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; Checks generated using command:
; llvm/utils/update_test_body.py llvm/test/CodeGen/BPF/jump_table_blockaddr.ll
; RUN: rm -rf %t && split-file %s %t && cd %t
; RUN: llc -march=bpf -mcpu=v4 < test.ll | FileCheck %s
;
; Source code:
; int bar(int a) {
; __label__ l1, l2;
; void * volatile tgt;
; int ret = 0;
; if (a)
; tgt = &&l1; // synthetic jump table generated here
; else
; tgt = &&l2; // another synthetic jump table
; goto *tgt;
; l1: ret += 1;
; l2: ret += 2;
; return ret;
; }
;
; Compilation Flags:
; clang --target=bpf -mcpu=v4 -O2 -emit-llvm -S test.c
.ifdef GEN
;--- test.ll
define dso_local range(i32 2, 4) i32 @bar(i32 noundef %a) local_unnamed_addr{
entry:
%tgt = alloca ptr, align 8
%tobool.not = icmp eq i32 %a, 0
%. = select i1 %tobool.not, ptr blockaddress(@bar, %l2), ptr blockaddress(@bar, %l1)
store volatile ptr %., ptr %tgt, align 8
%tgt.0.tgt.0.tgt.0.tgt.0. = load volatile ptr, ptr %tgt, align 8
indirectbr ptr %tgt.0.tgt.0.tgt.0.tgt.0., [label %l1, label %l2]
l1: ; preds = %entry
br label %l2
l2: ; preds = %l1, %entry
%ret.0 = phi i32 [ 3, %l1 ], [ 2, %entry ]
ret i32 %ret.0
}
;--- gen
echo ""
echo "; Generated checks follow"
echo ";"
llc -march=bpf -mcpu=v4 < test.ll \
| awk '/# -- End function/ {p=0} /@function/ {p=1} p {print "; CHECK" ": " $0}'
.endif
; Generated checks follow
;
; CHECK: .type bar,@function
; CHECK: bar: # @bar
; CHECK: .Lbar$local:
; CHECK: .type .Lbar$local,@function
; CHECK: .cfi_startproc
; CHECK: # %bb.0: # %entry
; CHECK: r2 = BPF.JT.0.0 ll
; CHECK: r2 = *(u64 *)(r2 + 0)
; CHECK: r3 = BPF.JT.0.1 ll
; CHECK: r3 = *(u64 *)(r3 + 0)
; CHECK: if w1 == 0 goto LBB0_2
; CHECK: # %bb.1: # %entry
; CHECK: r3 = r2
; CHECK: LBB0_2: # %entry
; CHECK: *(u64 *)(r10 - 8) = r3
; CHECK: r1 = *(u64 *)(r10 - 8)
; CHECK: gotox r1
; CHECK: .Ltmp0: # Block address taken
; CHECK: LBB0_3: # %l1
; CHECK: w0 = 3
; CHECK: goto LBB0_5
; CHECK: .Ltmp1: # Block address taken
; CHECK: LBB0_4: # %l2
; CHECK: w0 = 2
; CHECK: LBB0_5: # %.split
; CHECK: exit
; CHECK: .Lfunc_end0:
; CHECK: .size bar, .Lfunc_end0-bar
; CHECK: .size .Lbar$local, .Lfunc_end0-bar
; CHECK: .cfi_endproc
; CHECK: .section .jumptables,"",@progbits
; CHECK: BPF.JT.0.0:
; CHECK: .quad LBB0_3
; CHECK: .size BPF.JT.0.0, 8
; CHECK: BPF.JT.0.1:
; CHECK: .quad LBB0_4
; CHECK: .size BPF.JT.0.1, 8
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