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1; RUN: llc -mtriple=bpfel -mcpu=v4 -gotol-abs-low-bound 0 -verify-machineinstrs -show-mc-encoding < %s | FileCheck %s2; Source:3; // This test covers all three cases:4; // (1). jmp to another basic block (not the follow-through one)5; // (2). conditional jmp (follow-through and non-follow-through)6; // (3). conditional jmp followed by an unconditional jmp7; // To trigger case (3) the following code is developed which8; // covers case (1) and (2) as well.9; unsigned foo(unsigned a, unsigned b) {10; unsigned s = b;11; if (a < b)12; goto next;13; else14; goto next2;15; begin:16; s /= b;17; if (s > a)18; return s * s;19; next:20; s *= a;21; if (s > b)22; goto begin;23; next2:24; s *= b;25; if (s > a)26; goto begin;27; return s;28; }29; Compilation flags:30; clang -target bpf -O2 -mcpu=v4 -S -emit-llvm t.c31 32; Function Attrs: nofree norecurse nosync nounwind memory(none)33define dso_local i32 @foo(i32 noundef %a, i32 noundef %b) local_unnamed_addr #0 {34entry:35 %cmp = icmp ult i32 %a, %b36 br i1 %cmp, label %next, label %next237 38; case (3): conditional jmp followed by an unconditional jmp39; CHECK: w0 = w240; CHECK-NEXT: if w1 < w2 goto41; CHECK: gotol LBB0_4 # encoding: [0x06'A',A,A,A,0x00,0x00,0x00,0x00]42; CHECK-NEXT: # fixup A - offset: 0, value: LBB0_4, kind: FK_BPF_PCRel_443 44begin: ; preds = %next2, %next45 %s.0 = phi i32 [ %mul3, %next ], [ %mul7, %next2 ]46 %div = udiv i32 %s.0, %b47 %cmp1 = icmp ugt i32 %div, %a48 br i1 %cmp1, label %if.then2, label %next49 50; case (2): conditional jmp51; CHECK: w0 *= w152; CHECK-NEXT: if w0 > w2 goto LBB0_753; CHECK: goto LBB0_454; CHECK-LABEL: LBB0_7:55; CHECK: gotol56 57; CHECK-LABEL: LBB0_4:58 59if.then2: ; preds = %begin60 %mul = mul i32 %div, %div61 br label %cleanup62 63; case (1): unconditional jmp64; CHECK: w0 *= w065; CHECK-NEXT: gotol66 67next: ; preds = %begin, %entry68 %s.1 = phi i32 [ %b, %entry ], [ %div, %begin ]69 %mul3 = mul i32 %s.1, %a70 %cmp4 = icmp ugt i32 %mul3, %b71 br i1 %cmp4, label %begin, label %next272 73next2: ; preds = %next, %entry74 %s.2 = phi i32 [ %mul3, %next ], [ %b, %entry ]75 %mul7 = mul i32 %s.2, %b76 %cmp8 = icmp ugt i32 %mul7, %a77 br i1 %cmp8, label %begin, label %cleanup78 79cleanup: ; preds = %next2, %if.then280 %retval.0 = phi i32 [ %mul, %if.then2 ], [ %mul7, %next2 ]81 ret i32 %retval.082}83 84attributes #0 = { nofree norecurse nosync nounwind memory(none) "frame-pointer"="all" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="v4" }85 86!llvm.module.flags = !{!0, !1}87!llvm.ident = !{!2}88 89!0 = !{i32 1, !"wchar_size", i32 4}90!1 = !{i32 7, !"frame-pointer", i32 2}91!2 = !{!"clang version 18.0.0 (https://github.com/llvm/llvm-project.git dccf0f74657ce8c50eb1e997bae356c32d7b1ffe)"}92