-0410-b5e6-96231b3b80d8