llvm-6502/test/Transforms/LoopVectorize/unroll_novec.ll
Nadav Rotem 4bf6326d08 LoopVectorize: Implement partial loop unrolling when vectorization is not profitable.
This patch enables unrolling of loops when vectorization is legal but not profitable.
We add a new class InnerLoopUnroller, that extends InnerLoopVectorizer and replaces some of the vector-specific logic with scalars.

This patch does not introduce any runtime regressions and improves the following workloads:

SingleSource/Benchmarks/Shootout/matrix -22.64%
SingleSource/Benchmarks/Shootout-C++/matrix -13.06%
External/SPEC/CINT2006/464_h264ref/464_h264ref  -3.99%
SingleSource/Benchmarks/Adobe-C++/simple_types_constant_folding -1.95%



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189281 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-26 22:33:26 +00:00

40 lines
1.3 KiB
LLVM

; RUN: opt < %s -loop-vectorize -force-vector-width=1 -force-vector-unroll=2 -dce -instcombine -S | FileCheck %s
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-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx10.8.0"
@a = common global [2048 x i32] zeroinitializer, align 16
; This is the loop.
; for (i=0; i<n; i++){
; a[i] += i;
; }
;CHECK-LABEL: @inc(
;CHECK: load i32*
;CHECK: load i32*
;CHECK: add nsw i32
;CHECK: add nsw i32
;CHECK: store i32
;CHECK: store i32
;CHECK: ret void
define void @inc(i32 %n) nounwind uwtable noinline ssp {
%1 = icmp sgt i32 %n, 0
br i1 %1, label %.lr.ph, label %._crit_edge
.lr.ph: ; preds = %0, %.lr.ph
%indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ 0, %0 ]
%2 = getelementptr inbounds [2048 x i32]* @a, i64 0, i64 %indvars.iv
%3 = load i32* %2, align 4
%4 = trunc i64 %indvars.iv to i32
%5 = add nsw i32 %3, %4
store i32 %5, i32* %2, align 4
%indvars.iv.next = add i64 %indvars.iv, 1
%lftr.wideiv = trunc i64 %indvars.iv.next to i32
%exitcond = icmp eq i32 %lftr.wideiv, %n
br i1 %exitcond, label %._crit_edge, label %.lr.ph
._crit_edge: ; preds = %.lr.ph, %0
ret void
}