From 480fc70c4333e1655e9fe137e72ba8a8229316b8 Mon Sep 17 00:00:00 2001
From: Wei Mi <wmi@google.com>
Date: Tue, 21 Apr 2015 22:56:09 +0000
Subject: [PATCH] Revert r235451 since it is attached to a wrong Differential
 Revision. Sorry.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235453 91177308-0d34-0410-b5e6-96231b3b80d8
---
 .../InstCombine/InstructionCombining.cpp      |  5 --
 test/Transforms/InstCombine/descale-zero.ll   | 20 ++++++++
 test/Transforms/InstCombine/gep-merge.ll      | 48 -------------------
 test/Transforms/InstCombine/getelementptr.ll  |  4 +-
 4 files changed, 22 insertions(+), 55 deletions(-)
 create mode 100644 test/Transforms/InstCombine/descale-zero.ll
 delete mode 100644 test/Transforms/InstCombine/gep-merge.ll

diff --git a/lib/Transforms/InstCombine/InstructionCombining.cpp b/lib/Transforms/InstCombine/InstructionCombining.cpp
index f62941fbf64..3b46156c1ab 100644
--- a/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -1467,11 +1467,6 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
         // normalized.
         if (SO1->getType() != GO1->getType())
           return nullptr;
-        // Only do the combine when GO1 and SO1 are both constants. Only in
-        // this case, we are sure the cost after the merge is never more than
-        // that before the merge.
-        if (!isa<Constant>(GO1) || !isa<Constant>(SO1))
-          return nullptr;
         Sum = Builder->CreateAdd(SO1, GO1, PtrOp->getName()+".sum");
       }
 
diff --git a/test/Transforms/InstCombine/descale-zero.ll b/test/Transforms/InstCombine/descale-zero.ll
new file mode 100644
index 00000000000..4347be48e61
--- /dev/null
+++ b/test/Transforms/InstCombine/descale-zero.ll
@@ -0,0 +1,20 @@
+; RUN: opt < %s -instcombine -S | FileCheck %s
+
+target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-apple-macosx10.10.0"
+
+define internal i8* @descale_zero() {
+entry:
+; CHECK: load i8*, i8** inttoptr (i64 48 to i8**), align 16
+; CHECK-NEXT: ret i8*
+  %i16_ptr = load i16*, i16** inttoptr (i64 48 to i16**), align 16
+  %num = load i64, i64* inttoptr (i64 64 to i64*), align 64
+  %num_times_2 = shl i64 %num, 1
+  %num_times_2_plus_4 = add i64 %num_times_2, 4
+  %i8_ptr = bitcast i16* %i16_ptr to i8*
+  %i8_ptr_num_times_2_plus_4 = getelementptr i8, i8* %i8_ptr, i64 %num_times_2_plus_4
+  %num_times_neg2 = mul i64 %num, -2
+  %num_times_neg2_minus_4 = add i64 %num_times_neg2, -4
+  %addr = getelementptr i8, i8* %i8_ptr_num_times_2_plus_4, i64 %num_times_neg2_minus_4
+  ret i8* %addr
+}
diff --git a/test/Transforms/InstCombine/gep-merge.ll b/test/Transforms/InstCombine/gep-merge.ll
deleted file mode 100644
index 3cfe781ac8b..00000000000
--- a/test/Transforms/InstCombine/gep-merge.ll
+++ /dev/null
@@ -1,48 +0,0 @@
-; This test makes sure that gep(gep ...) merge doesn't come into effect.
-; RUN: opt < %s -instcombine -S | FileCheck %s
-
-; Make sure there are no geps being merged.
-; CHECK-LABEL: @fn3(
-; CHECK: getelementptr
-; CHECK: getelementptr
-; CHECK: getelementptr
-
-@_ZN2cv1aE = global i8* zeroinitializer, align 8
-declare i32 @fn1() #2
-declare i32 @fn2() #2
-
-; Function Attrs: uwtable
-define linkonce_odr i32 @fn3() {
-entry:
-  %call = call i32 @fn1()
-  %call1 = call i32 @fn2()
-  %0 = load i8*, i8** @_ZN2cv1aE, align 8
-  %idx.ext2 = sext i32 %call1 to i64
-  %add.ptr3 = getelementptr inbounds i8, i8* %0, i64 %idx.ext2
-  br label %for.cond5
-
-for.cond5:
-  %total1 = phi i32 [ 0, %entry ], [ %total2, %for.body7 ]
-  %x.1 = phi i32 [ 0, %entry ], [ %inc, %for.body7 ]
-  %cmp6 = icmp slt i32 %x.1, %call
-  br i1 %cmp6, label %for.body7, label %for.cond34
-
-for.body7:                                        ; preds = %for.cond5
-  %mul = mul nsw i32 %x.1, 2
-  %idxprom = sext i32 %mul to i64
-  %arrayidx = getelementptr inbounds i8, i8* %add.ptr3, i64 %idxprom
-  %1 = load i8, i8* %arrayidx, align 1
-  %conv = zext i8 %1 to i32
-  %sub = sub nsw i32 %mul, 1
-  %idxprom10 = sext i32 %sub to i64
-  %arrayidx11 = getelementptr inbounds i8, i8* %add.ptr3, i64 %idxprom10
-  %2 = load i8, i8* %arrayidx11, align 1
-  %conv2 = zext i8 %2 to i32
-  %add1 = add nsw i32 %conv, %conv2
-  %total2 = add nsw i32 %total1, %add1
-  %inc = add nsw i32 %x.1, 1
-  br label %for.cond5
-
-for.cond34:
-  ret i32 %total1
-}
diff --git a/test/Transforms/InstCombine/getelementptr.ll b/test/Transforms/InstCombine/getelementptr.ll
index 276ada91f3c..9bb1b12a697 100644
--- a/test/Transforms/InstCombine/getelementptr.ll
+++ b/test/Transforms/InstCombine/getelementptr.ll
@@ -104,8 +104,8 @@ define i32* @test7(i32* %I, i64 %C, i64 %D) {
         %B = getelementptr i32, i32* %A, i64 %D
         ret i32* %B
 ; CHECK-LABEL: @test7(
-; CHECK: %A = getelementptr i32, i32* %I, i64 %C
-; CHECK: %B = getelementptr i32, i32* %A, i64 %D
+; CHECK: %A.sum = add i64 %C, %D
+; CHECK: getelementptr i32, i32* %I, i64 %A.sum
 }
 
 define i8* @test8([10 x i32]* %X) {
-- 
2.40.0