Revert the addition of hasNoPointerOverflow to GEPOperator.

Getelementptrs that are defined to wrap are virtually useless to
optimization, and getelementptrs that are undefined on any kind
of overflow are too restrictive -- it's difficult to ensure that
all intermediate addresses are within bounds. I'm going to take
a different approach.

Remove a few optimizations that depended on this flag.

llvm-svn: 76437

5 files changed, 35 insertions, 132 deletions

diff --git a/llvm/test/CodeGen/X86/iv-users-in-other-loops.ll b/llvm/test/CodeGen/X86/iv-users-in-other-loops.ll
index a48f0616291..af1434ad1ae 100644
--- a/llvm/test/CodeGen/X86/iv-users-in-other-loops.ll
+++ b/llvm/test/CodeGen/X86/iv-users-in-other-loops.ll
@@ -3,8 +3,8 @@
 ; RUN: grep dec %t | count 2
 ; RUN: grep addq %t | count 13
 ; RUN: not grep addb %t
-; RUN: grep leaq %t | count 8
-; RUN: grep leal %t | count 4
+; RUN: grep leaq %t | count 9
+; RUN: grep leal %t | count 3
 ; RUN: grep movq %t | count 5
 
 ; IV users in each of the loops from other loops shouldn't cause LSR
diff --git a/llvm/test/Transforms/IndVarSimplify/max-pointer.ll b/llvm/test/Transforms/IndVarSimplify/max-pointer.ll
index ba2b2fa8348..2ee08dbc38b 100644
--- a/llvm/test/Transforms/IndVarSimplify/max-pointer.ll
+++ b/llvm/test/Transforms/IndVarSimplify/max-pointer.ll
@@ -22,58 +22,6 @@ return:		; preds = %bb2
 	ret void
 }
 
-define void @bar(i8* %str1Ptr, i64 %s, i8* %inLastBytePtr) nounwind {
-entry:
-        %str2Ptr = inttoptr i64 %s to i8*
-	%0 = icmp ult i8* %str2Ptr, %str1Ptr		; <i1> [#uses=1]
-	%str2Ptr_addr.0 = select i1 %0, i8* %str1Ptr, i8* %str2Ptr		; <i8*> [#uses=1]
-	br label %bb2
-
-bb2:		; preds = %bb2, %entry
-	%str2Ptr_addr.1 = phi i8* [ %str2Ptr_addr.0, %entry ], [ %1, %bb2 ]		; <i8*> [#uses=1]
-	%1 = getelementptr i8* %str2Ptr_addr.1, i64 1		; <i8*> [#uses=2]
-	%2 = icmp ult i8* %1, %inLastBytePtr		; <i1> [#uses=0]
-	br i1 false, label %bb2, label %return
-
-return:		; preds = %bb2
-	ret void
-}
-
-define void @qux(i64 %t, i64 %s, i8* %inLastBytePtr) nounwind {
-entry:
-        %str1Ptr = inttoptr i64 %t to i8*
-        %str2Ptr = inttoptr i64 %s to i8*
-	%0 = icmp ult i8* %str2Ptr, %str1Ptr		; <i1> [#uses=1]
-	%str2Ptr_addr.0 = select i1 %0, i8* %str1Ptr, i8* %str2Ptr		; <i8*> [#uses=1]
-	br label %bb2
-
-bb2:		; preds = %bb2, %entry
-	%str2Ptr_addr.1 = phi i8* [ %str2Ptr_addr.0, %entry ], [ %1, %bb2 ]		; <i8*> [#uses=1]
-	%1 = getelementptr i8* %str2Ptr_addr.1, i64 1		; <i8*> [#uses=2]
-	%2 = icmp ult i8* %1, %inLastBytePtr		; <i1> [#uses=0]
-	br i1 false, label %bb2, label %return
-
-return:		; preds = %bb2
-	ret void
-}
-
-define void @vor(i64 %t, i8* %str2Ptr, i8* %inLastBytePtr) nounwind {
-entry:
-        %str1Ptr = inttoptr i64 %t to i8*
-	%0 = icmp ult i8* %str2Ptr, %str1Ptr		; <i1> [#uses=1]
-	%str2Ptr_addr.0 = select i1 %0, i8* %str1Ptr, i8* %str2Ptr		; <i8*> [#uses=1]
-	br label %bb2
-
-bb2:		; preds = %bb2, %entry
-	%str2Ptr_addr.1 = phi i8* [ %str2Ptr_addr.0, %entry ], [ %1, %bb2 ]		; <i8*> [#uses=1]
-	%1 = getelementptr i8* %str2Ptr_addr.1, i64 1		; <i8*> [#uses=2]
-	%2 = icmp ult i8* %1, %inLastBytePtr		; <i1> [#uses=0]
-	br i1 false, label %bb2, label %return
-
-return:		; preds = %bb2
-	ret void
-}
-
 define void @sfoo(i8* %str1Ptr, i8* %str2Ptr, i8* %inLastBytePtr) nounwind {
 entry:
 	%0 = icmp slt i8* %str2Ptr, %str1Ptr		; <i1> [#uses=1]
@@ -89,57 +37,3 @@ bb2:		; preds = %bb2, %entry
 return:		; preds = %bb2
 	ret void
 }
-
-define void @sbar(i8* %str1Ptr, i64 %s, i8* %inLastBytePtr) nounwind {
-entry:
-        %str2Ptr = inttoptr i64 %s to i8*
-	%0 = icmp slt i8* %str2Ptr, %str1Ptr		; <i1> [#uses=1]
-	%str2Ptr_addr.0 = select i1 %0, i8* %str1Ptr, i8* %str2Ptr		; <i8*> [#uses=1]
-	br label %bb2
-
-bb2:		; preds = %bb2, %entry
-	%str2Ptr_addr.1 = phi i8* [ %str2Ptr_addr.0, %entry ], [ %1, %bb2 ]		; <i8*> [#uses=1]
-	%1 = getelementptr i8* %str2Ptr_addr.1, i64 1		; <i8*> [#uses=2]
-	%2 = icmp slt i8* %1, %inLastBytePtr		; <i1> [#uses=0]
-	br i1 false, label %bb2, label %return
-
-return:		; preds = %bb2
-	ret void
-}
-
-define void @squx(i64 %t, i64 %s, i8* %inLastBytePtr) nounwind {
-entry:
-        %str1Ptr = inttoptr i64 %t to i8*
-        %str2Ptr = inttoptr i64 %s to i8*
-	%0 = icmp slt i8* %str2Ptr, %str1Ptr		; <i1> [#uses=1]
-	%str2Ptr_addr.0 = select i1 %0, i8* %str1Ptr, i8* %str2Ptr		; <i8*> [#uses=1]
-	br label %bb2
-
-bb2:		; preds = %bb2, %entry
-	%str2Ptr_addr.1 = phi i8* [ %str2Ptr_addr.0, %entry ], [ %1, %bb2 ]		; <i8*> [#uses=1]
-	%1 = getelementptr i8* %str2Ptr_addr.1, i64 1		; <i8*> [#uses=2]
-	%2 = icmp slt i8* %1, %inLastBytePtr		; <i1> [#uses=0]
-	br i1 false, label %bb2, label %return
-
-return:		; preds = %bb2
-	ret void
-}
-
-define void @svor(i64 %t, i8* %str2Ptr, i8* %inLastBytePtr) nounwind {
-entry:
-        %str1Ptr = inttoptr i64 %t to i8*
-	%0 = icmp slt i8* %str2Ptr, %str1Ptr		; <i1> [#uses=1]
-	%str2Ptr_addr.0 = select i1 %0, i8* %str1Ptr, i8* %str2Ptr		; <i8*> [#uses=1]
-	br label %bb2
-
-bb2:		; preds = %bb2, %entry
-	%str2Ptr_addr.1 = phi i8* [ %str2Ptr_addr.0, %entry ], [ %1, %bb2 ]		; <i8*> [#uses=1]
-	%1 = getelementptr i8* %str2Ptr_addr.1, i64 1		; <i8*> [#uses=2]
-	%2 = icmp slt i8* %1, %inLastBytePtr		; <i1> [#uses=0]
-	br i1 false, label %bb2, label %return
-
-return:		; preds = %bb2
-	ret void
-}
-
-
diff --git a/llvm/test/Transforms/InstCombine/add2.ll b/llvm/test/Transforms/InstCombine/add2.ll
index 161d56b40b5..cd67d96a01a 100644
--- a/llvm/test/Transforms/InstCombine/add2.ll
+++ b/llvm/test/Transforms/InstCombine/add2.ll
@@ -1,9 +1,4 @@
-; RUN: llvm-as < %s | opt -instcombine | llvm-dis | \
-; RUN:    grep -v OK | not grep add
-
-;; Target triple for gep raising case below.
-target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
-target triple = "i686-apple-darwin8"
+; RUN: llvm-as < %s | opt -instcombine | llvm-dis | not grep add
 
 define i64 @test1(i64 %A, i32 %B) {
         %tmp12 = zext i32 %B to i64
@@ -13,23 +8,6 @@ define i64 @test1(i64 %A, i32 %B) {
         ret i64 %tmp6
 }
 
-; PR1795
-define void @test2(i32 %.val24) {
-EntryBlock:
-        add i32 %.val24, -12
-        inttoptr i32 %0 to i32*
-        store i32 1, i32* %1
-        add i32 %.val24, -16
-        inttoptr i32 %2 to i32*
-        getelementptr i32* %3, i32 1
-        load i32* %4
-        tail call i32 @callee( i32 %5 )
-        ret void
-}
-
-declare i32 @callee(i32)
-
-
 define i32 @test3(i32 %A) {
   %B = and i32 %A, 7
   %C = and i32 %A, 32
diff --git a/llvm/test/Transforms/InstCombine/add3.ll b/llvm/test/Transforms/InstCombine/add3.ll
new file mode 100644
index 00000000000..55e7ec7a1db
--- /dev/null
+++ b/llvm/test/Transforms/InstCombine/add3.ll
@@ -0,0 +1,21 @@
+; RUN: llvm-as < %s | opt -instcombine | llvm-dis | grep inttoptr | count 2
+
+;; Target triple for gep raising case below.
+target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
+target triple = "i686-apple-darwin8"
+
+; PR1795
+define void @test2(i32 %.val24) {
+EntryBlock:
+        add i32 %.val24, -12
+        inttoptr i32 %0 to i32*
+        store i32 1, i32* %1
+        add i32 %.val24, -16
+        inttoptr i32 %2 to i32*
+        getelementptr i32* %3, i32 1
+        load i32* %4
+        tail call i32 @callee( i32 %5 )
+        ret void
+}
+
+declare i32 @callee(i32)
diff --git a/llvm/test/Transforms/InstCombine/cast_ptr.ll b/llvm/test/Transforms/InstCombine/cast_ptr.ll
index fd600a88304..9b87ed094ea 100644
--- a/llvm/test/Transforms/InstCombine/cast_ptr.ll
+++ b/llvm/test/Transforms/InstCombine/cast_ptr.ll
@@ -1,8 +1,15 @@
 ; Tests to make sure elimination of casts is working correctly
-; RUN: llvm-as < %s | opt -instcombine | llvm-dis | notcast
+; RUN: llvm-as < %s | opt -instcombine | llvm-dis | FileCheck %s
 
 target datalayout = "p:32:32"
 
+; This shouldn't convert to getelementptr because the relationship
+; between the arithmetic and the layout of allocated memory is
+; entirely unknown.
+; CHECK: @test1
+; CHECK: ptrtoint
+; CHECK: add
+; CHECK: inttoptr
 define i8* @test1(i8* %t) {
         %tmpc = ptrtoint i8* %t to i32          ; <i32> [#uses=1]
         %tmpa = add i32 %tmpc, 32               ; <i32> [#uses=1]
@@ -10,6 +17,9 @@ define i8* @test1(i8* %t) {
         ret i8* %tv
 }
 
+; These casts should be folded away.
+; CHECK: @test2
+; CHECK: icmp eq i8* %a, %b
 define i1 @test2(i8* %a, i8* %b) {
         %tmpa = ptrtoint i8* %a to i32          ; <i32> [#uses=1]
         %tmpb = ptrtoint i8* %b to i32          ; <i32> [#uses=1]