; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py ; RUN: llc < %s -mtriple=i686-- -O3 -verify-machineinstrs | FileCheck %s ; Tests for using callbr as an asm-goto wrapper ; Test 1 - fallthrough label gets removed, but the fallthrough code that is ; unreachable due to asm ending on a jmp is still left in. define i32 @test1(i32 %a) { ; CHECK-LABEL: test1: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: movl {{[0-9]+}}(%esp), %eax ; CHECK-NEXT: addl $4, %eax ; CHECK-NEXT: #APP ; CHECK-NEXT: xorl %eax, %eax ; CHECK-NEXT: jmp .Ltmp0 ; CHECK-NEXT: #NO_APP ; CHECK-NEXT: # %bb.1: # %normal ; CHECK-NEXT: xorl %eax, %eax ; CHECK-NEXT: retl ; CHECK-NEXT: .Ltmp0: # Block address taken ; CHECK-NEXT: .LBB0_2: # %fail ; CHECK-NEXT: movl $1, %eax ; CHECK-NEXT: retl entry: %0 = add i32 %a, 4 callbr void asm "xorl $0, $0; jmp ${1:l}", "r,X,~{dirflag},~{fpsr},~{flags}"(i32 %0, i8* blockaddress(@test1, %fail)) to label %normal [label %fail] normal: ret i32 0 fail: ret i32 1 } ; Test 2 - callbr terminates an unreachable block, function gets simplified ; to a trivial zero return. define i32 @test2(i32 %a) { ; CHECK-LABEL: test2: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: xorl %eax, %eax ; CHECK-NEXT: retl entry: br label %normal unreachableasm: %0 = add i32 %a, 4 callbr void asm sideeffect "xorl $0, $0; jmp ${1:l}", "r,X,~{dirflag},~{fpsr},~{flags}"(i32 %0, i8* blockaddress(@test2, %fail)) to label %normal [label %fail] normal: ret i32 0 fail: ret i32 1 } ; Test 3 - asm-goto implements a loop. The loop gets recognized, but many loop ; transforms fail due to canonicalization having callbr exceptions. Trivial ; blocks at labels 1 and 3 also don't get simplified due to callbr. define i32 @test3(i32 %a) { ; CHECK-LABEL: test3: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: .Ltmp1: # Block address taken ; CHECK-NEXT: .LBB2_1: # %label01 ; CHECK-NEXT: # =>This Loop Header: Depth=1 ; CHECK-NEXT: # Child Loop BB2_2 Depth 2 ; CHECK-NEXT: # Child Loop BB2_3 Depth 3 ; CHECK-NEXT: # Child Loop BB2_4 Depth 4 ; CHECK-NEXT: .Ltmp2: # Block address taken ; CHECK-NEXT: .LBB2_2: # %label02 ; CHECK-NEXT: # Parent Loop BB2_1 Depth=1 ; CHECK-NEXT: # => This Loop Header: Depth=2 ; CHECK-NEXT: # Child Loop BB2_3 Depth 3 ; CHECK-NEXT: # Child Loop BB2_4 Depth 4 ; CHECK-NEXT: addl $4, {{[0-9]+}}(%esp) ; CHECK-NEXT: .Ltmp3: # Block address taken ; CHECK-NEXT: .LBB2_3: # %label03 ; CHECK-NEXT: # Parent Loop BB2_1 Depth=1 ; CHECK-NEXT: # Parent Loop BB2_2 Depth=2 ; CHECK-NEXT: # => This Loop Header: Depth=3 ; CHECK-NEXT: # Child Loop BB2_4 Depth 4 ; CHECK-NEXT: .Ltmp4: # Block address taken ; CHECK-NEXT: .LBB2_4: # %label04 ; CHECK-NEXT: # Parent Loop BB2_1 Depth=1 ; CHECK-NEXT: # Parent Loop BB2_2 Depth=2 ; CHECK-NEXT: # Parent Loop BB2_3 Depth=3 ; CHECK-NEXT: # => This Inner Loop Header: Depth=4 ; CHECK-NEXT: #APP ; CHECK-NEXT: jmp .Ltmp1 ; CHECK-NEXT: jmp .Ltmp2 ; CHECK-NEXT: jmp .Ltmp3 ; CHECK-NEXT: #NO_APP ; CHECK-NEXT: # %bb.5: # %normal0 ; CHECK-NEXT: # in Loop: Header=BB2_4 Depth=4 ; CHECK-NEXT: #APP ; CHECK-NEXT: jmp .Ltmp1 ; CHECK-NEXT: jmp .Ltmp2 ; CHECK-NEXT: jmp .Ltmp3 ; CHECK-NEXT: jmp .Ltmp4 ; CHECK-NEXT: #NO_APP ; CHECK-NEXT: # %bb.6: # %normal1 ; CHECK-NEXT: movl {{[0-9]+}}(%esp), %eax ; CHECK-NEXT: retl entry: %a.addr = alloca i32, align 4 store i32 %a, i32* %a.addr, align 4 br label %label01 label01: ; preds = %normal0, %label04, %entry br label %label02 label02: ; preds = %normal0, %label04, %label01 %0 = load i32, i32* %a.addr, align 4 %add = add nsw i32 %0, 4 store i32 %add, i32* %a.addr, align 4 br label %label03 label03: ; preds = %normal0, %label04, %label02 br label %label04 label04: ; preds = %normal0, %label03 callbr void asm sideeffect "jmp ${0:l}; jmp ${1:l}; jmp ${2:l}", "X,X,X,~{dirflag},~{fpsr},~{flags}"(i8* blockaddress(@test3, %label01), i8* blockaddress(@test3, %label02), i8* blockaddress(@test3, %label03)) to label %normal0 [label %label01, label %label02, label %label03] normal0: ; preds = %label04 callbr void asm sideeffect "jmp ${0:l}; jmp ${1:l}; jmp ${2:l}; jmp ${3:l}", "X,X,X,X,~{dirflag},~{fpsr},~{flags}"(i8* blockaddress(@test3, %label01), i8* blockaddress(@test3, %label02), i8* blockaddress(@test3, %label03), i8* blockaddress(@test3, %label04)) to label %normal1 [label %label01, label %label02, label %label03, label %label04] normal1: ; preds = %normal0 %1 = load i32, i32* %a.addr, align 4 ret i32 %1 } ; Test 4 - asm-goto referenced with the 'l' (ell) modifier and not. define void @test4() { ; CHECK-LABEL: test4: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: #APP ; CHECK-NEXT: ja .Ltmp5 ; CHECK-NEXT: #NO_APP ; CHECK-NEXT: # %bb.1: # %asm.fallthrough ; CHECK-NEXT: #APP ; CHECK-NEXT: ja .Ltmp5 ; CHECK-NEXT: #NO_APP ; CHECK-NEXT: .Ltmp5: # Block address taken ; CHECK-NEXT: .LBB3_3: # %quux ; CHECK-NEXT: retl entry: callbr void asm sideeffect "ja $0", "X,~{dirflag},~{fpsr},~{flags}"(i8* blockaddress(@test4, %quux)) to label %asm.fallthrough [label %quux] asm.fallthrough: ; preds = %entry callbr void asm sideeffect "ja ${0:l}", "X,~{dirflag},~{fpsr},~{flags}"(i8* blockaddress(@test4, %quux)) to label %cleanup [label %quux] quux: ; preds = %asm.fallthrough, %entry br label %cleanup cleanup: ; preds = %asm.fallthrough, %quux ret void }