[llvm] 833cdb0 - Revert "[InstSimplify] Fold A|B | (A^B) --> A|B"

[Stanislav Mekhanoshin via llvm-commits]

Author: Stanislav Mekhanoshin
Date: 2021-11-15T14:56:20-08:00
New Revision: 833cdb0a079d26c39fe2a76c353427afbac84917

URL: https://github.com/llvm/llvm-project/commit/833cdb0a079d26c39fe2a76c353427afbac84917
DIFF: https://github.com/llvm/llvm-project/commit/833cdb0a079d26c39fe2a76c353427afbac84917.diff

LOG: Revert "[InstSimplify] Fold A|B | (A^B) --> A|B"

This reverts commit 193c40e9667ca2b173232b393fc72ea9e4944aa3.

Added: 
    

Modified: 
    llvm/lib/Analysis/InstructionSimplify.cpp
    llvm/test/Transforms/InstSimplify/or.ll

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Analysis/InstructionSimplify.cpp b/llvm/lib/Analysis/InstructionSimplify.cpp
index 864eeea4f8bfd..d40658398f1b0 100644
--- a/llvm/lib/Analysis/InstructionSimplify.cpp
+++ b/llvm/lib/Analysis/InstructionSimplify.cpp
@@ -2265,19 +2265,6 @@ static Value *SimplifyOrInst(Value *Op0, Value *Op1, const SimplifyQuery &Q,
        match(Op0, m_c_Xor(m_Not(m_Specific(A)), m_Specific(B)))))
     return Op0;
 
-  // (A | B) | (A ^ B) --> A | B
-  // (B | A) | (A ^ B) --> B | A
-  if (match(Op1, m_Xor(m_Value(A), m_Value(B))) &&
-      match(Op0, m_c_Or(m_Specific(A), m_Specific(B))))
-    return Op0;
-
-  // Commute the outer 'or' operands.
-  // (A ^ B) | (A | B) --> A | B
-  // (A ^ B) | (B | A) --> B | A
-  if (match(Op0, m_Xor(m_Value(A), m_Value(B))) &&
-      match(Op1, m_c_Or(m_Specific(A), m_Specific(B))))
-    return Op1;
-
   // (~A & B) | ~(A | B) --> ~A
   // (~A & B) | ~(B | A) --> ~A
   // (B & ~A) | ~(A | B) --> ~A

diff  --git a/llvm/test/Transforms/InstSimplify/or.ll b/llvm/test/Transforms/InstSimplify/or.ll
index d11aedf149d95..038112a11efd3 100644
--- a/llvm/test/Transforms/InstSimplify/or.ll
+++ b/llvm/test/Transforms/InstSimplify/or.ll
@@ -451,7 +451,9 @@ define i32 @and_or_not_or8(i32 %A, i32 %B) {
 define i69 @or_or_xor(i69 %A, i69 %B) {
 ; CHECK-LABEL: @or_or_xor(
 ; CHECK-NEXT:    [[I1:%.*]] = or i69 [[A:%.*]], [[B:%.*]]
-; CHECK-NEXT:    ret i69 [[I1]]
+; CHECK-NEXT:    [[I2:%.*]] = xor i69 [[A]], [[B]]
+; CHECK-NEXT:    [[I3:%.*]] = or i69 [[I1]], [[I2]]
+; CHECK-NEXT:    ret i69 [[I3]]
 ;
   %i1 = or i69 %A, %B
   %i2 = xor i69 %A, %B
@@ -459,25 +461,12 @@ define i69 @or_or_xor(i69 %A, i69 %B) {
   ret i69 %i3
 }
 
-; (B | A) | (A ^ B) --> B | A
-
-define i8 @or_or_xor_inner_or_commuted(i8 %A, i8 %B) {
-; CHECK-LABEL: @or_or_xor_inner_or_commuted(
-; CHECK-NEXT:    [[I1:%.*]] = or i8 [[B:%.*]], [[A:%.*]]
-; CHECK-NEXT:    ret i8 [[I1]]
-;
-  %i1 = or i8 %B, %A
-  %i2 = xor i8 %A, %B
-  %i3 = or i8 %i1, %i2
-  ret i8 %i3
-}
-
-; (A ^ B) | (A | B) --> A | B
-
 define <4 x i4> @or_or_xor_commuted(<4 x i4> %A, <4 x i4> %B) {
 ; CHECK-LABEL: @or_or_xor_commuted(
 ; CHECK-NEXT:    [[I1:%.*]] = or <4 x i4> [[A:%.*]], [[B:%.*]]
-; CHECK-NEXT:    ret <4 x i4> [[I1]]
+; CHECK-NEXT:    [[I2:%.*]] = xor <4 x i4> [[A]], [[B]]
+; CHECK-NEXT:    [[I3:%.*]] = or <4 x i4> [[I2]], [[I1]]
+; CHECK-NEXT:    ret <4 x i4> [[I3]]
 ;
   %i1 = or <4 x i4> %A, %B
   %i2 = xor <4 x i4> %A, %B
@@ -485,19 +474,6 @@ define <4 x i4> @or_or_xor_commuted(<4 x i4> %A, <4 x i4> %B) {
   ret <4 x i4> %i3
 }
 
-; (A ^ B) | (B | A) --> B | A
-
-define i4 @or_or_xor_inner_or_outer_or_commuted(i4 %A, i4 %B) {
-; CHECK-LABEL: @or_or_xor_inner_or_outer_or_commuted(
-; CHECK-NEXT:    [[I1:%.*]] = or i4 [[B:%.*]], [[A:%.*]]
-; CHECK-NEXT:    ret i4 [[I1]]
-;
-  %i1 = or i4 %B, %A
-  %i2 = xor i4 %A, %B
-  %i3 = or i4 %i2, %i1
-  ret i4 %i3
-}
-
 define i32 @shifted_all_ones(i32 %shamt) {
 ; CHECK-LABEL: @shifted_all_ones(
 ; CHECK-NEXT:    ret i32 -1