1 ; RUN: llc -mtriple=x86_64-linux-gnu %s -o - -jump-table-density=25 | FileCheck %s --check-prefix=DENSE --check-prefix=CHECK 2 ; RUN: llc -mtriple=x86_64-linux-gnu %s -o - -jump-table-density=10 | FileCheck %s --check-prefix=SPARSE --check-prefix=CHECK 3 4 declare void @g(i32) 5 6 define void @sparse(i32 %x) { 7 entry: 8 switch i32 %x, label %return [ 9 i32 300, label %bb0 10 i32 100, label %bb1 11 i32 400, label %bb1 12 i32 500, label %bb2 13 ] 14 bb0: tail call void @g(i32 0) br label %return 15 bb1: tail call void @g(i32 1) br label %return 16 bb2: tail call void @g(i32 1) br label %return 17 return: ret void 18 19 ; Should pivot around 400 for two subtrees with two jump tables each. 20 ; CHECK-LABEL: sparse 21 ; CHECK-NOT: cmpl 22 ; CHECK: cmpl $399 23 ; CHECK: cmpl $100 24 ; CHECK: cmpl $300 25 ; CHECK: cmpl $400 26 ; CHECK: cmpl $500 27 } 28 29 define void @med(i32 %x) { 30 entry: 31 switch i32 %x, label %return [ 32 i32 30, label %bb0 33 i32 10, label %bb1 34 i32 40, label %bb1 35 i32 50, label %bb2 36 i32 20, label %bb3 37 ] 38 bb0: tail call void @g(i32 0) br label %return 39 bb1: tail call void @g(i32 1) br label %return 40 bb2: tail call void @g(i32 1) br label %return 41 bb3: tail call void @g(i32 2) br label %return 42 return: ret void 43 44 ; Lowered as a jump table when sparse, and branches when dense. 45 ; CHECK-LABEL: med 46 ; SPARSE: addl $-10 47 ; SPARSE: cmpl $40 48 ; SPARSE: ja 49 ; SPARSE: jmpq *.LJTI 50 ; DENSE-NOT: cmpl 51 ; DENSE: cmpl $29 52 ; DENSE-DAG: cmpl $10 53 ; DENSE-DAG: cmpl $20 54 ; DENSE-DAG: cmpl $30 55 ; DENSE-DAG: cmpl $40 56 ; DENSE-DAG: cmpl $50 57 ; DENSE: retq 58 } 59 60 define void @dense(i32 %x) { 61 entry: 62 switch i32 %x, label %return [ 63 i32 12, label %bb0 64 i32 4, label %bb1 65 i32 16, label %bb1 66 i32 20, label %bb2 67 i32 8, label %bb3 68 ] 69 bb0: tail call void @g(i32 0) br label %return 70 bb1: tail call void @g(i32 1) br label %return 71 bb2: tail call void @g(i32 1) br label %return 72 bb3: tail call void @g(i32 2) br label %return 73 return: ret void 74 75 ; Lowered as a jump table when sparse, and branches when dense. 76 ; CHECK-LABEL: dense 77 ; CHECK: addl $-4 78 ; CHECK: cmpl $16 79 ; CHECK: ja 80 ; CHECK: jmpq *.LJTI 81 } 82
