LSR fix: Add isSimplifiedLoopNest to IVUsers analysis.

Only record IVUsers that are dominated by simplified loop headers. Otherwise SCEVExpander will crash while looking for a preheader. I previously tried to work around this in LSR itself, but that was insufficient. This way, LSR can continue to run if some uses are not in simple loops, as long as we don't attempt to analyze those users. Fixes <rdar://problem/11049788> Segmentation fault: 11 in LoopStrengthReduce git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152892 91177308-0d34-0410-b5e6-96231b3b80d8
2026-04-26 12:20:42 +00:00 · 2012-03-16 03:16:56 +00:00
parent d936045625
commit 75ae20366f
6 changed files with 115 additions and 18 deletions
@@ -0,0 +1,50 @@
+; RUN: opt -loop-reduce -S < %s | FileCheck %s
+;
+; <rdar://problem/11049788> Segmentation fault: 11 in LoopStrengthReduce
+
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
+target triple = "x86_64-apple-darwin10.0.0"
+
+; IVUsers should not consider tmp128 a valid user because it is not in a
+; simplified loop nest.
+; CHECK: @nopreheader
+; CHECK: for.cond:
+; CHECK: %tmp128 = add i64 %0, %indvar65
+define void @nopreheader(i8* %cmd) nounwind ssp {
+entry:
+  indirectbr i8* undef, [label %while.cond]
+
+while.cond:                                       ; preds = %while.body, %entry
+  %0 = phi i64 [ %indvar.next48, %while.body ], [ 0, %entry ]
+  indirectbr i8* undef, [label %while.end, label %while.body]
+
+while.body:                                       ; preds = %lor.rhs, %lor.lhs.false17, %lor.lhs.false11, %lor.lhs.false, %land.rhs
+  %indvar.next48 = add i64 %0, 1
+  indirectbr i8* undef, [label %while.cond]
+
+while.end:                                        ; preds = %lor.rhs, %while.cond
+  indirectbr i8* undef, [label %if.end152]
+
+if.end152:                                        ; preds = %lor.lhs.false144, %if.end110
+  indirectbr i8* undef, [label %lor.lhs.false184, label %for.cond]
+
+lor.lhs.false184:                                 ; preds = %lor.lhs.false177
+  indirectbr i8* undef, [label %return, label %for.cond]
+
+for.cond:                                         ; preds = %for.inc, %lor.lhs.false184, %if.end152
+  %indvar65 = phi i64 [ %indvar.next66, %for.inc ], [ 0, %lor.lhs.false184 ], [ 0, %if.end152 ]
+  %tmp128 = add i64 %0, %indvar65
+  %s.4 = getelementptr i8* %cmd, i64 %tmp128
+  %tmp195 = load i8* %s.4, align 1
+  indirectbr i8* undef, [label %return, label %land.rhs198]
+
+land.rhs198:                                      ; preds = %for.cond
+  indirectbr i8* undef, [label %return, label %for.inc]
+
+for.inc:                                          ; preds = %lor.rhs234, %land.lhs.true228, %land.lhs.true216, %land.lhs.true204
+  %indvar.next66 = add i64 %indvar65, 1
+  indirectbr i8* undef, [label %for.cond]
+
+return:                                           ; preds = %if.end677, %doshell, %if.then96
+  ret void
+}