From 42cd8cd8626a7f5eb14b0b43b866dd90bd33277b Mon Sep 17 00:00:00 2001 From: Craig Topper Date: Mon, 1 Oct 2018 21:35:28 +0000 Subject: [PATCH] Recommit r343499 "[X86] Enable load folding in the test shrinking code" Original message: This patch adds load folding support to the test shrinking code. This was noticed missing in the review for D52669 llvm-svn: 343540 --- llvm/lib/Target/X86/X86ISelDAGToDAG.cpp | 34 ++++++++++++++++++------- llvm/test/CodeGen/X86/test-shrink.ll | 12 +++------ 2 files changed, 29 insertions(+), 17 deletions(-) diff --git a/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp b/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp index d9c92ecf6c30..be079659da4e 100644 --- a/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp +++ b/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp @@ -3412,7 +3412,7 @@ void X86DAGToDAGISel::Select(SDNode *Node) { MVT VT; int SubRegOp; - unsigned Op; + unsigned ROpc, MOpc; // For each of these checks we need to be careful if the sign flag is // being used. It is only safe to use the sign flag in two conditions, @@ -3425,7 +3425,8 @@ void X86DAGToDAGISel::Select(SDNode *Node) { // For example, convert "testl %eax, $8" to "testb %al, $8" VT = MVT::i8; SubRegOp = X86::sub_8bit; - Op = X86::TEST8ri; + ROpc = X86::TEST8ri; + MOpc = X86::TEST8mi; } else if (OptForMinSize && isUInt<16>(Mask) && (!(Mask & 0x8000) || CmpVT == MVT::i16 || hasNoSignedComparisonUses(Node))) { @@ -3435,7 +3436,8 @@ void X86DAGToDAGISel::Select(SDNode *Node) { // changing prefix penalty in the decoders. VT = MVT::i16; SubRegOp = X86::sub_16bit; - Op = X86::TEST16ri; + ROpc = X86::TEST16ri; + MOpc = X86::TEST16mi; } else if (isUInt<32>(Mask) && N0.getValueType() != MVT::i16 && ((!(Mask & 0x80000000) && // Without minsize 16-bit Cmps can get here so we need to @@ -3449,7 +3451,8 @@ void X86DAGToDAGISel::Select(SDNode *Node) { // they had a good reason not to and do not promote here. VT = MVT::i32; SubRegOp = X86::sub_32bit; - Op = X86::TEST32ri; + ROpc = X86::TEST32ri; + MOpc = X86::TEST32mi; } else { // No eligible transformation was found. break; @@ -3460,12 +3463,25 @@ void X86DAGToDAGISel::Select(SDNode *Node) { SDValue Imm = CurDAG->getTargetConstant(Mask, dl, VT); SDValue Reg = N0.getOperand(0); - // Extract the subregister if necessary. - if (N0.getValueType() != VT) - Reg = CurDAG->getTargetExtractSubreg(SubRegOp, dl, VT, Reg); - // Emit a testl or testw. - SDNode *NewNode = CurDAG->getMachineNode(Op, dl, MVT::i32, Reg, Imm); + MachineSDNode *NewNode; + SDValue Tmp0, Tmp1, Tmp2, Tmp3, Tmp4; + if (tryFoldLoad(Node, N0.getNode(), Reg, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4)) { + SDValue Ops[] = { Tmp0, Tmp1, Tmp2, Tmp3, Tmp4, Imm, + Reg.getOperand(0) }; + NewNode = CurDAG->getMachineNode(MOpc, dl, MVT::i32, MVT::Other, Ops); + // Update the chain. + ReplaceUses(Reg.getValue(1), SDValue(NewNode, 1)); + // Record the mem-refs + CurDAG->setNodeMemRefs(NewNode, + {cast(Reg)->getMemOperand()}); + } else { + // Extract the subregister if necessary. + if (N0.getValueType() != VT) + Reg = CurDAG->getTargetExtractSubreg(SubRegOp, dl, VT, Reg); + + NewNode = CurDAG->getMachineNode(ROpc, dl, MVT::i32, Reg, Imm); + } // Replace CMP with TEST. ReplaceNode(Node, NewNode); return; diff --git a/llvm/test/CodeGen/X86/test-shrink.ll b/llvm/test/CodeGen/X86/test-shrink.ll index ea68d38dcf1c..5e9f49571dd8 100644 --- a/llvm/test/CodeGen/X86/test-shrink.ll +++ b/llvm/test/CodeGen/X86/test-shrink.ll @@ -645,8 +645,7 @@ define void @and32_trunc_8_sign(i32 %x) nounwind { ; ; CHECK-X86-LABEL: and32_trunc_8_sign: ; CHECK-X86: # %bb.0: -; CHECK-X86-NEXT: movl {{[0-9]+}}(%esp), %eax -; CHECK-X86-NEXT: testb $-128, %al +; CHECK-X86-NEXT: testb $-128, {{[0-9]+}}(%esp) ; CHECK-X86-NEXT: jg .LBB14_2 ; CHECK-X86-NEXT: # %bb.1: # %yes ; CHECK-X86-NEXT: calll bar @@ -689,8 +688,7 @@ define void @and64_trunc_8_sign(i64 %x) nounwind { ; ; CHECK-X86-LABEL: and64_trunc_8_sign: ; CHECK-X86: # %bb.0: -; CHECK-X86-NEXT: movl {{[0-9]+}}(%esp), %eax -; CHECK-X86-NEXT: testb $-128, %al +; CHECK-X86-NEXT: testb $-128, {{[0-9]+}}(%esp) ; CHECK-X86-NEXT: jg .LBB15_2 ; CHECK-X86-NEXT: # %bb.1: # %yes ; CHECK-X86-NEXT: calll bar @@ -780,8 +778,7 @@ define void @and32_trunc_16_sign_minsize(i32 %x) minsize nounwind { ; ; CHECK-X86-LABEL: and32_trunc_16_sign_minsize: ; CHECK-X86: # %bb.0: -; CHECK-X86-NEXT: movl {{[0-9]+}}(%esp), %eax -; CHECK-X86-NEXT: testw $-32768, %ax # imm = 0x8000 +; CHECK-X86-NEXT: testw $-32768, {{[0-9]+}}(%esp) # imm = 0x8000 ; CHECK-X86-NEXT: jg .LBB17_2 ; CHECK-X86-NEXT: # %bb.1: # %yes ; CHECK-X86-NEXT: calll bar @@ -871,8 +868,7 @@ define void @and64_trunc_16_sign_minsize(i64 %x) minsize nounwind { ; ; CHECK-X86-LABEL: and64_trunc_16_sign_minsize: ; CHECK-X86: # %bb.0: -; CHECK-X86-NEXT: movl {{[0-9]+}}(%esp), %eax -; CHECK-X86-NEXT: testw $-32768, %ax # imm = 0x8000 +; CHECK-X86-NEXT: testw $-32768, {{[0-9]+}}(%esp) # imm = 0x8000 ; CHECK-X86-NEXT: jg .LBB19_2 ; CHECK-X86-NEXT: # %bb.1: # %yes ; CHECK-X86-NEXT: calll bar