llvm-6502/test/Transforms/LoopReroll/nonconst_lb.ll
Jingyue Wu 5d59315f13 [LSR] canonicalize Prod*(1<<C) to Prod<<C
Summary:
Because LSR happens at a late stage where mul of a power of 2 is
typically canonicalized to shl, this canonicalization emits code that
can be better CSE'ed.

Test Plan:
Transforms/LoopStrengthReduce/shl.ll shows how this change makes GVN more
powerful. Fixes some existing tests due to this change.

Reviewers: sanjoy, majnemer, atrick

Reviewed By: majnemer, atrick

Subscribers: majnemer, llvm-commits

Differential Revision: http://reviews.llvm.org/D10448

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240573 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-24 19:28:40 +00:00

153 lines
6.0 KiB
LLVM

; RUN: opt < %s -loop-reroll -S | FileCheck %s
target datalayout = "e-p:32:32:32-i1:8:32-i8:8:32-i16:16:32-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:32:64-v128:32:128-a0:0:32-n32-S32"
target triple = "thumbv7-none-linux"
;void foo(int *A, int *B, int m, int n) {
; for (int i = m; i < n; i+=4) {
; A[i+0] = B[i+0] * 4;
; A[i+1] = B[i+1] * 4;
; A[i+2] = B[i+2] * 4;
; A[i+3] = B[i+3] * 4;
; }
;}
define void @foo(i32* nocapture %A, i32* nocapture readonly %B, i32 %m, i32 %n) {
entry:
%cmp34 = icmp slt i32 %m, %n
br i1 %cmp34, label %for.body, label %for.end
for.body: ; preds = %entry, %for.body
%i.035 = phi i32 [ %add18, %for.body ], [ %m, %entry ]
%arrayidx = getelementptr inbounds i32, i32* %B, i32 %i.035
%0 = load i32, i32* %arrayidx, align 4
%mul = shl nsw i32 %0, 2
%arrayidx2 = getelementptr inbounds i32, i32* %A, i32 %i.035
store i32 %mul, i32* %arrayidx2, align 4
%add3 = add nsw i32 %i.035, 1
%arrayidx4 = getelementptr inbounds i32, i32* %B, i32 %add3
%1 = load i32, i32* %arrayidx4, align 4
%mul5 = shl nsw i32 %1, 2
%arrayidx7 = getelementptr inbounds i32, i32* %A, i32 %add3
store i32 %mul5, i32* %arrayidx7, align 4
%add8 = add nsw i32 %i.035, 2
%arrayidx9 = getelementptr inbounds i32, i32* %B, i32 %add8
%2 = load i32, i32* %arrayidx9, align 4
%mul10 = shl nsw i32 %2, 2
%arrayidx12 = getelementptr inbounds i32, i32* %A, i32 %add8
store i32 %mul10, i32* %arrayidx12, align 4
%add13 = add nsw i32 %i.035, 3
%arrayidx14 = getelementptr inbounds i32, i32* %B, i32 %add13
%3 = load i32, i32* %arrayidx14, align 4
%mul15 = shl nsw i32 %3, 2
%arrayidx17 = getelementptr inbounds i32, i32* %A, i32 %add13
store i32 %mul15, i32* %arrayidx17, align 4
%add18 = add nsw i32 %i.035, 4
%cmp = icmp slt i32 %add18, %n
br i1 %cmp, label %for.body, label %for.end
for.end: ; preds = %for.body, %entry
ret void
}
; CHECK-LABEL: @foo
; CHECK: for.body.preheader: ; preds = %entry
; CHECK: %0 = add i32 %n, -1
; CHECK: %1 = sub i32 %0, %m
; CHECK: %2 = lshr i32 %1, 2
; CHECK: %3 = shl i32 %2, 2
; CHECK: %4 = add i32 %m, %3
; CHECK: %5 = add i32 %4, 3
; CHECK: br label %for.body
; CHECK: for.body: ; preds = %for.body, %for.body.preheader
; CHECK: %indvar = phi i32 [ %indvar.next, %for.body ], [ 0, %for.body.preheader ]
; CHECK: %6 = add i32 %m, %indvar
; CHECK: %arrayidx = getelementptr inbounds i32, i32* %B, i32 %6
; CHECK: %7 = load i32, i32* %arrayidx, align 4
; CHECK: %mul = shl nsw i32 %7, 2
; CHECK: %arrayidx2 = getelementptr inbounds i32, i32* %A, i32 %6
; CHECK: store i32 %mul, i32* %arrayidx2, align 4
; CHECK: %indvar.next = add i32 %indvar, 1
; CHECK: %exitcond = icmp eq i32 %6, %5
; CHECK: br i1 %exitcond, label %for.end, label %for.body
;void daxpy_ur(int n,float da,float *dx,float *dy)
; {
; int m = n % 4;
; for (int i = m; i < n; i = i + 4)
; {
; dy[i] = dy[i] + da*dx[i];
; dy[i+1] = dy[i+1] + da*dx[i+1];
; dy[i+2] = dy[i+2] + da*dx[i+2];
; dy[i+3] = dy[i+3] + da*dx[i+3];
; }
; }
define void @daxpy_ur(i32 %n, float %da, float* nocapture readonly %dx, float* nocapture %dy) {
entry:
%rem = srem i32 %n, 4
%cmp55 = icmp slt i32 %rem, %n
br i1 %cmp55, label %for.body, label %for.end
for.body: ; preds = %entry, %for.body
%i.056 = phi i32 [ %add27, %for.body ], [ %rem, %entry ]
%arrayidx = getelementptr inbounds float, float* %dy, i32 %i.056
%0 = load float, float* %arrayidx, align 4
%arrayidx1 = getelementptr inbounds float, float* %dx, i32 %i.056
%1 = load float, float* %arrayidx1, align 4
%mul = fmul float %1, %da
%add = fadd float %0, %mul
store float %add, float* %arrayidx, align 4
%add3 = add nsw i32 %i.056, 1
%arrayidx4 = getelementptr inbounds float, float* %dy, i32 %add3
%2 = load float, float* %arrayidx4, align 4
%arrayidx6 = getelementptr inbounds float, float* %dx, i32 %add3
%3 = load float, float* %arrayidx6, align 4
%mul7 = fmul float %3, %da
%add8 = fadd float %2, %mul7
store float %add8, float* %arrayidx4, align 4
%add11 = add nsw i32 %i.056, 2
%arrayidx12 = getelementptr inbounds float, float* %dy, i32 %add11
%4 = load float, float* %arrayidx12, align 4
%arrayidx14 = getelementptr inbounds float, float* %dx, i32 %add11
%5 = load float, float* %arrayidx14, align 4
%mul15 = fmul float %5, %da
%add16 = fadd float %4, %mul15
store float %add16, float* %arrayidx12, align 4
%add19 = add nsw i32 %i.056, 3
%arrayidx20 = getelementptr inbounds float, float* %dy, i32 %add19
%6 = load float, float* %arrayidx20, align 4
%arrayidx22 = getelementptr inbounds float, float* %dx, i32 %add19
%7 = load float, float* %arrayidx22, align 4
%mul23 = fmul float %7, %da
%add24 = fadd float %6, %mul23
store float %add24, float* %arrayidx20, align 4
%add27 = add nsw i32 %i.056, 4
%cmp = icmp slt i32 %add27, %n
br i1 %cmp, label %for.body, label %for.end
for.end: ; preds = %for.body, %entry
ret void
}
; CHECK-LABEL: @daxpy_ur
; CHECK: for.body.preheader:
; CHECK: %0 = add i32 %n, -1
; CHECK: %1 = sub i32 %0, %rem
; CHECK: %2 = lshr i32 %1, 2
; CHECK: %3 = shl i32 %2, 2
; CHECK: %4 = add i32 %rem, %3
; CHECK: %5 = add i32 %4, 3
; CHECK: br label %for.body
; CHECK: for.body:
; CHECK: %indvar = phi i32 [ %indvar.next, %for.body ], [ 0, %for.body.preheader ]
; CHECK: %6 = add i32 %rem, %indvar
; CHECK: %arrayidx = getelementptr inbounds float, float* %dy, i32 %6
; CHECK: %7 = load float, float* %arrayidx, align 4
; CHECK: %arrayidx1 = getelementptr inbounds float, float* %dx, i32 %6
; CHECK: %8 = load float, float* %arrayidx1, align 4
; CHECK: %mul = fmul float %8, %da
; CHECK: %add = fadd float %7, %mul
; CHECK: store float %add, float* %arrayidx, align 4
; CHECK: %indvar.next = add i32 %indvar, 1
; CHECK: %exitcond = icmp eq i32 %6, %5
; CHECK: br i1 %exitcond, label %for.end, label %for.body