1; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py 2; RUN: llc -mtriple=riscv32 -verify-machineinstrs < %s \ 3; RUN: | FileCheck -check-prefix=RV32I %s 4 5; This test checks that LLVM can do basic stripping and reapplying of branches 6; to basic blocks. 7 8declare void @test_true() 9declare void @test_false() 10 11; !0 corresponds to a branch being taken, !1 to not being takne. 12!0 = !{!"branch_weights", i32 64, i32 4} 13!1 = !{!"branch_weights", i32 4, i32 64} 14 15define void @test_bcc_fallthrough_taken(i32 %in) nounwind { 16; RV32I-LABEL: test_bcc_fallthrough_taken: 17; RV32I: # %bb.0: 18; RV32I-NEXT: addi sp, sp, -16 19; RV32I-NEXT: sw ra, 12(sp) 20; RV32I-NEXT: addi a1, zero, 42 21; RV32I-NEXT: bne a0, a1, .LBB0_3 22; RV32I-NEXT: # %bb.1: # %true 23; RV32I-NEXT: call test_true 24; RV32I-NEXT: .LBB0_2: # %true 25; RV32I-NEXT: lw ra, 12(sp) 26; RV32I-NEXT: addi sp, sp, 16 27; RV32I-NEXT: ret 28; RV32I-NEXT: .LBB0_3: # %false 29; RV32I-NEXT: call test_false 30; RV32I-NEXT: j .LBB0_2 31 %tst = icmp eq i32 %in, 42 32 br i1 %tst, label %true, label %false, !prof !0 33 34; Expected layout order is: Entry, TrueBlock, FalseBlock 35; Entry->TrueBlock is the common path, which should be taken whenever the 36; conditional branch is false. 37 38true: 39 call void @test_true() 40 ret void 41 42false: 43 call void @test_false() 44 ret void 45} 46 47define void @test_bcc_fallthrough_nottaken(i32 %in) nounwind { 48; RV32I-LABEL: test_bcc_fallthrough_nottaken: 49; RV32I: # %bb.0: 50; RV32I-NEXT: addi sp, sp, -16 51; RV32I-NEXT: sw ra, 12(sp) 52; RV32I-NEXT: addi a1, zero, 42 53; RV32I-NEXT: beq a0, a1, .LBB1_3 54; RV32I-NEXT: # %bb.1: # %false 55; RV32I-NEXT: call test_false 56; RV32I-NEXT: .LBB1_2: # %true 57; RV32I-NEXT: lw ra, 12(sp) 58; RV32I-NEXT: addi sp, sp, 16 59; RV32I-NEXT: ret 60; RV32I-NEXT: .LBB1_3: # %true 61; RV32I-NEXT: call test_true 62; RV32I-NEXT: j .LBB1_2 63 %tst = icmp eq i32 %in, 42 64 br i1 %tst, label %true, label %false, !prof !1 65 66; Expected layout order is: Entry, FalseBlock, TrueBlock 67; Entry->FalseBlock is the common path, which should be taken whenever the 68; conditional branch is false 69 70true: 71 call void @test_true() 72 ret void 73 74false: 75 call void @test_false() 76 ret void 77} 78 79; TODO: how can we expand the coverage of the branch analysis functions? 80