6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-08-22 10:29:35 +00:00
Code Issues Projects Releases Wiki Activity

Optimize pointer comparison into the typesafe form, now that the backends will

Browse Source 
handle them efficiently. This is the opposite direction of the transformation
we used to have here.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92418 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Nick Lewycky 2010-01-02 15:25:44 +00:00
parent bef37376be
commit 546d63176e
2 changed files with 33 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
lib/Transforms/Scalar/InstructionCombining.cpp
View File

@ -4432,8 +4432,7 @@ Instruction *InstCombiner::visitAnd(BinaryOperator &I) {
// See if we can simplify any instructions used by the instruction whose sole
// purpose is to compute bits we don't care about.
if (SimplifyDemandedInstructionBits(I))
return &I;
return &I;
if (ConstantInt *AndRHS = dyn_cast<ConstantInt>(Op1)) {
const APInt &AndRHSMask = AndRHS->getValue();
@ -7312,6 +7311,25 @@ Instruction *InstCombiner::visitICmpInstWithInstAndIntCst(ICmpInst &ICI,
}
}
break;
case Instruction::Or: {
if (!ICI.isEquality() || !RHS->isNullValue() || !LHSI->hasOneUse())
break;
Value *P, *Q;
if (match(LHSI, m_Or(m_PtrToInt(m_Value(P)), m_PtrToInt(m_Value(Q))))) {
// Simplify icmp eq (or (ptrtoint P), (ptrtoint Q)), 0
// -> and (icmp eq P, null), (icmp eq Q, null).
Value *ICIP = Builder->CreateICmp(ICI.getPredicate(), P,
Constant::getNullValue(P->getType()));
Value *ICIQ = Builder->CreateICmp(ICI.getPredicate(), Q,
Constant::getNullValue(Q->getType()));
Instruction *And = BinaryOperator::CreateAnd(ICIP, ICIQ, "");
And->takeName(&ICI);
return And;
}
break;
}
case Instruction::Shl: { // (icmp pred (shl X, ShAmt), CI)
ConstantInt *ShAmt = dyn_cast<ConstantInt>(LHSI->getOperand(1));

13
test/Transforms/InstCombine/or.ll
View File

@ -268,6 +268,19 @@ define i1 @test26(i32 %A, i32 %B) {
; CHECK: ret i1
}
define i1 @test27(i32* %A, i32* %B) {
%C1 = ptrtoint i32* %A to i32
%C2 = ptrtoint i32* %B to i32
%D = or i32 %C1, %C2
%E = icmp eq i32 %D, 0
ret i1 %E
; CHECK: @test27
; CHECK: icmp eq i32* %A, null
; CHECK: icmp eq i32* %B, null
; CHECK: and i1
; CHECK: ret i1
}
; PR5634
define i1 @test28(i32 %A, i32 %B) {
%C1 = icmp ne i32 %A, 0