llvm-6502/test/Transforms/LoopVectorize/X86/unroll_selection.ll
Nadav Rotem 0bbbc52dc8 LoopVectorizer: Implement a new heuristics for selecting the unroll factor.
We ignore the cpu frontend and focus on pipeline utilization. We do this because we
don't have a good way to estimate the loop body size at the IR level.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172964 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-20 05:24:29 +00:00

72 lines
2.4 KiB
LLVM

; RUN: opt < %s -loop-vectorize -mtriple=x86_64-apple-macosx10.8.0 -mcpu=corei7-avx -force-vector-width=4 -force-vector-unroll=0 -dce -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"
; Don't unroll when we have register pressure.
;CHECK: reg_pressure
;CHECK: load <4 x double>
;CHECK-NOT: load <4 x double>
;CHECK: store <4 x double>
;CHECK-NOT: store <4 x double>
;CHECK: ret
define void @reg_pressure(double* nocapture %A, i32 %n) nounwind uwtable ssp {
%1 = sext i32 %n to i64
br label %2
; <label>:2 ; preds = %2, %0
%indvars.iv = phi i64 [ %indvars.iv.next, %2 ], [ %1, %0 ]
%3 = getelementptr inbounds double* %A, i64 %indvars.iv
%4 = load double* %3, align 8
%5 = fadd double %4, 3.000000e+00
%6 = fmul double %4, 2.000000e+00
%7 = fadd double %5, %6
%8 = fadd double %7, 2.000000e+00
%9 = fmul double %8, 5.000000e-01
%10 = fadd double %6, %9
%11 = fsub double %10, %5
%12 = fadd double %4, %11
%13 = fdiv double %8, %12
%14 = fmul double %13, %8
%15 = fmul double %6, %14
%16 = fmul double %5, %15
%17 = fadd double %16, -3.000000e+00
%18 = fsub double %4, %5
%19 = fadd double %6, %18
%20 = fadd double %13, %19
%21 = fadd double %20, %17
%22 = fadd double %21, 3.000000e+00
%23 = fmul double %4, %22
store double %23, double* %3, align 8
%indvars.iv.next = add i64 %indvars.iv, -1
%24 = trunc i64 %indvars.iv to i32
%25 = icmp eq i32 %24, 0
br i1 %25, label %26, label %2
; <label>:26 ; preds = %2
ret void
}
; This is a small loop. Unroll it twice.
;CHECK: small_loop
;CHECK: xor
;CHECK: xor
;CHECK: ret
define void @small_loop(i16* nocapture %A, i64 %n) nounwind uwtable ssp {
%1 = icmp eq i64 %n, 0
br i1 %1, label %._crit_edge, label %.lr.ph
.lr.ph: ; preds = %0, %.lr.ph
%i.01 = phi i64 [ %5, %.lr.ph ], [ 0, %0 ]
%2 = getelementptr inbounds i16* %A, i64 %i.01
%3 = load i16* %2, align 2
%4 = xor i16 %3, 3
store i16 %4, i16* %2, align 2
%5 = add i64 %i.01, 1
%exitcond = icmp eq i64 %5, %n
br i1 %exitcond, label %._crit_edge, label %.lr.ph
._crit_edge: ; preds = %.lr.ph, %0
ret void
}