large immediates. Add dag combine logic to recover in case the large
immediates doesn't fit in cmp immediate operand field.
int foo(unsigned long l) {
return (l>> 47) == 1;
}
we produce
%shr.mask = and i64 %l, -
140737488355328
%cmp = icmp eq i64 %shr.mask,
140737488355328
%conv = zext i1 %cmp to i32
ret i32 %conv
which codegens to
movq $0xffff800000000000,%rax
andq %rdi,%rax
movq $0x0000800000000000,%rcx
cmpq %rcx,%rax
sete %al
movzbl %al,%eax
ret
TargetLowering::SimplifySetCC would transform
(X & -256) == 256 -> (X >> 8) == 1
if the immediate fails the isLegalICmpImmediate() test. For x86,
that's immediates which are not a signed 32-bit immediate.
Based on a patch by Eli Friedman.
PR10328
rdar://
9758774
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160346
91177308-0d34-0410-b5e6-
96231b3b80d8
}
}
}
+
+ if (!isLegalICmpImmediate(C1.getSExtValue())) {
+ // (X & -256) == 256 -> (X >> 8) == 1
+ if ((Cond == ISD::SETEQ || Cond == ISD::SETNE) &&
+ N0.getOpcode() == ISD::AND && N0.hasOneUse()) {
+ if (ConstantSDNode *AndRHS =
+ dyn_cast<ConstantSDNode>(N0.getOperand(1))) {
+ const APInt &AndRHSC = AndRHS->getAPIntValue();
+ if ((-AndRHSC).isPowerOf2() && (AndRHSC & C1) == C1) {
+ unsigned ShiftBits = AndRHSC.countTrailingZeros();
+ EVT ShiftTy = DCI.isBeforeLegalize() ?
+ getPointerTy() : getShiftAmountTy(N0.getValueType());
+ EVT CmpTy = N0.getValueType();
+ SDValue Shift = DAG.getNode(ISD::SRL, dl, CmpTy, N0.getOperand(0),
+ DAG.getConstant(ShiftBits, ShiftTy));
+ SDValue CmpRHS = DAG.getConstant(C1.lshr(ShiftBits), CmpTy);
+ return DAG.getSetCC(dl, VT, Shift, CmpRHS, Cond);
+ }
+ }
+ }
+ }
}
if (isa<ConstantFPSDNode>(N0.getNode())) {
return true;
}
+bool X86TargetLowering::isLegalICmpImmediate(int64_t Imm) const {
+ return Imm == (int32_t)Imm;
+}
+
+bool X86TargetLowering::isLegalAddImmediate(int64_t Imm) const {
+ return Imm == (int32_t)Imm;
+}
+
bool X86TargetLowering::isTruncateFree(EVT VT1, EVT VT2) const {
if (!VT1.isInteger() || !VT2.isInteger())
return false;
/// by AM is legal for this target, for a load/store of the specified type.
virtual bool isLegalAddressingMode(const AddrMode &AM, Type *Ty)const;
+ /// isLegalICmpImmediate - Return true if the specified immediate is legal
+ /// icmp immediate, that is the target has icmp instructions which can
+ /// compare a register against the immediate without having to materialize
+ /// the immediate into a register.
+ virtual bool isLegalICmpImmediate(int64_t Imm) const;
+
+ /// isLegalAddImmediate - Return true if the specified immediate is legal
+ /// add immediate, that is the target has add instructions which can
+ /// add a register and the immediate without having to materialize
+ /// the immediate into a register.
+ virtual bool isLegalAddImmediate(int64_t Imm) const;
+
/// isTruncateFree - Return true if it's free to truncate a value of
/// type Ty1 to type Ty2. e.g. On x86 it's free to truncate a i32 value in
/// register EAX to i16 by referencing its sub-register AX.
}
; rdar://11866926
-define i32 @test7(i64 %res) nounwind uwtable readnone ssp {
+define i32 @test7(i64 %res) nounwind {
entry:
; CHECK: test7:
; CHECK-NOT: movabsq
ret i32 %lnot.ext
}
-define i32 @test8(i64 %res) nounwind uwtable readnone ssp {
+define i32 @test8(i64 %res) nounwind {
entry:
; CHECK: test8:
; CHECK-NOT: movabsq
ret i32 %lnot.ext
}
-define i32 @test9(i64 %res) nounwind uwtable readnone ssp {
+define i32 @test9(i64 %res) nounwind {
entry:
; CHECK: test9:
; CHECK-NOT: movabsq
ret i32 %lnot.ext
}
-define i32 @test10(i64 %res) nounwind uwtable readnone ssp {
+define i32 @test10(i64 %res) nounwind {
entry:
; CHECK: test10:
; CHECK-NOT: movabsq
ret i32 %lnot.ext
}
+; rdar://9758774
+define i32 @test11(i64 %l) nounwind {
+entry:
+; CHECK: test11:
+; CHECK-NOT: movabsq
+; CHECK-NOT: andq
+; CHECK: shrq $47, %rdi
+; CHECK: cmpq $1, %rdi
+ %shr.mask = and i64 %l, -140737488355328
+ %cmp = icmp eq i64 %shr.mask, 140737488355328
+ %conv = zext i1 %cmp to i32
+ ret i32 %conv
+}