Fix for PR17073 ( http://llvm.org/pr17073 ), simplifycfg illegally hoists an operatio...

[oota-llvm.git] / test / Transforms / SimplifyCFG / PR17073.ll

diff --git a/test/Transforms/SimplifyCFG/PR17073.ll b/test/Transforms/SimplifyCFG/PR17073.ll
new file mode 100644 (file)
index 0000000..8dc9fb2
--- /dev/null
+++ b/test/Transforms/SimplifyCFG/PR17073.ll
@@ -0,0 +1,73 @@
+; RUN: opt < %s -simplifycfg -S | FileCheck %s
+
+; In PR17073 ( http://llvm.org/pr17073 ), we illegally hoisted an operation that can trap.
+; The first test confirms that we don't do that when the trapping op is reached by the current BB (block1).
+; The second test confirms that we don't do that when the trapping op is reached by the previous BB (entry).
+; The third test confirms that we can still do this optimization for an operation (add) that doesn't trap.
+; The tests must be complicated enough to prevent previous SimplifyCFG actions from optimizing away
+; the instructions that we're checking for.
+
+target datalayout = "e-m:o-p:32:32-f64:32:64-f80:128-n8:16:32-S128"
+target triple = "i386-apple-macosx10.9.0"
+
+@a = common global i32 0, align 4
+@b = common global i8 0, align 1
+
+; CHECK-LABEL: can_trap1 
+; CHECK-NOT: or i1 %tobool, icmp eq (i32* bitcast (i8* @b to i32*), i32* @a)
+; CHECK-NOT: select i1 %tobool, i32* null, i32* select (i1 icmp eq (i64 urem (i64 2, i64 zext (i1 icmp eq (i32* bitcast (i8* @b to i32*), i32* @a) to i64)), i64 0), i32* null, i32* @a) 
+define i32* @can_trap1() {
+entry:
+  %0 = load i32* @a, align 4
+  %tobool = icmp eq i32 %0, 0
+  br i1 %tobool, label %exit, label %block1
+
+block1:
+  br i1 icmp eq (i32* bitcast (i8* @b to i32*), i32* @a), label %exit, label %block2
+
+block2:
+  br label %exit
+
+exit:
+  %storemerge = phi i32* [ null, %entry ],[ null, %block2 ], [ select (i1 icmp eq (i64 urem (i64 2, i64 zext (i1 icmp eq (i32* bitcast (i8* @b to i32*), i32* @a) to i64)), i64 0), i32* null, i32* @a), %block1 ]
+  ret i32* %storemerge
+}
+
+; CHECK-LABEL: can_trap2 
+; CHECK-NOT: or i1 %tobool, icmp eq (i32* bitcast (i8* @b to i32*), i32* @a)
+; CHECK-NOT: select i1 %tobool, i32* select (i1 icmp eq (i64 urem (i64 2, i64 zext (i1 icmp eq (i32* bitcast (i8* @b to i32*), i32* @a) to i64)), i64 0), i32* null, i32* @a), i32* null
+define i32* @can_trap2() {
+entry:
+  %0 = load i32* @a, align 4
+  %tobool = icmp eq i32 %0, 0
+  br i1 %tobool, label %exit, label %block1
+
+block1:
+  br i1 icmp eq (i32* bitcast (i8* @b to i32*), i32* @a), label %exit, label %block2
+
+block2:
+  br label %exit
+
+exit:
+  %storemerge = phi i32* [ select (i1 icmp eq (i64 urem (i64 2, i64 zext (i1 icmp eq (i32* bitcast (i8* @b to i32*), i32* @a) to i64)), i64 0), i32* null, i32* @a), %entry ],[ null, %block2 ], [ null, %block1 ]
+  ret i32* %storemerge
+}
+
+; CHECK-LABEL: cannot_trap 
+; CHECK: select i1 icmp eq (i32* bitcast (i8* @b to i32*), i32* @a), i32* select (i1 icmp eq (i64 add (i64 zext (i1 icmp eq (i32* bitcast (i8* @b to i32*), i32* @a) to i64), i64 2), i64 0), i32* null, i32* @a), i32* null
+define i32* @cannot_trap() {
+entry:
+  %0 = load i32* @a, align 4
+  %tobool = icmp eq i32 %0, 0
+  br i1 %tobool, label %exit, label %block1
+
+block1:
+  br i1 icmp eq (i32* bitcast (i8* @b to i32*), i32* @a), label %exit, label %block2
+
+block2:
+  br label %exit
+
+exit:
+  %storemerge = phi i32* [ null, %entry ],[ null, %block2 ], [ select (i1 icmp eq (i64 add (i64 2, i64 zext (i1 icmp eq (i32* bitcast (i8* @b to i32*), i32* @a) to i64)), i64 0), i32* null, i32* @a), %block1 ]
+  ret i32* %storemerge
+}