1
0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-26 12:43:36 +01:00
llvm-mirror/test/Transforms/BBVectorize/cycle.ll
Hal Finkel d1fc849359 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.

llvm-svn: 167122
2012-10-31 15:17:07 +00:00

113 lines
4.9 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
; This test checks the non-trivial pairing-induced cycle avoidance. Without this cycle avoidance, the algorithm would otherwise
; want to select the pairs:
; %div77 = fdiv double %sub74, %mul76.v.r1 <-> %div125 = fdiv double %mul121, %mul76.v.r2 (div125 depends on mul117)
; %add84 = fadd double %sub83, 2.000000e+00 <-> %add127 = fadd double %mul126, 1.000000e+00 (add127 depends on div77)
; %mul95 = fmul double %sub45.v.r1, %sub36.v.r1 <-> %mul88 = fmul double %sub36.v.r1, %sub87 (mul88 depends on add84)
; %mul117 = fmul double %sub39.v.r1, %sub116 <-> %mul97 = fmul double %mul96, %sub39.v.r1 (mul97 depends on mul95)
; and so a dependency cycle would be created.
declare double @fabs(double) nounwind readnone
define void @test1(double %a, double %b, double %c, double %add80, double %mul1, double %mul2.v.r1, double %mul73, double %sub, double %sub65, double %F.0, i32 %n.0, double %Bnm3.0, double %Bnm2.0, double %Bnm1.0, double %Anm3.0, double %Anm2.0, double %Anm1.0) {
entry:
br label %go
go:
%conv = sitofp i32 %n.0 to double
%add35 = fadd double %conv, %a
%sub36 = fadd double %add35, -1.000000e+00
%add38 = fadd double %conv, %b
%sub39 = fadd double %add38, -1.000000e+00
%add41 = fadd double %conv, %c
%sub42 = fadd double %add41, -1.000000e+00
%sub45 = fadd double %add35, -2.000000e+00
%sub48 = fadd double %add38, -2.000000e+00
%sub51 = fadd double %add41, -2.000000e+00
%mul52 = shl nsw i32 %n.0, 1
%sub53 = add nsw i32 %mul52, -1
%conv54 = sitofp i32 %sub53 to double
%sub56 = add nsw i32 %mul52, -3
%conv57 = sitofp i32 %sub56 to double
%sub59 = add nsw i32 %mul52, -5
%conv60 = sitofp i32 %sub59 to double
%mul61 = mul nsw i32 %n.0, %n.0
%conv62 = sitofp i32 %mul61 to double
%mul63 = fmul double %conv62, 3.000000e+00
%mul67 = fmul double %sub65, %conv
%add68 = fadd double %mul63, %mul67
%add69 = fadd double %add68, 2.000000e+00
%sub71 = fsub double %add69, %mul2.v.r1
%sub74 = fsub double %sub71, %mul73
%mul75 = fmul double %conv57, 2.000000e+00
%mul76 = fmul double %mul75, %sub42
%div77 = fdiv double %sub74, %mul76
%mul82 = fmul double %add80, %conv
%sub83 = fsub double %mul63, %mul82
%add84 = fadd double %sub83, 2.000000e+00
%sub86 = fsub double %add84, %mul2.v.r1
%sub87 = fsub double -0.000000e+00, %sub86
%mul88 = fmul double %sub36, %sub87
%mul89 = fmul double %mul88, %sub39
%mul90 = fmul double %conv54, 4.000000e+00
%mul91 = fmul double %mul90, %conv57
%mul92 = fmul double %mul91, %sub51
%mul93 = fmul double %mul92, %sub42
%div94 = fdiv double %mul89, %mul93
%mul95 = fmul double %sub45, %sub36
%mul96 = fmul double %mul95, %sub48
%mul97 = fmul double %mul96, %sub39
%sub99 = fsub double %conv, %a
%sub100 = fadd double %sub99, -2.000000e+00
%mul101 = fmul double %mul97, %sub100
%sub103 = fsub double %conv, %b
%sub104 = fadd double %sub103, -2.000000e+00
%mul105 = fmul double %mul101, %sub104
%mul106 = fmul double %conv57, 8.000000e+00
%mul107 = fmul double %mul106, %conv57
%mul108 = fmul double %mul107, %conv60
%sub111 = fadd double %add41, -3.000000e+00
%mul112 = fmul double %mul108, %sub111
%mul113 = fmul double %mul112, %sub51
%mul114 = fmul double %mul113, %sub42
%div115 = fdiv double %mul105, %mul114
%sub116 = fsub double -0.000000e+00, %sub36
%mul117 = fmul double %sub39, %sub116
%sub119 = fsub double %conv, %c
%sub120 = fadd double %sub119, -1.000000e+00
%mul121 = fmul double %mul117, %sub120
%mul123 = fmul double %mul75, %sub51
%mul124 = fmul double %mul123, %sub42
%div125 = fdiv double %mul121, %mul124
%mul126 = fmul double %div77, %sub
%add127 = fadd double %mul126, 1.000000e+00
%mul128 = fmul double %add127, %Anm1.0
%mul129 = fmul double %div94, %sub
%add130 = fadd double %div125, %mul129
%mul131 = fmul double %add130, %sub
%mul132 = fmul double %mul131, %Anm2.0
%add133 = fadd double %mul128, %mul132
%mul134 = fmul double %div115, %mul1
%mul135 = fmul double %mul134, %Anm3.0
%add136 = fadd double %add133, %mul135
%mul139 = fmul double %add127, %Bnm1.0
%mul143 = fmul double %mul131, %Bnm2.0
%add144 = fadd double %mul139, %mul143
%mul146 = fmul double %mul134, %Bnm3.0
%add147 = fadd double %add144, %mul146
%div148 = fdiv double %add136, %add147
%sub149 = fsub double %F.0, %div148
%div150 = fdiv double %sub149, %F.0
%call = tail call double @fabs(double %div150) nounwind readnone
%cmp = fcmp olt double %call, 0x3CB0000000000000
%cmp152 = icmp sgt i32 %n.0, 20000
%or.cond = or i1 %cmp, %cmp152
br i1 %or.cond, label %done, label %go
done:
ret void
; CHECK: @test1
; CHECK: go:
; CHECK: %conv.v.i0.1 = insertelement <2 x i32> undef, i32 %n.0, i32 0
; FIXME: When tree pruning is deterministic, include the entire output.
}