llvm-6502/test/Transforms/LoopVectorize/reverse_induction.ll
Hao Liu e7769db118 [LoopVectorize] Induction variables: support arbitrary constant step.
Previously, only -1 and +1 step values are supported for induction variables. This patch extends LV to support
arbitrary constant steps.
Initial patch by Alexey Volkov. Some bug fixes are added in the following version.

Differential Revision: http://reviews.llvm.org/D6051 and http://reviews.llvm.org/D7193


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227557 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-30 05:02:21 +00:00

149 lines
4.9 KiB
LLVM

; RUN: opt < %s -loop-vectorize -force-vector-interleave=2 -force-vector-width=4 -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"
; Make sure consecutive vector generates correct negative indices.
; PR15882
; CHECK-LABEL: @reverse_induction_i64(
; CHECK: add <4 x i64> %[[SPLAT:.*]], <i64 0, i64 -1, i64 -2, i64 -3>
; CHECK: add <4 x i64> %[[SPLAT]], <i64 -4, i64 -5, i64 -6, i64 -7>
define i32 @reverse_induction_i64(i64 %startval, i32 * %ptr) {
entry:
br label %for.body
for.body:
%add.i7 = phi i64 [ %startval, %entry ], [ %add.i, %for.body ]
%i.06 = phi i32 [ 0, %entry ], [ %inc4, %for.body ]
%redux5 = phi i32 [ 0, %entry ], [ %inc.redux, %for.body ]
%add.i = add i64 %add.i7, -1
%kind_.i = getelementptr inbounds i32* %ptr, i64 %add.i
%tmp.i1 = load i32* %kind_.i, align 4
%inc.redux = add i32 %tmp.i1, %redux5
%inc4 = add i32 %i.06, 1
%exitcond = icmp ne i32 %inc4, 1024
br i1 %exitcond, label %for.body, label %loopend
loopend:
ret i32 %inc.redux
}
; CHECK-LABEL: @reverse_induction_i128(
; CHECK: add <4 x i128> %[[SPLAT:.*]], <i128 0, i128 -1, i128 -2, i128 -3>
; CHECK: add <4 x i128> %[[SPLAT]], <i128 -4, i128 -5, i128 -6, i128 -7>
define i32 @reverse_induction_i128(i128 %startval, i32 * %ptr) {
entry:
br label %for.body
for.body:
%add.i7 = phi i128 [ %startval, %entry ], [ %add.i, %for.body ]
%i.06 = phi i32 [ 0, %entry ], [ %inc4, %for.body ]
%redux5 = phi i32 [ 0, %entry ], [ %inc.redux, %for.body ]
%add.i = add i128 %add.i7, -1
%kind_.i = getelementptr inbounds i32* %ptr, i128 %add.i
%tmp.i1 = load i32* %kind_.i, align 4
%inc.redux = add i32 %tmp.i1, %redux5
%inc4 = add i32 %i.06, 1
%exitcond = icmp ne i32 %inc4, 1024
br i1 %exitcond, label %for.body, label %loopend
loopend:
ret i32 %inc.redux
}
; CHECK-LABEL: @reverse_induction_i16(
; CHECK: add <4 x i16> %[[SPLAT:.*]], <i16 0, i16 -1, i16 -2, i16 -3>
; CHECK: add <4 x i16> %[[SPLAT]], <i16 -4, i16 -5, i16 -6, i16 -7>
define i32 @reverse_induction_i16(i16 %startval, i32 * %ptr) {
entry:
br label %for.body
for.body:
%add.i7 = phi i16 [ %startval, %entry ], [ %add.i, %for.body ]
%i.06 = phi i32 [ 0, %entry ], [ %inc4, %for.body ]
%redux5 = phi i32 [ 0, %entry ], [ %inc.redux, %for.body ]
%add.i = add i16 %add.i7, -1
%kind_.i = getelementptr inbounds i32* %ptr, i16 %add.i
%tmp.i1 = load i32* %kind_.i, align 4
%inc.redux = add i32 %tmp.i1, %redux5
%inc4 = add i32 %i.06, 1
%exitcond = icmp ne i32 %inc4, 1024
br i1 %exitcond, label %for.body, label %loopend
loopend:
ret i32 %inc.redux
}
@a = common global [1024 x i32] zeroinitializer, align 16
; We incorrectly transformed this loop into an empty one because we left the
; induction variable in i8 type and truncated the exit value 1024 to 0.
; int a[1024];
;
; void fail() {
; int reverse_induction = 1023;
; unsigned char forward_induction = 0;
; while ((reverse_induction) >= 0) {
; forward_induction++;
; a[reverse_induction] = forward_induction;
; --reverse_induction;
; }
; }
; CHECK-LABEL: @reverse_forward_induction_i64_i8(
; CHECK: vector.body
; CHECK: %index = phi i64 [ 0, %vector.ph ], [ %index.next, %vector.body ]
; CHECK: %normalized.idx = sub i64 %index, 0
; CHECK: %offset.idx = sub i64 1023, %normalized.idx
; CHECK: trunc i64 %index to i8
define void @reverse_forward_induction_i64_i8() {
entry:
br label %while.body
while.body:
%indvars.iv = phi i64 [ 1023, %entry ], [ %indvars.iv.next, %while.body ]
%forward_induction.05 = phi i8 [ 0, %entry ], [ %inc, %while.body ]
%inc = add i8 %forward_induction.05, 1
%conv = zext i8 %inc to i32
%arrayidx = getelementptr inbounds [1024 x i32]* @a, i64 0, i64 %indvars.iv
store i32 %conv, i32* %arrayidx, align 4
%indvars.iv.next = add i64 %indvars.iv, -1
%0 = trunc i64 %indvars.iv to i32
%cmp = icmp sgt i32 %0, 0
br i1 %cmp, label %while.body, label %while.end
while.end:
ret void
}
; CHECK-LABEL: @reverse_forward_induction_i64_i8_signed(
; CHECK: vector.body:
; CHECK: %index = phi i64 [ 129, %vector.ph ], [ %index.next, %vector.body ]
; CHECK: %normalized.idx = sub i64 %index, 129
; CHECK: %offset.idx = sub i64 1023, %normalized.idx
; CHECK: trunc i64 %index to i8
define void @reverse_forward_induction_i64_i8_signed() {
entry:
br label %while.body
while.body:
%indvars.iv = phi i64 [ 1023, %entry ], [ %indvars.iv.next, %while.body ]
%forward_induction.05 = phi i8 [ -127, %entry ], [ %inc, %while.body ]
%inc = add i8 %forward_induction.05, 1
%conv = sext i8 %inc to i32
%arrayidx = getelementptr inbounds [1024 x i32]* @a, i64 0, i64 %indvars.iv
store i32 %conv, i32* %arrayidx, align 4
%indvars.iv.next = add i64 %indvars.iv, -1
%0 = trunc i64 %indvars.iv to i32
%cmp = icmp sgt i32 %0, 0
br i1 %cmp, label %while.body, label %while.end
while.end:
ret void
}