[PATCH] D94870: [InstSimplify] Handle commutativity for 'and' and 'outer or' for (~A & B) | ~(A | B) --> ~A

[Dávid Bolvanský via Phabricator via llvm-commits]

xbolva00 updated this revision to Diff 317187.
xbolva00 added a comment.

Simplify code.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D94870/new/

https://reviews.llvm.org/D94870

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


Index: llvm/test/Transforms/InstSimplify/or.ll
===================================================================
--- llvm/test/Transforms/InstSimplify/or.ll
+++ llvm/test/Transforms/InstSimplify/or.ll
@@ -399,11 +399,7 @@
 define i32 @and_or_not_or5(i32 %A, i32 %B) {
 ; CHECK-LABEL: @and_or_not_or5(
 ; CHECK-NEXT:    [[I:%.*]] = xor i32 [[A:%.*]], -1
-; CHECK-NEXT:    [[I2:%.*]] = and i32 [[B:%.*]], [[I]]
-; CHECK-NEXT:    [[I3:%.*]] = or i32 [[B]], [[A]]
-; CHECK-NEXT:    [[I4:%.*]] = xor i32 [[I3]], -1
-; CHECK-NEXT:    [[I5:%.*]] = or i32 [[I2]], [[I4]]
-; CHECK-NEXT:    ret i32 [[I5]]
+; CHECK-NEXT:    ret i32 [[I]]
 ;
   %i = xor i32 %A, -1
   %i2 = and i32 %B, %i
@@ -416,11 +412,7 @@
 define i32 @and_or_not_or6(i32 %A, i32 %B) {
 ; CHECK-LABEL: @and_or_not_or6(
 ; CHECK-NEXT:    [[I:%.*]] = xor i32 [[A:%.*]], -1
-; CHECK-NEXT:    [[I2:%.*]] = and i32 [[I]], [[B:%.*]]
-; CHECK-NEXT:    [[I3:%.*]] = or i32 [[B]], [[A]]
-; CHECK-NEXT:    [[I4:%.*]] = xor i32 [[I3]], -1
-; CHECK-NEXT:    [[I5:%.*]] = or i32 [[I4]], [[I2]]
-; CHECK-NEXT:    ret i32 [[I5]]
+; CHECK-NEXT:    ret i32 [[I]]
 ;
   %i = xor i32 %A, -1
   %i2 = and i32 %i, %B
@@ -433,11 +425,7 @@
 define i32 @and_or_not_or7(i32 %A, i32 %B) {
 ; CHECK-LABEL: @and_or_not_or7(
 ; CHECK-NEXT:    [[I:%.*]] = xor i32 [[A:%.*]], -1
-; CHECK-NEXT:    [[I2:%.*]] = and i32 [[B:%.*]], [[I]]
-; CHECK-NEXT:    [[I3:%.*]] = or i32 [[B]], [[A]]
-; CHECK-NEXT:    [[I4:%.*]] = xor i32 [[I3]], -1
-; CHECK-NEXT:    [[I5:%.*]] = or i32 [[I4]], [[I2]]
-; CHECK-NEXT:    ret i32 [[I5]]
+; CHECK-NEXT:    ret i32 [[I]]
 ;
   %i = xor i32 %A, -1
   %i2 = and i32 %B, %i
@@ -450,11 +438,7 @@
 define i32 @and_or_not_or8(i32 %A, i32 %B) {
 ; CHECK-LABEL: @and_or_not_or8(
 ; CHECK-NEXT:    [[I:%.*]] = xor i32 [[B:%.*]], -1
-; CHECK-NEXT:    [[I2:%.*]] = and i32 [[A:%.*]], [[I]]
-; CHECK-NEXT:    [[I3:%.*]] = or i32 [[B]], [[A]]
-; CHECK-NEXT:    [[I4:%.*]] = xor i32 [[I3]], -1
-; CHECK-NEXT:    [[I5:%.*]] = or i32 [[I4]], [[I2]]
-; CHECK-NEXT:    ret i32 [[I5]]
+; CHECK-NEXT:    ret i32 [[I]]
 ;
   %i = xor i32 %B, -1
   %i2 = and i32 %A, %i
Index: llvm/lib/Analysis/InstructionSimplify.cpp
===================================================================
--- llvm/lib/Analysis/InstructionSimplify.cpp
+++ llvm/lib/Analysis/InstructionSimplify.cpp
@@ -2224,7 +2224,7 @@
   if (Value *V = simplifyLogicOfAddSub(Op0, Op1, Instruction::Or))
     return V;
 
-  Value *A, *B;
+  Value *A, *B, *NotA;
   // (A & ~B) | (A ^ B) -> (A ^ B)
   // (~B & A) | (A ^ B) -> (A ^ B)
   // (A & ~B) | (B ^ A) -> (B ^ A)
@@ -2253,6 +2253,7 @@
        match(Op1, m_c_Xor(m_Not(m_Specific(A)), m_Specific(B)))))
     return Op1;
 
+  // Commute the 'or' operands.
   // (~A ^ B) | (A & B) -> (~A ^ B)
   // (~A ^ B) | (B & A) -> (~A ^ B)
   // (B ^ ~A) | (A & B) -> (B ^ ~A)
@@ -2266,9 +2267,18 @@
   // (~A & B) | ~(B | A) --> ~A
   // (B & ~A) | ~(A | B) --> ~A
   // (B & ~A) | ~(B | A) --> ~A
-  if (match(Op0, m_And(m_Not(m_Value(A)), m_Value(B))) &&
+  if (match(Op0, m_c_And(m_CombineAnd(m_Value(NotA), m_Not(m_Value(A))), m_Value(B))) &&
       match(Op1, m_Not(m_c_Or(m_Specific(A), m_Specific(B)))))
-    return cast<BinaryOperator>(Op0)->getOperand(0);
+    return NotA;
+
+  // Commute the 'or' operands.
+  // ~(A | B) | (~A & B) --> ~A
+  // ~(B | A) | (~A & B) --> ~A
+  // ~(A | B) | (B & ~A) --> ~A
+  // ~(B | A) | (B & ~A) --> ~A
+  if (match(Op1, m_c_And(m_CombineAnd(m_Value(NotA), m_Not(m_Value(A))), m_Value(B))) &&
+      match(Op0, m_Not(m_c_Or(m_Specific(A), m_Specific(B)))))
+    return NotA;
 
   if (Value *V = simplifyAndOrOfCmps(Q, Op0, Op1, false))
     return V;


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