diff options
Diffstat (limited to 'llvm')
| -rw-r--r-- | llvm/lib/CodeGen/XRayInstrumentation.cpp | 11 | ||||
| -rw-r--r-- | llvm/test/CodeGen/X86/xray-empty-firstmbb.mir | 23 | ||||
| -rw-r--r-- | llvm/test/CodeGen/X86/xray-empty-function.mir | 13 |
3 files changed, 45 insertions, 2 deletions
diff --git a/llvm/lib/CodeGen/XRayInstrumentation.cpp b/llvm/lib/CodeGen/XRayInstrumentation.cpp index 570b2edc005..63bd762eeb2 100644 --- a/llvm/lib/CodeGen/XRayInstrumentation.cpp +++ b/llvm/lib/CodeGen/XRayInstrumentation.cpp @@ -129,7 +129,15 @@ bool XRayInstrumentation::runOnMachineFunction(MachineFunction &MF) { return false; // Function is too small. } - auto &FirstMBB = *MF.begin(); + // We look for the first non-empty MachineBasicBlock, so that we can insert + // the function instrumentation in the appropriate place. + auto MBI = + find_if(MF, [&](const MachineBasicBlock &MBB) { return !MBB.empty(); }); + if (MBI == MF.end()) + return false; // The function is empty. + + auto *TII = MF.getSubtarget().getInstrInfo(); + auto &FirstMBB = *MBI; auto &FirstMI = *FirstMBB.begin(); if (!MF.getSubtarget().isXRaySupported()) { @@ -142,7 +150,6 @@ bool XRayInstrumentation::runOnMachineFunction(MachineFunction &MF) { // First, insert an PATCHABLE_FUNCTION_ENTER as the first instruction of the // MachineFunction. - auto *TII = MF.getSubtarget().getInstrInfo(); BuildMI(FirstMBB, FirstMI, FirstMI.getDebugLoc(), TII->get(TargetOpcode::PATCHABLE_FUNCTION_ENTER)); diff --git a/llvm/test/CodeGen/X86/xray-empty-firstmbb.mir b/llvm/test/CodeGen/X86/xray-empty-firstmbb.mir new file mode 100644 index 00000000000..746ee157387 --- /dev/null +++ b/llvm/test/CodeGen/X86/xray-empty-firstmbb.mir @@ -0,0 +1,23 @@ +# RUN: llc -run-pass xray-instrumentation -mtriple=x86_64-unknown-linux-gnu -o - %s | FileCheck %s +# +# Make sure we can handle empty first basic blocks. + +--- | + + define i32 @foo() noinline uwtable "xray-instruction-threshold"="1" { + entry: + unreachable + } + +... + +--- +name: foo +tracksRegLiveness: true +liveins: + - { reg: '%edi'} +body: | + bb.0.entry: + liveins: %edi + ; CHECK-NOT: PATCHABLE_FUNCTION_ENTER +... diff --git a/llvm/test/CodeGen/X86/xray-empty-function.mir b/llvm/test/CodeGen/X86/xray-empty-function.mir new file mode 100644 index 00000000000..3229c93bed9 --- /dev/null +++ b/llvm/test/CodeGen/X86/xray-empty-function.mir @@ -0,0 +1,13 @@ +# RUN: llc -run-pass xray-instrumentation -mtriple=x86_64-unknown-linux-gnu -o - %s | FileCheck %s +# +# Make sure we can handle empty functions. +--- +name: empty +tracksRegLiveness: true +liveins: + - { reg: '%edi'} +body: | + bb.0: + ; CHECK-NOT: PATCHABLE_FUNCTION_ENTER +... + |
