[llvm] r306985 - [InstCombine] fix crash when folding cmp+bswap vector

[Sanjay Patel via llvm-commits]

Author: spatel
Date: Sun Jul  2 09:05:11 2017
New Revision: 306985

URL: http://llvm.org/viewvc/llvm-project?rev=306985&view=rev
Log:
[InstCombine] fix crash when folding cmp+bswap vector

We assumed the constant was a scalar when creating the replacement operand.

Also, improve tests for this fold and move the tests for this fold to their own file.
I'll move the related and missing tests to this file as a follow-up.  

Added:
    llvm/trunk/test/Transforms/InstCombine/cmp-intrinsic.ll
Modified:
    llvm/trunk/lib/Transforms/InstCombine/InstCombineCompares.cpp
    llvm/trunk/test/Transforms/InstCombine/bswap-fold.ll

Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombineCompares.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombineCompares.cpp?rev=306985&r1=306984&r2=306985&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombineCompares.cpp (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombineCompares.cpp Sun Jul  2 09:05:11 2017
@@ -2740,23 +2740,26 @@ Instruction *InstCombiner::foldICmpIntri
   if (!II || !Cmp.isEquality())
     return nullptr;
 
-  // Handle icmp {eq|ne} <intrinsic>, intcst.
+  // Handle icmp {eq|ne} <intrinsic>, Constant.
+  Type *Ty = II->getType();
   switch (II->getIntrinsicID()) {
   case Intrinsic::bswap:
     Worklist.Add(II);
     Cmp.setOperand(0, II->getArgOperand(0));
-    Cmp.setOperand(1, Builder->getInt(C->byteSwap()));
+    Cmp.setOperand(1, ConstantInt::get(Ty, C->byteSwap()));
     return &Cmp;
+
   case Intrinsic::ctlz:
   case Intrinsic::cttz:
     // ctz(A) == bitwidth(A)  ->  A == 0 and likewise for !=
     if (*C == C->getBitWidth()) {
       Worklist.Add(II);
       Cmp.setOperand(0, II->getArgOperand(0));
-      Cmp.setOperand(1, ConstantInt::getNullValue(II->getType()));
+      Cmp.setOperand(1, ConstantInt::getNullValue(Ty));
       return &Cmp;
     }
     break;
+
   case Intrinsic::ctpop: {
     // popcount(A) == 0  ->  A == 0 and likewise for !=
     // popcount(A) == bitwidth(A)  ->  A == -1 and likewise for !=
@@ -2764,8 +2767,8 @@ Instruction *InstCombiner::foldICmpIntri
     if (IsZero || *C == C->getBitWidth()) {
       Worklist.Add(II);
       Cmp.setOperand(0, II->getArgOperand(0));
-      auto *NewOp = IsZero ? Constant::getNullValue(II->getType())
-                           : Constant::getAllOnesValue(II->getType());
+      auto *NewOp =
+          IsZero ? Constant::getNullValue(Ty) : Constant::getAllOnesValue(Ty);
       Cmp.setOperand(1, NewOp);
       return &Cmp;
     }
@@ -2774,6 +2777,7 @@ Instruction *InstCombiner::foldICmpIntri
   default:
     break;
   }
+
   return nullptr;
 }
 

Modified: llvm/trunk/test/Transforms/InstCombine/bswap-fold.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/bswap-fold.ll?rev=306985&r1=306984&r2=306985&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/InstCombine/bswap-fold.ll (original)
+++ llvm/trunk/test/Transforms/InstCombine/bswap-fold.ll Sun Jul  2 09:05:11 2017
@@ -1,35 +1,5 @@
 ; RUN: opt < %s -instcombine -S | FileCheck %s
 
-define i1 @test1(i16 %t) {
-; CHECK-LABEL: @test1(
-; CHECK-NEXT:    [[TMP2:%.*]] = icmp eq i16 %t, 256
-; CHECK-NEXT:    ret i1 [[TMP2]]
-;
-  %tmp1 = call i16 @llvm.bswap.i16( i16 %t )
-  %tmp2 = icmp eq i16 %tmp1, 1
-  ret i1 %tmp2
-}
-
-define i1 @test2(i32 %tmp) {
-; CHECK-LABEL: @test2(
-; CHECK-NEXT:    [[TMP_UPGRD_1:%.*]] = icmp eq i32 %tmp, 16777216
-; CHECK-NEXT:    ret i1 [[TMP_UPGRD_1]]
-;
-  %tmp34 = tail call i32 @llvm.bswap.i32( i32 %tmp )
-  %tmp.upgrd.1 = icmp eq i32 %tmp34, 1
-  ret i1 %tmp.upgrd.1
-}
-
-define i1 @test3(i64 %tmp) {
-; CHECK-LABEL: @test3(
-; CHECK-NEXT:    [[TMP_UPGRD_2:%.*]] = icmp eq i64 %tmp, 72057594037927936
-; CHECK-NEXT:    ret i1 [[TMP_UPGRD_2]]
-;
-  %tmp34 = tail call i64 @llvm.bswap.i64( i64 %tmp )
-  %tmp.upgrd.2 = icmp eq i64 %tmp34, 1
-  ret i1 %tmp.upgrd.2
-}
-
 ; rdar://5992453
 ; A & 255
 define i32 @test4(i32 %a) nounwind  {

Added: llvm/trunk/test/Transforms/InstCombine/cmp-intrinsic.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/cmp-intrinsic.ll?rev=306985&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/InstCombine/cmp-intrinsic.ll (added)
+++ llvm/trunk/test/Transforms/InstCombine/cmp-intrinsic.ll Sun Jul  2 09:05:11 2017
@@ -0,0 +1,36 @@
+; RUN: opt < %s -instcombine -S | FileCheck %s
+
+declare i16 @llvm.bswap.i16(i16)
+declare i32 @llvm.bswap.i32(i32)
+declare <2 x i64> @llvm.bswap.v2i64(<2 x i64>)
+
+define i1 @bswap_eq_i16(i16 %x) {
+; CHECK-LABEL: @bswap_eq_i16(
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i16 %x, 256
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %bs = call i16 @llvm.bswap.i16(i16 %x)
+  %cmp = icmp eq i16 %bs, 1
+  ret i1 %cmp
+}
+
+define i1 @bswap_ne_i32(i32 %x) {
+; CHECK-LABEL: @bswap_ne_i32(
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ne i32 %x, 33554432
+; CHECK-NEXT:    ret i1 [[CMP]]
+;
+  %bs = tail call i32 @llvm.bswap.i32(i32 %x)
+  %cmp = icmp ne i32 %bs, 2
+  ret i1 %cmp
+}
+
+define <2 x i1> @bswap_eq_v2i64(<2 x i64> %x) {
+; CHECK-LABEL: @bswap_eq_v2i64(
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq <2 x i64> %x, <i64 216172782113783808, i64 216172782113783808>
+; CHECK-NEXT:    ret <2 x i1> [[CMP]]
+;
+  %bs = tail call <2 x i64> @llvm.bswap.v2i64(<2 x i64> %x)
+  %cmp = icmp eq <2 x i64> %bs, <i64 3, i64 3>
+  ret <2 x i1> %cmp
+}
+