1 ; RUN: opt < %s -simplifycfg -S | FileCheck %s 2 3 ; In PR17073 ( http://llvm.org/pr17073 ), we illegally hoisted an operation that can trap. 4 ; The first test confirms that we don't do that when the trapping op is reached by the current BB (block1). 5 ; The second test confirms that we don't do that when the trapping op is reached by the previous BB (entry). 6 ; The third test confirms that we can still do this optimization for an operation (add) that doesn't trap. 7 ; The tests must be complicated enough to prevent previous SimplifyCFG actions from optimizing away 8 ; the instructions that we're checking for. 9 10 target datalayout = "e-m:o-p:32:32-f64:32:64-f80:128-n8:16:32-S128" 11 target triple = "i386-apple-macosx10.9.0" 12 13 @a = common global i32 0, align 4 14 @b = common global i8 0, align 1 15 16 ; CHECK-LABEL: can_trap1 17 ; CHECK-NOT: or i1 %tobool, icmp eq (i32* bitcast (i8* @b to i32*), i32* @a) 18 ; 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) 19 define i32* @can_trap1() { 20 entry: 21 %0 = load i32* @a, align 4 22 %tobool = icmp eq i32 %0, 0 23 br i1 %tobool, label %exit, label %block1 24 25 block1: 26 br i1 icmp eq (i32* bitcast (i8* @b to i32*), i32* @a), label %exit, label %block2 27 28 block2: 29 br label %exit 30 31 exit: 32 %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 ] 33 ret i32* %storemerge 34 } 35 36 ; CHECK-LABEL: can_trap2 37 ; CHECK-NOT: or i1 %tobool, icmp eq (i32* bitcast (i8* @b to i32*), i32* @a) 38 ; 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 39 define i32* @can_trap2() { 40 entry: 41 %0 = load i32* @a, align 4 42 %tobool = icmp eq i32 %0, 0 43 br i1 %tobool, label %exit, label %block1 44 45 block1: 46 br i1 icmp eq (i32* bitcast (i8* @b to i32*), i32* @a), label %exit, label %block2 47 48 block2: 49 br label %exit 50 51 exit: 52 %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 ] 53 ret i32* %storemerge 54 } 55 56 ; CHECK-LABEL: cannot_trap 57 ; 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 58 define i32* @cannot_trap() { 59 entry: 60 %0 = load i32* @a, align 4 61 %tobool = icmp eq i32 %0, 0 62 br i1 %tobool, label %exit, label %block1 63 64 block1: 65 br i1 icmp eq (i32* bitcast (i8* @b to i32*), i32* @a), label %exit, label %block2 66 67 block2: 68 br label %exit 69 70 exit: 71 %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 ] 72 ret i32* %storemerge 73 } 74
