95 lines · plain
1; Test shrink wrapping placement is correct with respect to calls to llvm.{stacksave,stackrestore}2 3; void f(int n, int x[]) {4; if (n < 0)5; return;6;7; int a[n];8;9; for (int i = 0; i < n; i++)10; a[i] = x[n - i - 1];11;12; for (int i = 0; i < n; i++)13; x[i] = a[i] + 1;14; }15;16; RUN: llc -mtriple x86_64-linux %s -o - | FileCheck %s --check-prefix=CHECK17 18define dso_local void @f(i32 %n, ptr nocapture %x) {19entry:20 %cmp = icmp slt i32 %n, 021 br i1 %cmp, label %return, label %if.end22 23if.end: ; preds = %entry24 %0 = zext i32 %n to i6425 %1 = tail call ptr @llvm.stacksave()26 %vla = alloca i32, i64 %0, align 1627 %cmp132 = icmp eq i32 %n, 028 br i1 %cmp132, label %for.cond.cleanup8, label %for.body.lr.ph29 30for.body.lr.ph: ; preds = %if.end31 %sub = add i32 %n, -132 br label %for.body33 34for.cond6.preheader: ; preds = %for.body35 %cmp730 = icmp sgt i32 %n, 036 br i1 %cmp730, label %for.body9, label %for.cond.cleanup837 38for.body: ; preds = %for.body, %for.body.lr.ph39 %indvars.iv34 = phi i64 [ 0, %for.body.lr.ph ], [ %indvars.iv.next35, %for.body ]40 %2 = trunc i64 %indvars.iv34 to i3241 %sub2 = sub i32 %sub, %242 %idxprom = sext i32 %sub2 to i6443 %arrayidx = getelementptr inbounds i32, ptr %x, i64 %idxprom44 %3 = load i32, ptr %arrayidx, align 445 %arrayidx4 = getelementptr inbounds i32, ptr %vla, i64 %indvars.iv3446 store i32 %3, ptr %arrayidx4, align 447 %indvars.iv.next35 = add nuw nsw i64 %indvars.iv34, 148 %exitcond37 = icmp eq i64 %indvars.iv.next35, %049 br i1 %exitcond37, label %for.cond6.preheader, label %for.body50 51for.cond.cleanup8: ; preds = %for.body9, %if.end, %for.cond6.preheader52 tail call void @llvm.stackrestore(ptr %1)53 br label %return54 55for.body9: ; preds = %for.cond6.preheader, %for.body956 %indvars.iv = phi i64 [ %indvars.iv.next, %for.body9 ], [ 0, %for.cond6.preheader ]57 %arrayidx11 = getelementptr inbounds i32, ptr %vla, i64 %indvars.iv58 %4 = load i32, ptr %arrayidx11, align 459 %add = add nsw i32 %4, 160 %arrayidx13 = getelementptr inbounds i32, ptr %x, i64 %indvars.iv61 store i32 %add, ptr %arrayidx13, align 462 %indvars.iv.next = add nuw nsw i64 %indvars.iv, 163 %exitcond = icmp eq i64 %indvars.iv.next, %064 br i1 %exitcond, label %for.cond.cleanup8, label %for.body965 66return: ; preds = %entry, %for.cond.cleanup867 ret void68}69 70; Function Attrs: nounwind71declare ptr @llvm.stacksave()72 73; Function Attrs: nounwind74declare void @llvm.stackrestore(ptr)75 76; Check that llvm.stackrestore() happens before CSRs are popped off the stack77 78; CHECK-LABEL: f79 80; CHECK: pushq %rbp81; CHECK: movq %rsp, %rbp82 83; Saving the SP via llvm.stacksave()84; CHECK: movq %rsp, [[SAVE:%r[a-z0-9]+]]85; VLA allocation86; CHECK: movq %rsp, [[TMP:%r[a-z0-9]+]]87; CHECK: subq %r{{[a-z0-9]+}}, [[TMP]]88; CHECK: movq [[TMP]], %rsp89 90; The next instruction comes from llvm.stackrestore()91; CHECK: movq [[SAVE]], %rsp92; Epilogue93; CHECK-NEXT: movq %rbp, %rsp94; CHECK-NEXT: popq %rbp95