Add x86 isel lowering logic to form bit test with inverted condition. e.g.

x ^ -1.

Patch by David Majnemer.
rdar://12755626


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169339 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evan Cheng 2012-12-05 00:10:38 +00:00
parent 105ab4fe4b
commit 4e54480531
2 changed files with 114 additions and 9 deletions

View File

@ -8918,6 +8918,11 @@ SDValue X86TargetLowering::ConvertCmpIfNecessary(SDValue Cmp,
return DAG.getNode(X86ISD::SAHF, dl, MVT::i32, TruncSrl);
}
static bool isAllOnes(SDValue V) {
ConstantSDNode *C = dyn_cast<ConstantSDNode>(V);
return C && C->isAllOnesValue();
}
/// LowerToBT - Result of 'and' is compared against zero. Turn it into a BT node
/// if it's possible.
SDValue X86TargetLowering::LowerToBT(SDValue And, ISD::CondCode CC,
@ -8966,6 +8971,14 @@ SDValue X86TargetLowering::LowerToBT(SDValue And, ISD::CondCode CC,
}
if (LHS.getNode()) {
// If the LHS is of the form (x ^ -1) then replace the LHS with x and flip
// the condition code later.
bool Invert = false;
if (LHS.getOpcode() == ISD::XOR && isAllOnes(LHS.getOperand(1))) {
Invert = true;
LHS = LHS.getOperand(0);
}
// If LHS is i8, promote it to i32 with any_extend. There is no i8 BT
// instruction. Since the shift amount is in-range-or-undefined, we know
// that doing a bittest on the i32 value is ok. We extend to i32 because
@ -8981,7 +8994,10 @@ SDValue X86TargetLowering::LowerToBT(SDValue And, ISD::CondCode CC,
RHS = DAG.getNode(ISD::ANY_EXTEND, dl, LHS.getValueType(), RHS);
SDValue BT = DAG.getNode(X86ISD::BT, dl, MVT::i32, LHS, RHS);
unsigned Cond = CC == ISD::SETEQ ? X86::COND_AE : X86::COND_B;
X86::CondCode Cond = CC == ISD::SETEQ ? X86::COND_AE : X86::COND_B;
// Flip the condition if the LHS was a not instruction
if (Invert)
Cond = X86::GetOppositeBranchCondition(Cond);
return DAG.getNode(X86ISD::SETCC, dl, MVT::i8,
DAG.getConstant(Cond, MVT::i8), BT);
}
@ -9239,11 +9255,6 @@ static bool isZero(SDValue V) {
return C && C->isNullValue();
}
static bool isAllOnes(SDValue V) {
ConstantSDNode *C = dyn_cast<ConstantSDNode>(V);
return C && C->isAllOnesValue();
}
static bool isTruncWithZeroHighBitsInput(SDValue V, SelectionDAG &DAG) {
if (V.getOpcode() != ISD::TRUNCATE)
return false;

View File

@ -1,6 +1,4 @@
; RUN: llc < %s -march=x86 | grep btl | count 28
; RUN: llc < %s -march=x86 -mcpu=pentium4 | grep btl | not grep esp
; RUN: llc < %s -march=x86 -mcpu=penryn | grep btl | not grep esp
; RUN: llc < %s -mtriple=i386-apple-macosx -mcpu=penryn | FileCheck %s
; PR3253
; The register+memory form of the BT instruction should be usable on
@ -21,6 +19,9 @@
define void @test2(i32 %x, i32 %n) nounwind {
entry:
; CHECK: test2
; CHECK: btl %eax, %ecx
; CHECK: jb
%tmp29 = lshr i32 %x, %n ; <i32> [#uses=1]
%tmp3 = and i32 %tmp29, 1 ; <i32> [#uses=1]
%tmp4 = icmp eq i32 %tmp3, 0 ; <i1> [#uses=1]
@ -36,6 +37,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @test2b(i32 %x, i32 %n) nounwind {
entry:
; CHECK: test2b
; CHECK: btl %eax, %ecx
; CHECK: jb
%tmp29 = lshr i32 %x, %n ; <i32> [#uses=1]
%tmp3 = and i32 1, %tmp29
%tmp4 = icmp eq i32 %tmp3, 0 ; <i1> [#uses=1]
@ -51,6 +55,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @atest2(i32 %x, i32 %n) nounwind {
entry:
; CHECK: atest2
; CHECK: btl %eax, %ecx
; CHECK: jb
%tmp29 = ashr i32 %x, %n ; <i32> [#uses=1]
%tmp3 = and i32 %tmp29, 1 ; <i32> [#uses=1]
%tmp4 = icmp eq i32 %tmp3, 0 ; <i1> [#uses=1]
@ -66,6 +73,8 @@ UnifiedReturnBlock: ; preds = %entry
define void @atest2b(i32 %x, i32 %n) nounwind {
entry:
; CHECK: atest2b
; CHECK: btl %eax, %ecx
%tmp29 = ashr i32 %x, %n ; <i32> [#uses=1]
%tmp3 = and i32 1, %tmp29
%tmp4 = icmp eq i32 %tmp3, 0 ; <i1> [#uses=1]
@ -81,6 +90,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @test3(i32 %x, i32 %n) nounwind {
entry:
; CHECK: test3
; CHECK: btl %eax, %ecx
; CHECK: jb
%tmp29 = shl i32 1, %n ; <i32> [#uses=1]
%tmp3 = and i32 %tmp29, %x ; <i32> [#uses=1]
%tmp4 = icmp eq i32 %tmp3, 0 ; <i1> [#uses=1]
@ -96,6 +108,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @test3b(i32 %x, i32 %n) nounwind {
entry:
; CHECK: test3b
; CHECK: btl %eax, %ecx
; CHECK: jb
%tmp29 = shl i32 1, %n ; <i32> [#uses=1]
%tmp3 = and i32 %x, %tmp29
%tmp4 = icmp eq i32 %tmp3, 0 ; <i1> [#uses=1]
@ -111,6 +126,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @testne2(i32 %x, i32 %n) nounwind {
entry:
; CHECK: testne2
; CHECK: btl %eax, %ecx
; CHECK: jae
%tmp29 = lshr i32 %x, %n ; <i32> [#uses=1]
%tmp3 = and i32 %tmp29, 1 ; <i32> [#uses=1]
%tmp4 = icmp ne i32 %tmp3, 0 ; <i1> [#uses=1]
@ -126,6 +144,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @testne2b(i32 %x, i32 %n) nounwind {
entry:
; CHECK: testne2b
; CHECK: btl %eax, %ecx
; CHECK: jae
%tmp29 = lshr i32 %x, %n ; <i32> [#uses=1]
%tmp3 = and i32 1, %tmp29
%tmp4 = icmp ne i32 %tmp3, 0 ; <i1> [#uses=1]
@ -141,6 +162,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @atestne2(i32 %x, i32 %n) nounwind {
entry:
; CHECK: atestne2
; CHECK: btl %eax, %ecx
; CHECK: jae
%tmp29 = ashr i32 %x, %n ; <i32> [#uses=1]
%tmp3 = and i32 %tmp29, 1 ; <i32> [#uses=1]
%tmp4 = icmp ne i32 %tmp3, 0 ; <i1> [#uses=1]
@ -156,6 +180,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @atestne2b(i32 %x, i32 %n) nounwind {
entry:
; CHECK: atestne2b
; CHECK: btl %eax, %ecx
; CHECK: jae
%tmp29 = ashr i32 %x, %n ; <i32> [#uses=1]
%tmp3 = and i32 1, %tmp29
%tmp4 = icmp ne i32 %tmp3, 0 ; <i1> [#uses=1]
@ -171,6 +198,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @testne3(i32 %x, i32 %n) nounwind {
entry:
; CHECK: testne3
; CHECK: btl %eax, %ecx
; CHECK: jae
%tmp29 = shl i32 1, %n ; <i32> [#uses=1]
%tmp3 = and i32 %tmp29, %x ; <i32> [#uses=1]
%tmp4 = icmp ne i32 %tmp3, 0 ; <i1> [#uses=1]
@ -186,6 +216,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @testne3b(i32 %x, i32 %n) nounwind {
entry:
; CHECK: testne3b
; CHECK: btl %eax, %ecx
; CHECK: jae
%tmp29 = shl i32 1, %n ; <i32> [#uses=1]
%tmp3 = and i32 %x, %tmp29
%tmp4 = icmp ne i32 %tmp3, 0 ; <i1> [#uses=1]
@ -201,6 +234,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @query2(i32 %x, i32 %n) nounwind {
entry:
; CHECK: query2
; CHECK: btl %eax, %ecx
; CHECK: jae
%tmp29 = lshr i32 %x, %n ; <i32> [#uses=1]
%tmp3 = and i32 %tmp29, 1 ; <i32> [#uses=1]
%tmp4 = icmp eq i32 %tmp3, 1 ; <i1> [#uses=1]
@ -216,6 +252,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @query2b(i32 %x, i32 %n) nounwind {
entry:
; CHECK: query2b
; CHECK: btl %eax, %ecx
; CHECK: jae
%tmp29 = lshr i32 %x, %n ; <i32> [#uses=1]
%tmp3 = and i32 1, %tmp29
%tmp4 = icmp eq i32 %tmp3, 1 ; <i1> [#uses=1]
@ -231,6 +270,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @aquery2(i32 %x, i32 %n) nounwind {
entry:
; CHECK: aquery2
; CHECK: btl %eax, %ecx
; CHECK: jae
%tmp29 = ashr i32 %x, %n ; <i32> [#uses=1]
%tmp3 = and i32 %tmp29, 1 ; <i32> [#uses=1]
%tmp4 = icmp eq i32 %tmp3, 1 ; <i1> [#uses=1]
@ -246,6 +288,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @aquery2b(i32 %x, i32 %n) nounwind {
entry:
; CHECK: aquery2b
; CHECK: btl %eax, %ecx
; CHECK: jae
%tmp29 = ashr i32 %x, %n ; <i32> [#uses=1]
%tmp3 = and i32 1, %tmp29
%tmp4 = icmp eq i32 %tmp3, 1 ; <i1> [#uses=1]
@ -261,6 +306,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @query3(i32 %x, i32 %n) nounwind {
entry:
; CHECK: query3
; CHECK: btl %eax, %ecx
; CHECK: jae
%tmp29 = shl i32 1, %n ; <i32> [#uses=1]
%tmp3 = and i32 %tmp29, %x ; <i32> [#uses=1]
%tmp4 = icmp eq i32 %tmp3, %tmp29 ; <i1> [#uses=1]
@ -276,6 +324,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @query3b(i32 %x, i32 %n) nounwind {
entry:
; CHECK: query3b
; CHECK: btl %eax, %ecx
; CHECK: jae
%tmp29 = shl i32 1, %n ; <i32> [#uses=1]
%tmp3 = and i32 %x, %tmp29
%tmp4 = icmp eq i32 %tmp3, %tmp29 ; <i1> [#uses=1]
@ -291,6 +342,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @query3x(i32 %x, i32 %n) nounwind {
entry:
; CHECK: query3x
; CHECK: btl %eax, %ecx
; CHECK: jae
%tmp29 = shl i32 1, %n ; <i32> [#uses=1]
%tmp3 = and i32 %tmp29, %x ; <i32> [#uses=1]
%tmp4 = icmp eq i32 %tmp29, %tmp3 ; <i1> [#uses=1]
@ -306,6 +360,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @query3bx(i32 %x, i32 %n) nounwind {
entry:
; CHECK: query3bx
; CHECK: btl %eax, %ecx
; CHECK: jae
%tmp29 = shl i32 1, %n ; <i32> [#uses=1]
%tmp3 = and i32 %x, %tmp29
%tmp4 = icmp eq i32 %tmp29, %tmp3 ; <i1> [#uses=1]
@ -321,6 +378,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @queryne2(i32 %x, i32 %n) nounwind {
entry:
; CHECK: queryne2
; CHECK: btl %eax, %ecx
; CHECK: jb
%tmp29 = lshr i32 %x, %n ; <i32> [#uses=1]
%tmp3 = and i32 %tmp29, 1 ; <i32> [#uses=1]
%tmp4 = icmp ne i32 %tmp3, 1 ; <i1> [#uses=1]
@ -336,6 +396,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @queryne2b(i32 %x, i32 %n) nounwind {
entry:
; CHECK: queryne2b
; CHECK: btl %eax, %ecx
; CHECK: jb
%tmp29 = lshr i32 %x, %n ; <i32> [#uses=1]
%tmp3 = and i32 1, %tmp29
%tmp4 = icmp ne i32 %tmp3, 1 ; <i1> [#uses=1]
@ -351,6 +414,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @aqueryne2(i32 %x, i32 %n) nounwind {
entry:
; CHECK: aqueryne2
; CHECK: btl %eax, %ecx
; CHECK: jb
%tmp29 = ashr i32 %x, %n ; <i32> [#uses=1]
%tmp3 = and i32 %tmp29, 1 ; <i32> [#uses=1]
%tmp4 = icmp ne i32 %tmp3, 1 ; <i1> [#uses=1]
@ -366,6 +432,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @aqueryne2b(i32 %x, i32 %n) nounwind {
entry:
; CHECK: aqueryne2b
; CHECK: btl %eax, %ecx
; CHECK: jb
%tmp29 = ashr i32 %x, %n ; <i32> [#uses=1]
%tmp3 = and i32 1, %tmp29
%tmp4 = icmp ne i32 %tmp3, 1 ; <i1> [#uses=1]
@ -381,6 +450,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @queryne3(i32 %x, i32 %n) nounwind {
entry:
; CHECK: queryne3
; CHECK: btl %eax, %ecx
; CHECK: jb
%tmp29 = shl i32 1, %n ; <i32> [#uses=1]
%tmp3 = and i32 %tmp29, %x ; <i32> [#uses=1]
%tmp4 = icmp ne i32 %tmp3, %tmp29 ; <i1> [#uses=1]
@ -396,6 +468,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @queryne3b(i32 %x, i32 %n) nounwind {
entry:
; CHECK: queryne3b
; CHECK: btl %eax, %ecx
; CHECK: jb
%tmp29 = shl i32 1, %n ; <i32> [#uses=1]
%tmp3 = and i32 %x, %tmp29
%tmp4 = icmp ne i32 %tmp3, %tmp29 ; <i1> [#uses=1]
@ -411,6 +486,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @queryne3x(i32 %x, i32 %n) nounwind {
entry:
; CHECK: queryne3x
; CHECK: btl %eax, %ecx
; CHECK: jb
%tmp29 = shl i32 1, %n ; <i32> [#uses=1]
%tmp3 = and i32 %tmp29, %x ; <i32> [#uses=1]
%tmp4 = icmp ne i32 %tmp29, %tmp3 ; <i1> [#uses=1]
@ -426,6 +504,9 @@ UnifiedReturnBlock: ; preds = %entry
define void @queryne3bx(i32 %x, i32 %n) nounwind {
entry:
; CHECK: queryne3bx
; CHECK: btl %eax, %ecx
; CHECK: jb
%tmp29 = shl i32 1, %n ; <i32> [#uses=1]
%tmp3 = and i32 %x, %tmp29
%tmp4 = icmp ne i32 %tmp29, %tmp3 ; <i1> [#uses=1]
@ -440,3 +521,16 @@ UnifiedReturnBlock: ; preds = %entry
}
declare void @foo()
; rdar://12755626
define zeroext i1 @invert(i32 %flags, i32 %flag) nounwind {
; CHECK: invert
; CHECK: btl %eax, %ecx
; CHECK: setae
entry:
%neg = xor i32 %flags, -1
%shl = shl i32 1, %flag
%and = and i32 %shl, %neg
%tobool = icmp ne i32 %and, 0
ret i1 %tobool
}