| ; RUN: llc -O2 -o - %s | FileCheck %s |
| target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" |
| target triple = "x86_64-unknown-linux-gnu" |
| |
| ; Function Attrs: nounwind uwtable |
| ; CHECK-LABEL: tail_dup_merge_loops |
| ; CHECK: # %entry |
| ; CHECK-NOT: # %{{[a-zA-Z_]+}} |
| ; CHECK: # %inner_loop_exit |
| ; CHECK-NOT: # %{{[a-zA-Z_]+}} |
| ; CHECK: # %inner_loop_latch |
| ; CHECK-NOT: # %{{[a-zA-Z_]+}} |
| ; CHECK: # %inner_loop_top |
| ; CHECK-NOT: # %{{[a-zA-Z_]+}} |
| ; CHECK: # %exit |
| define void @tail_dup_merge_loops(i32 %a, i8* %b, i8* %c) local_unnamed_addr #0 { |
| entry: |
| %notlhs674.i = icmp eq i32 %a, 0 |
| br label %outer_loop_top |
| |
| outer_loop_top: ; preds = %inner_loop_exit, %entry |
| %dst.0.ph.i = phi i8* [ %b, %entry ], [ %scevgep679.i, %inner_loop_exit ] |
| br i1 %notlhs674.i, label %exit, label %inner_loop_preheader |
| |
| inner_loop_preheader: ; preds = %outer_loop_top |
| br label %inner_loop_top |
| |
| inner_loop_top: ; preds = %inner_loop_latch, %inner_loop_preheader |
| %dst.0.i = phi i8* [ %inc, %inner_loop_latch ], [ %dst.0.ph.i, %inner_loop_preheader ] |
| %var = load i8, i8* %dst.0.i |
| %tobool1.i = icmp slt i8 %var, 0 |
| br label %inner_loop_test |
| |
| inner_loop_test: ; preds = %inner_loop_top |
| br i1 %tobool1.i, label %inner_loop_exit, label %inner_loop_latch |
| |
| inner_loop_exit: ; preds = %inner_loop_test |
| %scevgep.i = getelementptr i8, i8* %dst.0.i, i64 1 |
| %scevgep679.i = getelementptr i8, i8* %scevgep.i, i64 0 |
| br label %outer_loop_top |
| |
| inner_loop_latch: ; preds = %inner_loop_test |
| %cmp75.i = icmp ult i8* %dst.0.i, %c |
| %inc = getelementptr i8, i8* %dst.0.i, i64 2 |
| br label %inner_loop_top |
| |
| exit: ; preds = %outer_loop_top |
| ret void |
| } |
| |
| @.str.6 = external unnamed_addr constant [23 x i8], align 1 |
| |
| ; There is an erroneus check in LoopBase::addBasicBlockToLoop(), where it |
| ; assumes that the header block for a loop is unique. |
| ; For most of compilation this assumption is true, but during layout we allow |
| ; this assumption to be violated. The following code will trigger the bug: |
| |
| ; The loops in question is eventually headed by the block shared_loop_header |
| ; |
| ; During layout The block labeled outer_loop_header gets tail-duplicated into |
| ; outer_loop_latch, and into shared_preheader, and then removed. This leaves |
| ; shared_loop_header as the header of both loops. The end result |
| ; is that there are 2 valid loops, and that they share a header. If we re-ran |
| ; the loop analysis, it would classify this as a single loop. |
| ; So far this is fine as far as layout is concerned. |
| ; After layout we tail merge blocks merge_other and merge_predecessor_split. |
| ; We do this even though they share only a single instruction, because |
| ; merge_predecessor_split falls through to their shared successor: |
| ; outer_loop_latch. |
| ; The rest of the blocks in the function are noise unfortunately. Bugpoint |
| ; couldn't shrink the test any further. |
| |
| ; CHECK-LABEL: loop_shared_header |
| ; CHECK: # %entry |
| ; CHECK: # %shared_preheader |
| ; CHECK: # %shared_loop_header |
| ; CHECK: # %inner_loop_body |
| ; CHECK: # %outer_loop_latch |
| ; CHECK: # %merge_predecessor_split |
| ; CHECK: # %outer_loop_latch |
| ; CHECK: # %cleanup |
| define i32 @loop_shared_header(i8* %exe, i32 %exesz, i32 %headsize, i32 %min, i32 %wwprva, i32 %e_lfanew, i8* readonly %wwp, i32 %wwpsz, i16 zeroext %sects) local_unnamed_addr #0 { |
| entry: |
| %0 = load i32, i32* undef, align 4 |
| %mul = shl nsw i32 %0, 2 |
| br i1 undef, label %if.end19, label %cleanup |
| |
| if.end19: ; preds = %entry |
| %conv = zext i32 %mul to i64 |
| %call = tail call i8* @cli_calloc(i64 %conv, i64 1) |
| %1 = icmp eq i32 %exesz, 0 |
| %notrhs = icmp eq i32 %0, 0 |
| %or.cond117.not = or i1 %1, %notrhs |
| %or.cond202 = or i1 %or.cond117.not, undef |
| %cmp35 = icmp ult i8* undef, %exe |
| %or.cond203 = or i1 %or.cond202, %cmp35 |
| br i1 %or.cond203, label %cleanup, label %if.end50 |
| |
| if.end50: ; preds = %if.end19 |
| tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* nonnull %call, i8* undef, i64 %conv, i1 false) |
| %cmp1.i.i = icmp ugt i32 %mul, 3 |
| br i1 %cmp1.i.i, label %shared_preheader, label %wunpsect.exit.thread.loopexit391 |
| |
| shared_preheader: ; preds = %if.end50 |
| br label %outer_loop_header |
| |
| outer_loop_header: ; preds = %outer_loop_latch, %shared_preheader |
| %bits.1.i = phi i8 [ 32, %shared_preheader ], [ %bits.43.i, %outer_loop_latch ] |
| %dst.0.ph.i = phi i8* [ undef, %shared_preheader ], [ %scevgep679.i, %outer_loop_latch ] |
| %2 = icmp eq i32 undef, 0 |
| br i1 %2, label %while.cond.us1412.i, label %shared_loop_header |
| |
| while.cond.us1412.i: ; preds = %outer_loop_header |
| %.pre.i = add i8 %bits.1.i, -1 |
| %tobool2.us1420.i = icmp eq i8 %.pre.i, 0 |
| %or.cond.us1421.i = or i1 undef, %tobool2.us1420.i |
| br i1 %or.cond.us1421.i, label %if.end41.us1436.i, label %cleanup |
| |
| if.end41.us1436.i: ; preds = %while.cond.us1412.i |
| unreachable |
| |
| shared_loop_header: ; preds = %dup_early2, %dup_early1 |
| %dst.0.i = phi i8* [ undef, %inner_loop_body ], [ %dst.0.ph.i, %outer_loop_header ], [ undef, %dead_block ] |
| %cmp3.i1172.i = icmp ult i8* undef, %call |
| br i1 %cmp3.i1172.i, label %wunpsect.exit.thread.loopexit389, label %inner_loop_body |
| |
| inner_loop_body: ; preds = %shared_loop_header |
| %3 = icmp slt i32 undef, 0 |
| br i1 %3, label %if.end96.i, label %shared_loop_header |
| |
| dead_block: ; preds = %inner_loop_body |
| %cmp75.i = icmp ult i8* %dst.0.i, undef |
| br label %shared_loop_header |
| |
| if.end96.i: ; preds = %inner_loop_body |
| %cmp97.i = icmp ugt i32 undef, 2 |
| br i1 %cmp97.i, label %if.then99.i, label %if.end287.i |
| |
| if.then99.i: ; preds = %if.end96.i |
| tail call void (i8*, ...) @cli_dbgmsg(i8* getelementptr inbounds ([23 x i8], [23 x i8]* @.str.6, i64 0, i64 0), i32 undef) |
| br label %cleanup |
| |
| if.end287.i: ; preds = %if.end96.i |
| %cmp291.i = icmp ne i32 undef, 1 |
| %conv294.i = select i1 %cmp291.i, i16 4, i16 3 |
| br i1 undef, label %if.end308.i, label %outer_loop_latch |
| |
| if.end308.i: ; preds = %if.end287.i |
| br i1 undef, label %if.end335.i, label %merge_predecessor_split |
| |
| merge_predecessor_split: ; preds = %if.end308.i |
| %4 = bitcast i8* undef to i32* |
| br label %outer_loop_latch |
| |
| if.end335.i: ; preds = %if.end308.i |
| br i1 undef, label %outer_loop_latch, label %merge_other |
| |
| merge_other: ; preds = %if.end335.i |
| br label %outer_loop_latch |
| |
| outer_loop_latch: ; preds = %merge_other, %if.end335.i, %merge_predecessor_split, %if.end287.i |
| %bits.43.i = phi i8 [ undef, %if.end287.i ], [ undef, %merge_other ], [ 32, %merge_predecessor_split ], [ 0, %if.end335.i ] |
| %backsize.0.i = phi i16 [ %conv294.i, %if.end287.i ], [ 0, %merge_other ], [ 0, %merge_predecessor_split ], [ 0, %if.end335.i ] |
| %5 = add i16 %backsize.0.i, -1 |
| %6 = zext i16 %5 to i64 |
| %scevgep.i = getelementptr i8, i8* %dst.0.ph.i, i64 1 |
| %scevgep679.i = getelementptr i8, i8* %scevgep.i, i64 %6 |
| br label %outer_loop_header |
| |
| wunpsect.exit.thread.loopexit389: ; preds = %shared_loop_header |
| unreachable |
| |
| wunpsect.exit.thread.loopexit391: ; preds = %if.end50 |
| unreachable |
| |
| cleanup: ; preds = %if.then99.i, %while.cond.us1412.i, %if.end19, %entry |
| %retval.0 = phi i32 [ 0, %if.then99.i ], [ 1, %entry ], [ 1, %if.end19 ], [ 1, %while.cond.us1412.i ] |
| ret i32 %retval.0 |
| } |
| |
| ; Function Attrs: nounwind |
| declare void @cli_dbgmsg(i8*, ...) local_unnamed_addr #0 |
| |
| ; Function Attrs: nounwind |
| declare i8* @cli_calloc(i64, i64) local_unnamed_addr #0 |
| |
| ; Function Attrs: argmemonly nounwind |
| declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture writeonly, i8* nocapture readonly, i64, i1) #1 |
| attributes #0 = { nounwind } |
| attributes #1 = { argmemonly nounwind } |
