mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-08-22 10:29:35 +00:00
Re-apply 101075 and fix it properly. Just reuse the debug info of the branch instruction being optimized. There is no need to --I which can deref off start of the BB.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101162 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evan Cheng
parent
f23c769294
commit
fc5a03e469
@ -1684,6 +1684,7 @@ bool X86InstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,
|
||||
// Start from the bottom of the block and work up, examining the
|
||||
// terminator instructions.
|
||||
MachineBasicBlock::iterator I = MBB.end();
|
||||
MachineBasicBlock::iterator UnCondBrIter = MBB.end();
|
||||
while (I != MBB.begin()) {
|
||||
--I;
|
||||
if (I->isDebugValue())
|
||||
@ -1701,6 +1702,8 @@ bool X86InstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,
|
||||
|
||||
// Handle unconditional branches.
|
||||
if (I->getOpcode() == X86::JMP_4) {
|
||||
UnCondBrIter = I;
|
||||
|
||||
if (!AllowModify) {
|
||||
TBB = I->getOperand(0).getMBB();
|
||||
continue;
|
||||
@ -1718,10 +1721,11 @@ bool X86InstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,
|
||||
TBB = 0;
|
||||
I->eraseFromParent();
|
||||
I = MBB.end();
|
||||
UnCondBrIter = MBB.end();
|
||||
continue;
|
||||
}
|
||||
|
||||
// TBB is used to indicate the unconditinal destination.
|
||||
// TBB is used to indicate the unconditional destination.
|
||||
TBB = I->getOperand(0).getMBB();
|
||||
continue;
|
||||
}
|
||||
@ -1733,6 +1737,45 @@ bool X86InstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,
|
||||
|
||||
// Working from the bottom, handle the first conditional branch.
|
||||
if (Cond.empty()) {
|
||||
MachineBasicBlock *TargetBB = I->getOperand(0).getMBB();
|
||||
if (AllowModify && UnCondBrIter != MBB.end() &&
|
||||
MBB.isLayoutSuccessor(TargetBB)) {
|
||||
// If we can modify the code and it ends in something like:
|
||||
//
|
||||
// jCC L1
|
||||
// jmp L2
|
||||
// L1:
|
||||
// ...
|
||||
// L2:
|
||||
//
|
||||
// Then we can change this to:
|
||||
//
|
||||
// jnCC L2
|
||||
// L1:
|
||||
// ...
|
||||
// L2:
|
||||
//
|
||||
// Which is a bit more efficient.
|
||||
// We conditionally jump to the fall-through block.
|
||||
BranchCode = GetOppositeBranchCondition(BranchCode);
|
||||
unsigned JNCC = GetCondBranchFromCond(BranchCode);
|
||||
MachineBasicBlock::iterator OldInst = I;
|
||||
|
||||
BuildMI(MBB, UnCondBrIter, MBB.findDebugLoc(I), get(JNCC))
|
||||
.addMBB(UnCondBrIter->getOperand(0).getMBB());
|
||||
BuildMI(MBB, UnCondBrIter, MBB.findDebugLoc(I), get(X86::JMP_4))
|
||||
.addMBB(TargetBB);
|
||||
MBB.addSuccessor(TargetBB);
|
||||
|
||||
OldInst->eraseFromParent();
|
||||
UnCondBrIter->eraseFromParent();
|
||||
|
||||
// Restart the analysis.
|
||||
UnCondBrIter = MBB.end();
|
||||
I = MBB.end();
|
||||
continue;
|
||||
}
|
||||
|
||||
FBB = TBB;
|
||||
TBB = I->getOperand(0).getMBB();
|
||||
Cond.push_back(MachineOperand::CreateImm(BranchCode));
|
||||
|
||||
42
test/CodeGen/X86/2010-04-13-AnalyzeBranchCrash.ll
Normal file
42
test/CodeGen/X86/2010-04-13-AnalyzeBranchCrash.ll
Normal file
@ -0,0 +1,42 @@
|
||||
; RUN: llc < %s -mtriple=i386-apple-darwin -mcpu=core2
|
||||
; rdar://7857830
|
||||
|
||||
%0 = type opaque
|
||||
%1 = type opaque
|
||||
|
||||
define void @t(%0* %self, i8* nocapture %_cmd, %1* %scroller, i32 %hitPart, float %multiplier) nounwind optsize ssp {
|
||||
entry:
|
||||
switch i32 %hitPart, label %if.else [
|
||||
i32 7, label %if.then
|
||||
i32 8, label %if.then
|
||||
]
|
||||
|
||||
if.then: ; preds = %entry, %entry
|
||||
%tmp69 = load float* null, align 4 ; <float> [#uses=1]
|
||||
%cmp19 = icmp eq %1* null, %scroller ; <i1> [#uses=2]
|
||||
%cond = select i1 %cmp19, float %tmp69, float 0.000000e+00 ; <float> [#uses=1]
|
||||
%call36 = call i64 bitcast (i8* (i8*, i8*, ...)* @objc_msgSend to i64 (i8*, i8*)*)(i8* undef, i8* undef) nounwind optsize ; <i64> [#uses=2]
|
||||
br i1 %cmp19, label %cond.true32, label %cond.false39
|
||||
|
||||
cond.true32: ; preds = %if.then
|
||||
%sroa.store.elt68 = lshr i64 %call36, 32 ; <i64> [#uses=1]
|
||||
%0 = trunc i64 %sroa.store.elt68 to i32 ; <i32> [#uses=1]
|
||||
br label %cond.end47
|
||||
|
||||
cond.false39: ; preds = %if.then
|
||||
%1 = trunc i64 %call36 to i32 ; <i32> [#uses=1]
|
||||
br label %cond.end47
|
||||
|
||||
cond.end47: ; preds = %cond.false39, %cond.true32
|
||||
%cond48.in = phi i32 [ %0, %cond.true32 ], [ %1, %cond.false39 ] ; <i32> [#uses=1]
|
||||
%cond48 = bitcast i32 %cond48.in to float ; <float> [#uses=1]
|
||||
%div = fdiv float %cond, undef ; <float> [#uses=1]
|
||||
%div58 = fdiv float %div, %cond48 ; <float> [#uses=1]
|
||||
call void bitcast (i8* (i8*, i8*, ...)* @objc_msgSend to void (i8*, i8*, float)*)(i8* undef, i8* undef, float %div58) nounwind optsize
|
||||
ret void
|
||||
|
||||
if.else: ; preds = %entry
|
||||
ret void
|
||||
}
|
||||
|
||||
declare i8* @objc_msgSend(i8*, i8*, ...)
|
||||
@ -67,3 +67,42 @@ return: ; preds = %entry
|
||||
; CHECK-NEXT: orl 8(%esp), %eax
|
||||
; CHECK-NEXT: je LBB3_2
|
||||
}
|
||||
|
||||
; <rdar://problem/7598384>:
|
||||
;
|
||||
; jCC L1
|
||||
; jmp L2
|
||||
; L1:
|
||||
; ...
|
||||
; L2:
|
||||
; ...
|
||||
;
|
||||
; to:
|
||||
;
|
||||
; jnCC L2
|
||||
; L1:
|
||||
; ...
|
||||
; L2:
|
||||
; ...
|
||||
define float @test4(float %x, float %y) nounwind readnone optsize ssp {
|
||||
entry:
|
||||
%0 = fpext float %x to double ; <double> [#uses=1]
|
||||
%1 = fpext float %y to double ; <double> [#uses=1]
|
||||
%2 = fmul double %0, %1 ; <double> [#uses=3]
|
||||
%3 = fcmp oeq double %2, 0.000000e+00 ; <i1> [#uses=1]
|
||||
br i1 %3, label %bb2, label %bb1
|
||||
|
||||
; CHECK: jne
|
||||
; CHECK-NEXT: jnp
|
||||
; CHECK-NOT: jmp
|
||||
; CHECK: LBB
|
||||
|
||||
bb1: ; preds = %entry
|
||||
%4 = fadd double %2, -1.000000e+00 ; <double> [#uses=1]
|
||||
br label %bb2
|
||||
|
||||
bb2: ; preds = %entry, %bb1
|
||||
%.0.in = phi double [ %4, %bb1 ], [ %2, %entry ] ; <double> [#uses=1]
|
||||
%.0 = fptrunc double %.0.in to float ; <float> [#uses=1]
|
||||
ret float %.0
|
||||
}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user