llvm/test/Transforms/BBVectorize/simple-sel.ll
Hal Finkel 72465ea23d BBVectorize: Choose pair ordering to minimize shuffles
BBVectorize would, except for loads and stores, always fuse instructions
so that the first instruction (in the current source order) would always
represent the low part of the input vectors and the second instruction
would always represent the high part. This lead to too many shuffles
being produced because sometimes the opposite order produces fewer of them.

With this change, BBVectorize tracks the kind of pair connections that form
the DAG of candidate pairs, and uses that information to reorder the pairs to
avoid excess shuffles. Using this information, a future commit will be able
to add VTTI-based shuffle costs to the pair selection procedure. Importantly,
the number of remaining shuffles can now be estimated during pair selection.

There are some trivial instruction reorderings in the test cases, and one
simple additional test where we certainly want to do a reordering to
avoid an unnecessary shuffle.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167122 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-31 15:17:07 +00:00

60 lines
2.8 KiB
LLVM

target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128"
; RUN: opt < %s -bb-vectorize -bb-vectorize-req-chain-depth=3 -instcombine -gvn -S | FileCheck %s
; RUN: opt < %s -bb-vectorize -bb-vectorize-req-chain-depth=3 -bb-vectorize-no-bools -instcombine -gvn -S | FileCheck %s -check-prefix=CHECK-NB
; Basic depth-3 chain with select
define double @test1(double %A1, double %A2, double %B1, double %B2, i1 %C1, i1 %C2) {
; CHECK: @test1
; CHECK: %X1.v.i1.1 = insertelement <2 x double> undef, double %B1, i32 0
; CHECK: %X1.v.i1.2 = insertelement <2 x double> %X1.v.i1.1, double %B2, i32 1
; CHECK: %X1.v.i0.1 = insertelement <2 x double> undef, double %A1, i32 0
; CHECK: %X1.v.i0.2 = insertelement <2 x double> %X1.v.i0.1, double %A2, i32 1
%X1 = fsub double %A1, %B1
%X2 = fsub double %A2, %B2
; CHECK: %X1 = fsub <2 x double> %X1.v.i0.2, %X1.v.i1.2
%Y1 = fmul double %X1, %A1
%Y2 = fmul double %X2, %A2
; CHECK: %Y1 = fmul <2 x double> %X1, %X1.v.i0.2
%Z1 = select i1 %C1, double %Y1, double %B1
%Z2 = select i1 %C2, double %Y2, double %B2
; CHECK: %Z1.v.i0.1 = insertelement <2 x i1> undef, i1 %C1, i32 0
; CHECK: %Z1.v.i0.2 = insertelement <2 x i1> %Z1.v.i0.1, i1 %C2, i32 1
; CHECK: %Z1 = select <2 x i1> %Z1.v.i0.2, <2 x double> %Y1, <2 x double> %X1.v.i1.2
%R = fmul double %Z1, %Z2
; CHECK: %Z1.v.r1 = extractelement <2 x double> %Z1, i32 0
; CHECK: %Z1.v.r2 = extractelement <2 x double> %Z1, i32 1
; CHECK: %R = fmul double %Z1.v.r1, %Z1.v.r2
ret double %R
; CHECK: ret double %R
}
; Basic depth-3 chain with select (and vect. compare)
define double @test2(double %A1, double %A2, double %B1, double %B2) {
; CHECK: @test2
; CHECK-NB: @test2
; CHECK: %X1.v.i1.1 = insertelement <2 x double> undef, double %B1, i32 0
; CHECK: %X1.v.i1.2 = insertelement <2 x double> %X1.v.i1.1, double %B2, i32 1
; CHECK: %X1.v.i0.1 = insertelement <2 x double> undef, double %A1, i32 0
; CHECK: %X1.v.i0.2 = insertelement <2 x double> %X1.v.i0.1, double %A2, i32 1
%X1 = fsub double %A1, %B1
%X2 = fsub double %A2, %B2
; CHECK: %X1 = fsub <2 x double> %X1.v.i0.2, %X1.v.i1.2
%Y1 = fmul double %X1, %A1
%Y2 = fmul double %X2, %A2
; CHECK: %Y1 = fmul <2 x double> %X1, %X1.v.i0.2
%C1 = fcmp ogt double %X1, %A1
%C2 = fcmp ogt double %X2, %A2
; CHECK: %C1 = fcmp ogt <2 x double> %X1, %X1.v.i0.2
; CHECK-NB: fcmp ogt double
%Z1 = select i1 %C1, double %Y1, double %B1
%Z2 = select i1 %C2, double %Y2, double %B2
; CHECK: %Z1 = select <2 x i1> %C1, <2 x double> %Y1, <2 x double> %X1.v.i1.2
%R = fmul double %Z1, %Z2
; CHECK: %Z1.v.r1 = extractelement <2 x double> %Z1, i32 0
; CHECK: %Z1.v.r2 = extractelement <2 x double> %Z1, i32 1
; CHECK: %R = fmul double %Z1.v.r1, %Z1.v.r2
ret double %R
; CHECK: ret double %R
}