Revert "[SCEV] add no wrap flag for SCEVAddExpr."

This reverts r366419 because the analysis performed is within the context of
the loop and it's only valid to add wrapping flags to "global" expressions if
they're always correct.

llvm-svn: 373184
(cherry picked from commit 58e8c79)

Author: TNorthover

llvm/lib/Analysis/ScalarEvolution.cpp

@@ -4991,7 +4991,7 @@ const SCEV *ScalarEvolution::createSimpleAffineAddRec(PHINode *PN,
   // overflow.
   if (auto *BEInst = dyn_cast<Instruction>(BEValueV))
     if (isLoopInvariant(Accum, L) && isAddRecNeverPoison(BEInst, L))
-      (void)getAddRecExpr(getAddExpr(StartVal, Accum, Flags), Accum, L, Flags);
+      (void)getAddRecExpr(getAddExpr(StartVal, Accum), Accum, L, Flags);
 
   return PHISCEV;
 }

llvm/test/Analysis/ScalarEvolution/limit-depth.ll

@@ -46,7 +46,7 @@ define void @test_mul(i32 %a, i32 %b, i32 %c, i32 %d, i32 %e, i32 %f) {
 define void @test_sext(i32 %a, i32 %b, i32 %c, i32 %d, i32 %e, i32 %f) {
 ; CHECK-LABEL: @test_sext
 ; CHECK:        %se2 = sext i64 %iv2.inc to i128
-; CHECK-NEXT:   -->  {(1 + (sext i64 {(sext i32 (1 + %a)<nsw> to i64),+,1}<nsw><%loop> to i128))<nsw>,+,1}<nsw><%loop2>
+; CHECK-NEXT:   -->  {(1 + (sext i64 {(sext i32 (1 + %a) to i64),+,1}<nsw><%loop> to i128))<nsw>,+,1}<nsw><%loop2>
 entry:
   br label %loop
 

llvm/test/Analysis/ScalarEvolution/nsw.ll

@@ -163,7 +163,7 @@ bb5:                                              ; preds = %bb2
 declare void @f(i32)
 
 ; CHECK-LABEL: nswnowrap
-; CHECK: --> {(1 + %v)<nsw>,+,1}<nsw><%for.body>{{ U: [^ ]+ S: [^ ]+}}{{ *}}Exits: (2 + %v)
+; CHECK: --> {(1 + %v)<nsw>,+,1}<nsw><%for.body>{{ U: [^ ]+ S: [^ ]+}}{{ *}}Exits: (1 + ((1 + %v)<nsw> smax %v))
 define void @nswnowrap(i32 %v, i32* %buf) {
 entry:
   %add = add nsw i32 %v, 1

llvm/test/Analysis/ScalarEvolution/trip-count12.ll

@@ -1,7 +1,7 @@
 ; RUN: opt < %s -analyze -scalar-evolution | FileCheck %s
 
 ; CHECK: Determining loop execution counts for: @test
-; CHECK: Loop %for.body: backedge-taken count is ((-2 + %len)<nsw> /u 2)
+; CHECK: Loop %for.body: backedge-taken count is ((-2 + %len) /u 2)
 ; CHECK: Loop %for.body: max backedge-taken count is 1073741823
 
 define zeroext i16 @test(i16* nocapture %p, i32 %len) nounwind readonly {

llvm/test/Analysis/ScalarEvolution/trip-count9.ll

@@ -179,7 +179,7 @@ exit:
 }
 
 ; CHECK: Determining loop execution counts for: @nsw_startx
-; CHECK: Loop %loop: backedge-taken count is (-1 + (-1 * %x) + ((1 + %x)<nsw> smax %n))
+; CHECK: Loop %loop: backedge-taken count is (-1 + (-1 * %x) + ((1 + %x) smax %n))
 ; CHECK: Loop %loop: max backedge-taken count is -1
 define void @nsw_startx(i4 %n, i4 %x) {
 entry:
@@ -195,7 +195,7 @@ exit:
 }
 
 ; CHECK: Determining loop execution counts for: @nsw_startx_step2
-; CHECK: Loop %loop: backedge-taken count is ((-1 + (-1 * %x) + ((2 + %x)<nsw> smax %n)) /u 2)
+; CHECK: Loop %loop: backedge-taken count is ((-1 + (-1 * %x) + ((2 + %x) smax %n)) /u 2)
 ; CHECK: Loop %loop: max backedge-taken count is 7
 define void @nsw_startx_step2(i4 %n, i4 %x) {
 entry:
@@ -381,7 +381,7 @@ exit:
 }
 
 ; CHECK: Determining loop execution counts for: @even_nsw_startx
-; CHECK: Loop %loop: backedge-taken count is (-1 + (-1 * %x) + ((1 + %x)<nsw> smax (2 * %n)))
+; CHECK: Loop %loop: backedge-taken count is (-1 + (-1 * %x) + ((1 + %x) smax (2 * %n)))
 ; CHECK: Loop %loop: max backedge-taken count is -2
 define void @even_nsw_startx(i4 %n, i4 %x) {
 entry:
@@ -398,7 +398,7 @@ exit:
 }
 
 ; CHECK: Determining loop execution counts for: @even_nsw_startx_step2
-; CHECK: Loop %loop: backedge-taken count is ((-1 + (-1 * %x) + ((2 + %x)<nsw> smax (2 * %n))) /u 2)
+; CHECK: Loop %loop: backedge-taken count is ((-1 + (-1 * %x) + ((2 + %x) smax (2 * %n))) /u 2)
 ; CHECK: Loop %loop: max backedge-taken count is 7
 define void @even_nsw_startx_step2(i4 %n, i4 %x) {
 entry: