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; RUN: opt -passes=loop-idiom -use-lir-code-size-heurs=true < %s -S | FileCheck %s
; When compiling for codesize we avoid idiom recognition for a
; multi-block loop unless it is one of
; - a loop_memset idiom, or
; - a memset/memcpy idiom in a nested loop.
declare void @llvm.memset.p0.i64(ptr nocapture, i8, i64, i1)
@APPLES = common global i32 0, align 4
@ORANGES = common global i32 0, align 4
; LIR allowed: loop_memset idiom in multi-block loop.
; ===================================================
; CHECK-LABEL: @LoopMemset
; CHECK: for.body.preheader:
; CHECK: call void @llvm.memset
; CHECK: for.body:
;
define i32 @LoopMemset([2048 x i8]* noalias nocapture %DST, i32 %SIZE) local_unnamed_addr optsize {
entry:
%cmp12 = icmp sgt i32 %SIZE, 0
br i1 %cmp12, label %for.body.preheader, label %for.end
for.body.preheader: ; preds = %entry
br label %for.body
for.body: ; preds = %for.body.preheader, %for.inc
%indvars.iv = phi i64 [ 0, %for.body.preheader ], [ %indvars.iv.next, %for.inc ]
%BASKET.013 = phi i32 [ %BASKET.1, %for.inc ], [ 0, %for.body.preheader ]
%arraydecay = getelementptr inbounds [2048 x i8], ptr %DST, i64 %indvars.iv, i64 0
tail call void @llvm.memset.p0.i64(ptr %arraydecay, i8 -1, i64 2048, i1 false)
%0 = trunc i64 %indvars.iv to i32
%rem11 = and i32 %0, 1
%cmp1 = icmp eq i32 %rem11, 0
%1 = load i32, ptr @ORANGES, align 4
%2 = load i32, ptr @APPLES, align 4
br i1 %cmp1, label %if.then, label %if.else
if.else: ; preds = %for.body
%dec3 = add nsw i32 %2, -1
store i32 %dec3, ptr @APPLES, align 4
br label %for.inc
if.then: ; preds = %for.body
%dec = add nsw i32 %1, -1
store i32 %dec, ptr @ORANGES, align 4
br label %for.inc
for.inc: ; preds = %if.then, %if.else
%.pn = phi i32 [ %2, %if.then ], [ %1, %if.else ]
%BASKET.1 = add nsw i32 %.pn, %BASKET.013
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
%lftr.wideiv = trunc i64 %indvars.iv.next to i32
%exitcond = icmp ne i32 %lftr.wideiv, %SIZE
br i1 %exitcond, label %for.body, label %for.end.loopexit
for.end.loopexit: ; preds = %for.inc
%BASKET.1.lcssa = phi i32 [ %BASKET.1, %for.inc ]
br label %for.end
for.end: ; preds = %for.end.loopexit, %entry
%BASKET.0.lcssa = phi i32 [ 0, %entry ], [ %BASKET.1.lcssa, %for.end.loopexit ]
ret i32 %BASKET.0.lcssa
}
; LIR allowed: memset idiom in multi-block nested loop,
; which is recognized as a loop_memset in its turn.
; =====================================================
; CHECK-LABEL: @NestedMemset_LoopMemset
; CHECK: for.cond1.preheader.preheader:
; CHECK: call void @llvm.memset
; CHECK: for.cond1.preheader:
;
define i32 @NestedMemset_LoopMemset([2046 x i8]* noalias nocapture %DST, i32 %SIZE) local_unnamed_addr optsize {
entry:
%cmp25 = icmp sgt i32 %SIZE, 0
br i1 %cmp25, label %for.cond1.preheader.preheader, label %for.end11
for.cond1.preheader.preheader: ; preds = %entry
br label %for.cond1.preheader
for.cond1.preheader: ; preds = %for.cond1.preheader.preheader, %for.inc9
%i.027 = phi i32 [ %inc10, %for.inc9 ], [ 0, %for.cond1.preheader.preheader ]
%BASKET.026 = phi i32 [ %BASKET.2.lcssa, %for.inc9 ], [ 0, %for.cond1.preheader.preheader ]
%idxprom4 = sext i32 %i.027 to i64
%rem22 = and i32 %i.027, 1
%cmp6 = icmp eq i32 %rem22, 0
br label %for.body3
for.body3: ; preds = %for.cond1.preheader, %for.inc
%indvars.iv = phi i64 [ 0, %for.cond1.preheader ], [ %indvars.iv.next, %for.inc ]
%BASKET.123 = phi i32 [ %BASKET.026, %for.cond1.preheader ], [ %BASKET.2, %for.inc ]
%arrayidx5 = getelementptr inbounds [2046 x i8], ptr %DST, i64 %idxprom4, i64 %indvars.iv
store i8 -1, ptr %arrayidx5, align 1
%0 = load i32, ptr @APPLES, align 4
%1 = load i32, ptr @ORANGES, align 4
br i1 %cmp6, label %if.then, label %if.else
if.else: ; preds = %for.body3
%dec8 = add nsw i32 %0, -1
store i32 %dec8, ptr @APPLES, align 4
br label %for.inc
if.then: ; preds = %for.body3
%dec = add nsw i32 %1, -1
store i32 %dec, ptr @ORANGES, align 4
br label %for.inc
for.inc: ; preds = %if.then, %if.else
%.pn = phi i32 [ %0, %if.then ], [ %1, %if.else ]
%BASKET.2 = add nsw i32 %.pn, %BASKET.123
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
%exitcond = icmp ne i64 %indvars.iv.next, 2046
br i1 %exitcond, label %for.body3, label %for.inc9
for.inc9: ; preds = %for.inc
%BASKET.2.lcssa = phi i32 [ %BASKET.2, %for.inc ]
%inc10 = add nsw i32 %i.027, 1
%cmp = icmp slt i32 %inc10, %SIZE
br i1 %cmp, label %for.cond1.preheader, label %for.end11.loopexit
for.end11.loopexit: ; preds = %for.inc9
%BASKET.2.lcssa.lcssa = phi i32 [ %BASKET.2.lcssa, %for.inc9 ]
br label %for.end11
for.end11: ; preds = %for.end11.loopexit, %entry
%BASKET.0.lcssa = phi i32 [ 0, %entry ], [ %BASKET.2.lcssa.lcssa, %for.end11.loopexit ]
ret i32 %BASKET.0.lcssa
}
; LIR avoided: memset idiom in multi-block top-level loop.
; ========================================================
; CHECK-LABEL: @Non_NestedMemset
; CHECK-NOT: call void @llvm.memset
;
define i32 @Non_NestedMemset(i8* noalias nocapture %DST, i32 %SIZE) local_unnamed_addr optsize {
entry:
%cmp12 = icmp sgt i32 %SIZE, 0
br i1 %cmp12, label %for.body.preheader, label %for.end
for.body.preheader: ; preds = %entry
br label %for.body
for.body: ; preds = %for.body.preheader, %for.inc
%indvars.iv = phi i64 [ 0, %for.body.preheader ], [ %indvars.iv.next, %for.inc ]
%BASKET.013 = phi i32 [ %BASKET.1, %for.inc ], [ 0, %for.body.preheader ]
%arrayidx = getelementptr inbounds i8, ptr %DST, i64 %indvars.iv
store i8 -1, ptr %arrayidx, align 1
%0 = trunc i64 %indvars.iv to i32
%rem11 = and i32 %0, 1
%cmp1 = icmp eq i32 %rem11, 0
%1 = load i32, ptr @ORANGES, align 4
%2 = load i32, ptr @APPLES, align 4
br i1 %cmp1, label %if.then, label %if.else
if.else: ; preds = %for.body
%dec3 = add nsw i32 %2, -1
store i32 %dec3, ptr @APPLES, align 4
br label %for.inc
if.then: ; preds = %for.body
%dec = add nsw i32 %1, -1
store i32 %dec, ptr @ORANGES, align 4
br label %for.inc
for.inc: ; preds = %if.then, %if.else
%.pn = phi i32 [ %2, %if.then ], [ %1, %if.else ]
%BASKET.1 = add nsw i32 %.pn, %BASKET.013
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
%lftr.wideiv = trunc i64 %indvars.iv.next to i32
%exitcond = icmp ne i32 %lftr.wideiv, %SIZE
br i1 %exitcond, label %for.body, label %for.end.loopexit
for.end.loopexit: ; preds = %for.inc
%BASKET.1.lcssa = phi i32 [ %BASKET.1, %for.inc ]
br label %for.end
for.end: ; preds = %for.end.loopexit, %entry
%BASKET.0.lcssa = phi i32 [ 0, %entry ], [ %BASKET.1.lcssa, %for.end.loopexit ]
ret i32 %BASKET.0.lcssa
}
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