RPCSX/llvm
1
0
Fork 0
mirror of https://github.com/RPCSX/llvm.git synced 2025-02-25 23:45:36 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

[InstCombine] Add one use checks to or/and->xnor folding

Browse Source 
If the components of the and/or had multiple uses, this transform created an additional instruction.

This patch makes sure we remove one of the components.

Differential Revision: https://reviews.llvm.org/D34498

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306027 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Craig Topper 2017-06-22 16:12:02 +00:00
parent 52e734792d
commit b776efaa09
2 changed files with 10 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
View File

@ -1230,9 +1230,10 @@ static Instruction *foldAndToXor(BinaryOperator &I,
// (A | ~B) & (B | ~A) --> ~(A ^ B)
// (~B | A) & (~A | B) --> ~(A ^ B)
// (~B | A) & (B | ~A) --> ~(A ^ B)
if (match(Op0, m_c_Or(m_Value(A), m_Not(m_Value(B)))) &&
match(Op1, m_c_Or(m_Not(m_Specific(A)), m_Specific(B))))
return BinaryOperator::CreateNot(Builder.CreateXor(A, B));
if (Op0->hasOneUse() || Op1->hasOneUse())
if (match(Op0, m_c_Or(m_Value(A), m_Not(m_Value(B)))) &&
match(Op1, m_c_Or(m_Not(m_Specific(A)), m_Specific(B))))
return BinaryOperator::CreateNot(Builder.CreateXor(A, B));
return nullptr;
}
@ -1247,9 +1248,10 @@ static Instruction *foldOrToXor(BinaryOperator &I,
// Operand complexity canonicalization guarantees that the 'and' is Op0.
// (A & B) | ~(A | B) --> ~(A ^ B)
// (A & B) | ~(B | A) --> ~(A ^ B)
if (match(Op0, m_And(m_Value(A), m_Value(B))) &&
match(Op1, m_Not(m_c_Or(m_Specific(A), m_Specific(B)))))
return BinaryOperator::CreateNot(Builder.CreateXor(A, B));
if (Op0->hasOneUse() || Op1->hasOneUse())
if (match(Op0, m_And(m_Value(A), m_Value(B))) &&
match(Op1, m_Not(m_c_Or(m_Specific(A), m_Specific(B)))))
return BinaryOperator::CreateNot(Builder.CreateXor(A, B));
// (A & ~B) | (~A & B) --> A ^ B
// (A & ~B) | (B & ~A) --> A ^ B

6
test/Transforms/InstCombine/and-or-not.ll
View File

@ -527,8 +527,7 @@ define i32 @and_to_nxor_multiuse(float %fa, float %fb) {
; CHECK-NEXT: [[NOTB:%.*]] = xor i32 [[B]], -1
; CHECK-NEXT: [[OR1:%.*]] = or i32 [[NOTA]], [[B]]
; CHECK-NEXT: [[OR2:%.*]] = or i32 [[NOTB]], [[A]]
; CHECK-NEXT: [[TMP1:%.*]] = xor i32 [[B]], [[A]]
; CHECK-NEXT: [[AND:%.*]] = xor i32 [[TMP1]], -1
; CHECK-NEXT: [[AND:%.*]] = and i32 [[OR1]], [[OR2]]
; CHECK-NEXT: [[MUL1:%.*]] = mul i32 [[OR1]], [[OR2]]
; CHECK-NEXT: [[MUL2:%.*]] = mul i32 [[MUL1]], [[AND]]
; CHECK-NEXT: ret i32 [[MUL2]]
@ -552,8 +551,7 @@ define i32 @or_to_nxor_multiuse(i32 %a, i32 %b) {
; CHECK-NEXT: [[AND:%.*]] = and i32 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT: [[OR:%.*]] = or i32 [[A]], [[B]]
; CHECK-NEXT: [[NOTOR:%.*]] = xor i32 [[OR]], -1
; CHECK-NEXT: [[TMP1:%.*]] = xor i32 [[A]], [[B]]
; CHECK-NEXT: [[OR2:%.*]] = xor i32 [[TMP1]], -1
; CHECK-NEXT: [[OR2:%.*]] = or i32 [[AND]], [[NOTOR]]
; CHECK-NEXT: [[MUL1:%.*]] = mul i32 [[AND]], [[NOTOR]]
; CHECK-NEXT: [[MUL2:%.*]] = mul i32 [[MUL1]], [[OR2]]
; CHECK-NEXT: ret i32 [[MUL2]]