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; Test shrink wrapping placement is correct with respect to calls to llvm.{stacksave,stackrestore}
; void f(int n, int x[]) {
; if (n < 0)
; return;
;
; int a[n];
;
; for (int i = 0; i < n; i++)
; a[i] = x[n - i - 1];
;
; for (int i = 0; i < n; i++)
; x[i] = a[i] + 1;
; }
;
; RUN: llc -mtriple aarch64-linux %s -o - | FileCheck %s
define dso_local void @f(i32 %n, i32* nocapture %x) {
entry:
%cmp = icmp slt i32 %n, 0
br i1 %cmp, label %return, label %if.end
if.end: ; preds = %entry
%0 = zext i32 %n to i64
%1 = tail call i8* @llvm.stacksave()
%vla = alloca i32, i64 %0, align 16
%cmp132 = icmp eq i32 %n, 0
br i1 %cmp132, label %for.cond.cleanup8, label %for.body.lr.ph
for.body.lr.ph: ; preds = %if.end
%sub = add i32 %n, -1
br label %for.body
for.cond6.preheader: ; preds = %for.body
%cmp730 = icmp sgt i32 %n, 0
br i1 %cmp730, label %for.body9, label %for.cond.cleanup8
for.body: ; preds = %for.body, %for.body.lr.ph
%indvars.iv34 = phi i64 [ 0, %for.body.lr.ph ], [ %indvars.iv.next35, %for.body ]
%2 = trunc i64 %indvars.iv34 to i32
%sub2 = sub i32 %sub, %2
%idxprom = sext i32 %sub2 to i64
%arrayidx = getelementptr inbounds i32, i32* %x, i64 %idxprom
%3 = load i32, i32* %arrayidx, align 4
%arrayidx4 = getelementptr inbounds i32, i32* %vla, i64 %indvars.iv34
store i32 %3, i32* %arrayidx4, align 4
%indvars.iv.next35 = add nuw nsw i64 %indvars.iv34, 1
%exitcond37 = icmp eq i64 %indvars.iv.next35, %0
br i1 %exitcond37, label %for.cond6.preheader, label %for.body
for.cond.cleanup8: ; preds = %for.body9, %if.end, %for.cond6.preheader
tail call void @llvm.stackrestore(i8* %1)
br label %return
for.body9: ; preds = %for.cond6.preheader, %for.body9
%indvars.iv = phi i64 [ %indvars.iv.next, %for.body9 ], [ 0, %for.cond6.preheader ]
%arrayidx11 = getelementptr inbounds i32, i32* %vla, i64 %indvars.iv
%4 = load i32, i32* %arrayidx11, align 4
%add = add nsw i32 %4, 1
%arrayidx13 = getelementptr inbounds i32, i32* %x, i64 %indvars.iv
store i32 %add, i32* %arrayidx13, align 4
%indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
%exitcond = icmp eq i64 %indvars.iv.next, %0
br i1 %exitcond, label %for.cond.cleanup8, label %for.body9
return: ; preds = %entry, %for.cond.cleanup8
ret void
}
; Function Attrs: nounwind
declare i8* @llvm.stacksave()
; Function Attrs: nounwind
declare void @llvm.stackrestore(i8*)
; Check that llvm.stackrestore() happens before CSRs are popped off the stack
; CHECK-LABEL: f
; CHECK: stp x29, x30, [sp, #-16]!
; CHECK-NEXT: mov x29, sp
; VLA allocation
; CHECK: add [[X1:x[0-9]+]], [[X1]], #15
; CHECK: mov [[X2:x[0-9]+]], sp
; CHECK: and [[X1]], [[X1]], #0x7fffffff0
; Saving the SP via llvm.stacksave()
; CHECK: mov [[SAVE:x[0-9]+]], sp
; CHECK: sub [[X2]], [[X2]], [[X1]]
; The next instruction comes from llvm.stackrestore()
; CHECK: mov sp, [[SAVE]]
; Epilogue
; CHECK-NEXT: mov sp, x29
; CHECK-NEXT: ldp x29, x30, [sp], #16
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