diff options
| -rw-r--r-- | lib/CodeGen/MachineVerifier.cpp | 20 | ||||
| -rw-r--r-- | lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp | 5 | ||||
| -rw-r--r-- | test/CodeGen/ARM/constants.ll | 2 |
3 files changed, 23 insertions, 4 deletions
diff --git a/lib/CodeGen/MachineVerifier.cpp b/lib/CodeGen/MachineVerifier.cpp index f3e310c..852c169 100644 --- a/lib/CodeGen/MachineVerifier.cpp +++ b/lib/CodeGen/MachineVerifier.cpp @@ -580,7 +580,15 @@ MachineVerifier::visitMachineBasicBlockBefore(const MachineBasicBlock *MBB) { ++MBBI; if (MBBI == MF->end()) { report("MBB conditionally falls through out of function!", MBB); - } if (MBB->succ_size() != 2) { + } if (MBB->succ_size() == 1) { + // A conditional branch with only one successor is weird, but allowed. + if (&*MBBI != TBB) + report("MBB exits via conditional branch/fall-through but only has " + "one CFG successor!", MBB); + else if (TBB != *MBB->succ_begin()) + report("MBB exits via conditional branch/fall-through but the CFG " + "successor don't match the actual successor!", MBB); + } else if (MBB->succ_size() != 2) { report("MBB exits via conditional branch/fall-through but doesn't have " "exactly two CFG successors!", MBB); } else if (!matchPair(MBB->succ_begin(), TBB, MBBI)) { @@ -600,7 +608,15 @@ MachineVerifier::visitMachineBasicBlockBefore(const MachineBasicBlock *MBB) { } else if (TBB && FBB) { // Block conditionally branches somewhere, otherwise branches // somewhere else. - if (MBB->succ_size() != 2) { + if (MBB->succ_size() == 1) { + // A conditional branch with only one successor is weird, but allowed. + if (FBB != TBB) + report("MBB exits via conditional branch/branch through but only has " + "one CFG successor!", MBB); + else if (TBB != *MBB->succ_begin()) + report("MBB exits via conditional branch/branch through but the CFG " + "successor don't match the actual successor!", MBB); + } else if (MBB->succ_size() != 2) { report("MBB exits via conditional branch/branch but doesn't have " "exactly two CFG successors!", MBB); } else if (!matchPair(MBB->succ_begin(), TBB, FBB)) { diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp index ae2b329..f3cf758 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp @@ -1601,7 +1601,10 @@ void SelectionDAGBuilder::visitSwitchCase(CaseBlock &CB, // Update successor info addSuccessorWithWeight(SwitchBB, CB.TrueBB, CB.TrueWeight); - addSuccessorWithWeight(SwitchBB, CB.FalseBB, CB.FalseWeight); + // TrueBB and FalseBB are always different unless the incoming IR is + // degenerate. This only happens when running llc on weird IR. + if (CB.TrueBB != CB.FalseBB) + addSuccessorWithWeight(SwitchBB, CB.FalseBB, CB.FalseWeight); // Set NextBlock to be the MBB immediately after the current one, if any. // This is used to avoid emitting unnecessary branches to the next block. diff --git a/test/CodeGen/ARM/constants.ll b/test/CodeGen/ARM/constants.ll index f4c1b5a..0ac8b48 100644 --- a/test/CodeGen/ARM/constants.ll +++ b/test/CodeGen/ARM/constants.ll @@ -1,4 +1,4 @@ -; RUN: llc < %s -mtriple=armv4t-unknown-linux-gnueabi -disable-cgp-branch-opts | FileCheck %s +; RUN: llc < %s -mtriple=armv4t-unknown-linux-gnueabi -disable-cgp-branch-opts -verify-machineinstrs | FileCheck %s define i32 @f1() { ; CHECK: f1 |