diff options
| -rw-r--r-- | lib/Target/X86/X86ISelLowering.cpp | 17 | ||||
| -rw-r--r-- | test/CodeGen/X86/peep-test-0.ll (renamed from test/CodeGen/X86/peep-test.ll) | 0 | ||||
| -rw-r--r-- | test/CodeGen/X86/peep-test-1.ll | 23 |
3 files changed, 31 insertions, 9 deletions
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp index d56e672..33eee7a 100644 --- a/lib/Target/X86/X86ISelLowering.cpp +++ b/lib/Target/X86/X86ISelLowering.cpp @@ -5382,13 +5382,19 @@ SDValue X86TargetLowering::EmitTest(SDValue Op, SelectionDAG &DAG) { UE = Op.getNode()->use_end(); UI != UE; ++UI) if (UI->getOpcode() == ISD::STORE) goto default_case; - // An add of one will be selected as an INC. if (ConstantSDNode *C = - dyn_cast<ConstantSDNode>(Op.getNode()->getOperand(1))) + dyn_cast<ConstantSDNode>(Op.getNode()->getOperand(1))) { + // An add of one will be selected as an INC. if (C->getAPIntValue() == 1) { Opcode = X86ISD::INC; break; } + // An add of negative one (subtract of one) will be selected as a DEC. + if (C->getAPIntValue().isAllOnesValue()) { + Opcode = X86ISD::DEC; + break; + } + } // Otherwise use a regular EFLAGS-setting add. Opcode = X86ISD::ADD; break; @@ -5399,13 +5405,6 @@ SDValue X86TargetLowering::EmitTest(SDValue Op, SelectionDAG &DAG) { UE = Op.getNode()->use_end(); UI != UE; ++UI) if (UI->getOpcode() == ISD::STORE) goto default_case; - // A subtract of one will be selected as a DEC. - if (ConstantSDNode *C = - dyn_cast<ConstantSDNode>(Op.getNode()->getOperand(1))) - if (C->getAPIntValue() == 1) { - Opcode = X86ISD::DEC; - break; - } // Otherwise use a regular EFLAGS-setting sub. Opcode = X86ISD::SUB; break; diff --git a/test/CodeGen/X86/peep-test.ll b/test/CodeGen/X86/peep-test-0.ll index a95b564..a95b564 100644 --- a/test/CodeGen/X86/peep-test.ll +++ b/test/CodeGen/X86/peep-test-0.ll diff --git a/test/CodeGen/X86/peep-test-1.ll b/test/CodeGen/X86/peep-test-1.ll new file mode 100644 index 0000000..b4698e3 --- /dev/null +++ b/test/CodeGen/X86/peep-test-1.ll @@ -0,0 +1,23 @@ +; RUN: llvm-as < %s | llc -march=x86 > %t +; RUN: grep dec %t | count 1 +; RUN: not grep test %t +; RUN: not grep cmp %t + +define void @foo(i32 %n, double* nocapture %p) nounwind { + br label %bb + +bb: + %indvar = phi i32 [ 0, %0 ], [ %indvar.next, %bb ] + %i.03 = sub i32 %n, %indvar + %1 = getelementptr double* %p, i32 %i.03 + %2 = load double* %1, align 4 + %3 = mul double %2, 2.930000e+00 + store double %3, double* %1, align 4 + %4 = add i32 %i.03, -1 + %phitmp = icmp slt i32 %4, 0 + %indvar.next = add i32 %indvar, 1 + br i1 %phitmp, label %bb, label %return + +return: + ret void +} |