6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-12-15 04:30:12 +00:00
Code Issues Projects Releases Wiki Activity

Don't emit FP_REG_KILL into a block that just returns. Nothing

Browse Source 
can be live out of the block anyway, so it isn't needed.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48192 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2008-03-10 23:34:12 +00:00
parent a2e9485e34
commit 03fdec04d1
2 changed files with 22 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

25
lib/Target/X86/X86ISelDAGToDAG.cpp
View File

@ -550,7 +550,8 @@ void X86DAGToDAGISel::InstructionSelectBasicBlock(SelectionDAG &DAG) {
DAG.RemoveDeadNodes();
// Emit machine code to BB.
// Emit machine code to BB. This can change 'BB' to the last block being
// inserted into.
ScheduleAndEmitDAG(DAG);
// If we are emitting FP stack code, scan the basic block to determine if this
@ -566,15 +567,27 @@ void X86DAGToDAGISel::InstructionSelectBasicBlock(SelectionDAG &DAG) {
// Scan all of the machine instructions in these MBBs, checking for FP
// stores. (RFP32 and RFP64 will not exist in SSE mode, but RFP80 might.)
MachineFunction::iterator MBBI = FirstMBB;
do {
MachineFunction::iterator EndMBB = BB; ++EndMBB;
for (; MBBI != EndMBB; ++MBBI) {
MachineBasicBlock *MBB = MBBI;
// If this block returns, ignore it. We don't want to insert an FP_REG_KILL
// before the return.
if (!MBB->empty()) {
MachineBasicBlock::iterator EndI = MBB->end();
--EndI;
if (EndI->getDesc().isReturn())
continue;
}
bool ContainsFPCode = false;
for (MachineBasicBlock::iterator I = MBBI->begin(), E = MBBI->end();
for (MachineBasicBlock::iterator I = MBB->begin(), E = MBB->end();
!ContainsFPCode && I != E; ++I) {
if (I->getNumOperands() != 0 && I->getOperand(0).isRegister()) {
const TargetRegisterClass *clas;
for (unsigned op = 0, e = I->getNumOperands(); op != e; ++op) {
if (I->getOperand(op).isRegister() && I->getOperand(op).isDef() &&
TargetRegisterInfo::isVirtualRegister(I->getOperand(op).getReg()) &&
TargetRegisterInfo::isVirtualRegister(I->getOperand(op).getReg()) &&
((clas = RegInfo->getRegClass(I->getOperand(0).getReg())) ==
X86::RFP32RegisterClass ||
clas == X86::RFP64RegisterClass ||
@ -608,11 +621,11 @@ void X86DAGToDAGISel::InstructionSelectBasicBlock(SelectionDAG &DAG) {
}
// Finally, if we found any FP code, emit the FP_REG_KILL instruction.
if (ContainsFPCode) {
BuildMI(*MBBI, MBBI->getFirstTerminator(),
BuildMI(*MBB, MBBI->getFirstTerminator(),
TM.getInstrInfo()->get(X86::FP_REG_KILL));
++NumFPKill;
}
} while (&*(MBBI++) != BB);
}
}
/// EmitSpecialCodeForMain - Emit any code that needs to be executed only in

4
test/CodeGen/X86/2007-07-25-EpilogueBug.ll
View File

@ -1,5 +1,7 @@
; Verify that the addl comes before any popl.
; RUN: llvm-as < %s | llc -mtriple=i686-pc-linux-gnu -mcpu=i386 | \
; RUN: %prcontext ret 1 | grep FP_REG_KILL
; RUN: %prcontext ret 1 | grep popl
; PR1573
%struct.c34006f__TsB = type { i8, i32, i32, %struct.c34006f__TsB___b___XVN }