4 Commits

Author SHA1 Message Date
Craig Topper b5c5010513 [X86] When lowering unsigned v2i64 setcc without SSE42, flip the sign bits in the v2i64 type then bitcast to v4i32.
This may give slightly better opportunities for DAG combine to simplify with the operations before the setcc. It also matches the type the xors will eventually be promoted to anyway so it saves a legalization step.

Almost all of the test changes are because our constant pool entry is now v2i64 instead of v4i32 on 64-bit targets. On 32-bit targets getConstant should be emitting a v4i32 build_vector and a v4i32->v2i64 bitcast.

There are a couple test cases where it appears we now combine a bitwise not with one of these xors which caused a new constant vector to be generated. This prevented a constant pool entry from being shared. But if that's an issue we're concerned about, it seems we need to address it another way that just relying a bitcast to hide it.

This came about from experiments I've been trying with pushing the promotion of and/or/xor to vXi64 later than LegalizeVectorOps where it is today. We run LegalizeVectorOps in a bottom up order. So the and/or/xor are promoted before their users are legalized. The bitcasts added for the promotion act as a barrier to computeKnownBits if we try to use it during vector legalization of a later operation. So by moving the promotion out we can hopefully get better results from computeKnownBits/computeNumSignBits like in LowerTruncate on AVX512. I've also looked at running LegalizeVectorOps in a top down order like LegalizeDAG, but thats showing some other issues.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344071 91177308-0d34-0410-b5e6-96231b3b80d8
2018-10-09 19:05:50 +00:00
Francis Visoiu Mistrih ca0df55065 [CodeGen] Unify MBB reference format in both MIR and debug output
As part of the unification of the debug format and the MIR format, print
MBB references as '%bb.5'.

The MIR printer prints the IR name of a MBB only for block definitions.

* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)->getNumber\(\)/" << printMBBReference(*\1)/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)\.getNumber\(\)/" << printMBBReference(\1)/g'
* find . \( -name "*.txt" -o -name "*.s" -o -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#([0-9]+)/%bb.\1/g'
* grep -nr 'BB#' and fix

Differential Revision: https://reviews.llvm.org/D40422

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@319665 91177308-0d34-0410-b5e6-96231b3b80d8
2017-12-04 17:18:51 +00:00
Sanjay Patel 705f5b195b [x86] avoid flipping sign bits for vector icmp by using known bits
If we know that both operands of an unsigned integer vector comparison are non-negative, 
then it's safe to directly use a signed-compare-greater-than instruction (the only non-equality
integer vector compare predicate provided by SSE/AVX).

We're intentionally not changing the condition code to signed in order to preserve the
existing transforms that use min/max/psubus below here.

This should solve PR33276:
https://bugs.llvm.org/show_bug.cgi?id=33276

Differential Revision: https://reviews.llvm.org/D33862


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304909 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-07 13:46:34 +00:00
Sanjay Patel b2d54d6280 [x86] add tests for unsigned vector compares with known signbits; NFC (PR33276)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304612 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-02 23:24:28 +00:00