old_contents: # Copyright lowRISC contributors.
  # Licensed under the Apache License, Version 2.0, see LICENSE for details.
  # SPDX-License-Identifier: Apache-2.0
  
  import os
  
  
  def find_tool(tool_name: str) -> str:
      '''Return a string describing how to invoke the given RISC-V tool
  
      Try to resolve the tool in the following way, stopping after the first
      match:
  
      1. Use the path set in the RV32_TOOL_<tool_name> environment variable.
      2. Use the path set in $TOOLCHAIN_PATH/bin/riscv32-unknown-elf-<tool_name>.
      3. Use riscv32-unknown-elf-<tool_name> and expect it to be in PATH.
  
      In cases (1) and (2), the file path is checked if it exists, and if not, an
      error message is printed.
      '''
      tool_env_var = 'RV32_TOOL_' + tool_name.upper()
      configured_tool_path = os.environ.get(tool_env_var)
      if configured_tool_path is not None:
          if not os.path.exists(configured_tool_path):
              raise RuntimeError('No such file: {!r} (derived from the '
                                 '{!r} environment variable when trying '
                                 'to find the {!r} tool).'.format(
                                     configured_tool_path, tool_env_var,
                                     tool_name))
          return configured_tool_path
  
      expanded = 'riscv32-unknown-elf-' + tool_name
      toolchain_path = os.environ.get('TOOLCHAIN_PATH')
      if toolchain_path is None:
          return expanded
  
      tool_path = os.path.join(toolchain_path, 'bin', expanded)
      if not os.path.exists(tool_path):
          raise RuntimeError('No such file: {!r} (derived from the '
                             'TOOLCHAIN_PATH environment variable when trying '
                             'to find the {!r} tool).'
                             .format(tool_path, tool_name))
  
      return tool_path
  
new_contents: # Copyright lowRISC contributors.
  # Licensed under the Apache License, Version 2.0, see LICENSE for details.
  # SPDX-License-Identifier: Apache-2.0
  
  import os
  
  
  def find_tool(tool_name: str) -> str:
      '''Return a string describing how to invoke the given RISC-V tool
  
      Try to resolve the tool in the following way, stopping after the first
      match:
  
      1. Use the path set in the RV32_TOOL_<tool_name> environment variable.
      2. Use the path set in $TOOLCHAIN_PATH/bin/riscv32-unknown-elf-<tool_name>.
      3. Look for riscv32-unknown-elf-<tool_name> in the system PATH.
      4. Look in the default toolchain install location, /tools/riscv/bin.
  
      For methods (1) and (2), if the expected environment variable is set but
      the tool isn't found, an error is printed. An error is also printed if
      neither environment variables is set and methods (3) and (4) fail.
      '''
      tool_env_var = 'RV32_TOOL_' + tool_name.upper()
      configured_tool_path = os.environ.get(tool_env_var)
      if configured_tool_path is not None:
          if not os.path.exists(configured_tool_path):
              raise RuntimeError('No such file: {!r} (derived from the '
                                 '{!r} environment variable when trying '
                                 'to find the {!r} tool).'.format(
                                     configured_tool_path, tool_env_var,
                                     tool_name))
          return configured_tool_path
  
      expanded = 'riscv32-unknown-elf-' + tool_name
      toolchain_path = os.environ.get('TOOLCHAIN_PATH')
      if toolchain_path is not None:
          tool_path = os.path.join(toolchain_path, 'bin', expanded)
          if not os.path.exists(tool_path):
              raise RuntimeError('No such file: {!r} (derived from the '
                                 'TOOLCHAIN_PATH environment variable when trying '
                                 'to find the {!r} tool).'
                                 .format(tool_path, tool_name))
          return tool_path
  
      default_location = '/tools/riscv/bin'
      paths = os.get_exec_path() + [default_location]
      for exec_path in paths:
          tool_path = os.path.join(exec_path, expanded)
          if os.path.exists(tool_path):
              return tool_path
  
      raise RuntimeError('Unable to find {!r} in PATH or in {!r}. Set the {!r} '
                         'or TOOLCHAIN_PATH environment variable if you '
                         'installed your RISC-V toolchain in an alternate '
                         'location.'
                         .format(expanded, default_location, tool_env_var))
  
subject: Update RISC-V toolchain search to look in default location.