Index: lib/Target/AMDGPU/AMDGPU.td =================================================================== --- lib/Target/AMDGPU/AMDGPU.td +++ lib/Target/AMDGPU/AMDGPU.td @@ -325,7 +325,7 @@ "amdgpu-debugger-insert-nops", "DebuggerInsertNops", "true", - "Insert two nop instructions for each high level source statement" + "Insert one nop instruction for each high level source statement" >; def FeatureDebuggerReserveTrapRegs : SubtargetFeature< Index: lib/Target/AMDGPU/SIDebuggerInsertNops.cpp =================================================================== --- lib/Target/AMDGPU/SIDebuggerInsertNops.cpp +++ lib/Target/AMDGPU/SIDebuggerInsertNops.cpp @@ -8,20 +8,18 @@ //===----------------------------------------------------------------------===// // /// \file -/// \brief Inserts two nop instructions for each high level source statement for +/// \brief Inserts one nop instruction for each high level source statement for /// debugger usage. /// /// Tools, such as debugger, need to pause execution based on user input (i.e. -/// breakpoint). In order to do this, two nop instructions are inserted for each -/// high level source statement: one before first isa instruction of high level -/// source statement, and one after last isa instruction of high level source -/// statement. Further, debugger may replace nop instructions with trap -/// instructions based on user input. +/// breakpoint). In order to do this, one nop instruction is inserted before the +/// first isa instruction of each high level source statement. Further, debugger +/// may replace nop instructions with trap instructions based on user input. // //===----------------------------------------------------------------------===// #include "SIInstrInfo.h" -#include "llvm/ADT/DenseMap.h" +#include "llvm/ADT/DenseSet.h" #include "llvm/CodeGen/MachineFunction.h" #include "llvm/CodeGen/MachineFunctionPass.h" #include "llvm/CodeGen/MachineInstrBuilder.h" @@ -69,44 +67,24 @@ const SIInstrInfo *TII = static_cast(MF.getSubtarget().getInstrInfo()); - // Mapping from high level source statement line number to last corresponding - // isa instruction. - DenseMap LineToInst; - // Insert nop instruction before first isa instruction of each high level - // source statement and collect last isa instruction for each high level - // source statement. + // Set containing line numbers that have nop inserted. + DenseSet NopInserted; + for (auto &MBB : MF) { for (auto MI = MBB.begin(); MI != MBB.end(); ++MI) { + // Skip DBG_VALUE instructions and instructions without location. if (MI->isDebugValue() || !MI->getDebugLoc()) continue; + // Insert nop instruction if line number does not have nop inserted. auto DL = MI->getDebugLoc(); - auto CL = DL.getLine(); - auto LineToInstEntry = LineToInst.find(CL); - if (LineToInstEntry == LineToInst.end()) { + if (NopInserted.find(DL.getLine()) == NopInserted.end()) { BuildMI(MBB, *MI, DL, TII->get(AMDGPU::S_NOP)) .addImm(0); - LineToInst.insert(std::make_pair(CL, MI)); - } else { - LineToInstEntry->second = MI; + NopInserted.insert(DL.getLine()); } } } - // Insert nop instruction after last isa instruction of each high level source - // statement. - for (auto const &LineToInstEntry : LineToInst) { - auto MBB = LineToInstEntry.second->getParent(); - auto DL = LineToInstEntry.second->getDebugLoc(); - MachineBasicBlock::iterator MI = LineToInstEntry.second; - if (MI->getOpcode() != AMDGPU::S_ENDPGM) - BuildMI(*MBB, *(++MI), DL, TII->get(AMDGPU::S_NOP)) - .addImm(0); - } - // Insert nop instruction before prologue. - MachineBasicBlock &MBB = MF.front(); - MachineInstr &MI = MBB.front(); - BuildMI(MBB, MI, DebugLoc(), TII->get(AMDGPU::S_NOP)) - .addImm(0); return true; } Index: test/CodeGen/AMDGPU/debugger-insert-nops.ll =================================================================== --- test/CodeGen/AMDGPU/debugger-insert-nops.ll +++ test/CodeGen/AMDGPU/debugger-insert-nops.ll @@ -1,18 +1,15 @@ -; RUN: llc -mtriple=amdgcn--amdhsa -mcpu=fiji -mattr=+amdgpu-debugger-insert-nops -verify-machineinstrs < %s | FileCheck %s +; RUN: llc -O0 -mtriple=amdgcn--amdhsa -mcpu=fiji -mattr=+amdgpu-debugger-insert-nops -verify-machineinstrs < %s | FileCheck %s -; CHECK: test01.cl:2:3 +; CHECK: test01.cl:2:{{[0-9]+}} ; CHECK-NEXT: s_nop 0 -; CHECK: s_nop 0 -; CHECK-NEXT: test01.cl:3:3 +; CHECK: test01.cl:3:{{[0-9]+}} ; CHECK-NEXT: s_nop 0 -; CHECK: s_nop 0 -; CHECK-NEXT: test01.cl:4:3 +; CHECK: test01.cl:4:{{[0-9]+}} ; CHECK-NEXT: s_nop 0 -; CHECK: s_nop 0 -; CHECK-NEXT: test01.cl:5:1 +; CHECK: test01.cl:5:{{[0-9]+}} ; CHECK-NEXT: s_nop 0 ; CHECK-NEXT: s_endpgm