debuginfo: Add script that allows to conveniently start LLDB in "rust-mode"

Makefile.in

@@ -198,6 +198,8 @@ include $(CFG_SRC_DIR)mk/rustllvm.mk
 include $(CFG_SRC_DIR)mk/docs.mk
 # LLVM
 include $(CFG_SRC_DIR)mk/llvm.mk
+# Rules for installing debugger scripts
+include $(CFG_SRC_DIR)mk/debuggers.mk
 
 ######################################################################
 # Secondary makefiles, conditionalized for speed

mk/clean.mk

@@ -63,6 +63,7 @@ clean-generic-$(2)-$(1):
          -name '*.lib' -o \
          -name '*.dll' -o \
          -name '*.def' -o \
+         -name '*.py' -o \
          -name '*.bc' \
          \) \
          | xargs rm -f
@@ -78,7 +79,7 @@ define CLEAN_HOST_STAGE_N
 
 clean$(1)_H_$(2): \
 	    $$(foreach crate,$$(CRATES),clean$(1)_H_$(2)-lib-$$(crate)) \
-	    $$(foreach tool,$$(TOOLS),clean$(1)_H_$(2)-tool-$$(tool))
+	    $$(foreach tool,$$(TOOLS) $$(DEBUGGER_BIN_SCRIPTS),clean$(1)_H_$(2)-tool-$$(tool))
 	$$(Q)rm -fr $(2)/rt/libbacktrace
 
 clean$(1)_H_$(2)-tool-%:
@@ -98,7 +99,7 @@ define CLEAN_TARGET_STAGE_N
 
 clean$(1)_T_$(2)_H_$(3): \
 	    $$(foreach crate,$$(CRATES),clean$(1)_T_$(2)_H_$(3)-lib-$$(crate)) \
-	    $$(foreach tool,$$(TOOLS),clean$(1)_T_$(2)_H_$(3)-tool-$$(tool))
+	    $$(foreach tool,$$(TOOLS) $$(DEBUGGER_BIN_SCRIPTS),clean$(1)_T_$(2)_H_$(3)-tool-$$(tool))
 	$$(Q)rm -f $$(TLIB$(1)_T_$(2)_H_$(3))/libmorestack.a
 	$$(Q)rm -f $$(TLIB$(1)_T_$(2)_H_$(3))/libcompiler-rt.a
 	$(Q)rm -f $$(TLIB$(1)_T_$(2)_H_$(3))/librun_pass_stage* # For unix

mk/debuggers.mk

@@ -0,0 +1,59 @@
+# Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+# file at the top-level directory of this distribution and at
+# http://rust-lang.org/COPYRIGHT.
+#
+# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+# option. This file may not be copied, modified, or distributed
+# except according to those terms.
+
+######################################################################
+# Copy debugger related scripts
+######################################################################
+
+DEBUGGER_RUSTLIB_ETC_SCRIPTS=lldb_rust_formatters.py
+DEBUGGER_BIN_SCRIPTS=rust-lldb
+
+DEBUGGER_RUSTLIB_ETC_SCRIPTS_ABS=$(foreach script,$(DEBUGGER_RUSTLIB_ETC_SCRIPTS), \
+                                     $(CFG_SRC_DIR)src/etc/$(script))
+DEBUGGER_BIN_SCRIPTS_ABS=$(foreach script,$(DEBUGGER_BIN_SCRIPTS), \
+                             $(CFG_SRC_DIR)src/etc/$(script))
+
+DEBUGGER_SCRIPTS_ALL=$(DEBUGGER_RUSTLIB_ETC_SCRIPTS_ABS) $(DEBUGGER_BIN_SCRIPTS_ABS)
+
+# $(1) - the stage to copy to
+# $(2) - the host triple
+define DEF_INSTALL_DEBUGGER_SCRIPTS_HOST
+
+tmp/install-debugger-scripts$(1)_H_$(2).done: $$(DEBUGGER_SCRIPTS_ALL)
+	$(Q)mkdir -p $$(HBIN$(1)_H_$(2))
+	$(Q)mkdir -p $$(HLIB$(1)_H_$(2))/rustlib/etc
+	$(Q)install $(DEBUGGER_BIN_SCRIPTS_ABS) $$(HBIN$(1)_H_$(2))
+	$(Q)install $(DEBUGGER_RUSTLIB_ETC_SCRIPTS_ABS) $$(HLIB$(1)_H_$(2))/rustlib/etc
+	$(Q)touch $$@
+endef
+
+# Expand host make-targets for all stages
+$(foreach stage,$(STAGES), \
+  $(foreach host,$(CFG_HOST), \
+    $(eval $(call DEF_INSTALL_DEBUGGER_SCRIPTS_HOST,$(stage),$(host)))))
+
+# $(1) is the stage number
+# $(2) is the target triple
+# $(3) is the host triple
+define DEF_INSTALL_DEBUGGER_SCRIPTS_TARGET
+
+tmp/install-debugger-scripts$(1)_T_$(2)_H_$(3).done: $$(DEBUGGER_SCRIPTS_ALL)
+	$(Q)mkdir -p $$(TBIN$(1)_T_$(2)_H_$(3))
+	$(Q)mkdir -p $$(TLIB$(1)_T_$(2)_H_$(3))/rustlib/etc
+	$(Q)install $(DEBUGGER_BIN_SCRIPTS_ABS) $$(TBIN$(1)_T_$(2)_H_$(3))
+	$(Q)install $(DEBUGGER_RUSTLIB_ETC_SCRIPTS_ABS) $$(TLIB$(1)_T_$(2)_H_$(3))/rustlib/etc
+	$(Q)touch $$@
+endef
+
+# Expand target make-targets for all stages
+$(foreach stage,$(STAGES), \
+  $(foreach target,$(CFG_TARGET), \
+    $(foreach host,$(CFG_HOST), \
+      $(eval $(call DEF_INSTALL_DEBUGGER_SCRIPTS_TARGET,$(stage),$(target),$(host))))))

mk/main.mk

@@ -356,7 +356,8 @@ HSREQ$(1)_H_$(3) = $$(HBIN$(1)_H_$(3))/rustc$$(X_$(3))
 else
 HSREQ$(1)_H_$(3) = \
 	$$(HBIN$(1)_H_$(3))/rustc$$(X_$(3)) \
-	$$(MKFILE_DEPS)
+	$$(MKFILE_DEPS) \
+	tmp/install-debugger-scripts$(1)_H_$(3).done
 endif
 
 # Prerequisites for using the stageN compiler to build target artifacts
@@ -370,7 +371,8 @@ TSREQ$(1)_T_$(2)_H_$(3) = \
 SREQ$(1)_T_$(2)_H_$(3) = \
 	$$(TSREQ$(1)_T_$(2)_H_$(3)) \
 	$$(foreach dep,$$(TARGET_CRATES), \
-	    $$(TLIB$(1)_T_$(2)_H_$(3))/stamp.$$(dep))
+	    $$(TLIB$(1)_T_$(2)_H_$(3))/stamp.$$(dep)) \
+	tmp/install-debugger-scripts$(1)_T_$(2)_H_$(3).done
 
 # Prerequisites for a working stageN compiler and complete set of target
 # libraries

mk/prepare.mk

@@ -155,7 +155,7 @@ prepare-base-$(1): PREPARE_DEST_LIB_DIR=$$(PREPARE_DEST_DIR)/$$(CFG_LIBDIR_RELAT
 prepare-base-$(1): PREPARE_DEST_MAN_DIR=$$(PREPARE_DEST_DIR)/share/man/man1
 prepare-base-$(1): prepare-everything-$(1)
 
-prepare-everything-$(1): prepare-host-$(1) prepare-targets-$(1)
+prepare-everything-$(1): prepare-host-$(1) prepare-targets-$(1) prepare-debugger-scripts-$(1)
 
 prepare-host-$(1): prepare-host-tools-$(1)
 
@@ -167,8 +167,13 @@ prepare-host-tools-$(1): \
 prepare-host-dirs-$(1): prepare-maybe-clean-$(1)
 	$$(call PREPARE_DIR,$$(PREPARE_DEST_BIN_DIR))
 	$$(call PREPARE_DIR,$$(PREPARE_DEST_LIB_DIR))
+	$$(call PREPARE_DIR,$$(PREPARE_DEST_LIB_DIR)/rustlib/etc)
 	$$(call PREPARE_DIR,$$(PREPARE_DEST_MAN_DIR))
 
+prepare-debugger-scripts-$(1): prepare-host-dirs-$(1) $(DEBUGGER_SCRIPTS_ALL)
+	$$(Q)$$(PREPARE_BIN_CMD) $(DEBUGGER_BIN_SCRIPTS_ABS) $$(PREPARE_DEST_BIN_DIR)
+	$$(Q)$$(PREPARE_LIB_CMD) $(DEBUGGER_RUSTLIB_ETC_SCRIPTS_ABS) $$(PREPARE_DEST_LIB_DIR)/rustlib/etc
+
 $$(foreach tool,$$(PREPARE_TOOLS), \
   $$(foreach host,$$(CFG_HOST), \
       $$(eval $$(call DEF_PREPARE_HOST_TOOL,$$(tool),$$(PREPARE_STAGE),$$(host),$(1)))))

src/etc/lldb_rust_formatters.py

@@ -69,8 +69,14 @@ def print_struct_val_starting_from(field_start_index, val, internal_dict):
   assert val.GetType().GetTypeClass() == lldb.eTypeClassStruct
 
   t = val.GetType()
-  has_field_names = type_has_field_names(t)
   type_name = extract_type_name(t.GetName())
+  num_children = val.num_children
+
+  if (num_children - field_start_index) == 0:
+    # The only field of this struct is the enum discriminant
+    return type_name
+
+  has_field_names = type_has_field_names(t)
 
   if has_field_names:
       template = "%(type_name)s {\n%(body)s\n}"
@@ -83,8 +89,6 @@ def print_struct_val_starting_from(field_start_index, val, internal_dict):
     # this is a tuple, so don't print the type name
     type_name = ""
 
-  num_children = val.num_children
-
   def render_child(child_index):
     this = ""
     if has_field_names:
@@ -105,7 +109,6 @@ def print_enum_val(val, internal_dict):
 
   assert val.GetType().GetTypeClass() == lldb.eTypeClassUnion
 
-
   if val.num_children == 1:
     # This is either an enum with just one variant, or it is an Option-like enum
     # where the discriminant is encoded in a non-nullable pointer field. We find

src/etc/rust-lldb

@@ -0,0 +1,30 @@
+#!/bin/sh
+# Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+# file at the top-level directory of this distribution and at
+# http://rust-lang.org/COPYRIGHT.
+#
+# Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+# http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+# <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+# option. This file may not be copied, modified, or distributed
+# except according to those terms.
+
+# Exit if anything fails
+set -e
+
+# Create a tempfile containing the LLDB script we want to execute on startup
+TMPFILE=`mktemp /tmp/rust-lldb-commands.XXXXXX`
+
+# Make sure to delete the tempfile no matter what
+trap "rm -f $TMPFILE; exit" INT TERM EXIT
+
+# Find out where to look for the pretty printer Python module
+RUSTC_SYSROOT=`rustc -Zprint-sysroot`
+
+# Write the LLDB script to the tempfile
+echo "command script import \"$RUSTC_SYSROOT/lib/rustlib/etc/lldb_rust_formatters.py\"" >> $TMPFILE
+echo "type summary add --no-value --python-function lldb_rust_formatters.print_val -x \".*\" --category Rust" >> $TMPFILE
+echo "type category enable Rust" >> $TMPFILE
+
+# Call LLDB with the script added to the argument list
+lldb --source-before-file="$TMPFILE" "$@"

src/librustc/session/config.rs

@@ -212,13 +212,14 @@ debugging_opts!(
         FLOWGRAPH_PRINT_LOANS,
         FLOWGRAPH_PRINT_MOVES,
         FLOWGRAPH_PRINT_ASSIGNS,
-        FLOWGRAPH_PRINT_ALL
+        FLOWGRAPH_PRINT_ALL,
+        PRINT_SYSROOT
     ]
     0
 )
 
 pub fn debugging_opts_map() -> Vec<(&'static str, &'static str, u64)> {
-    vec!(("verbose", "in general, enable more debug printouts", VERBOSE),
+    vec![("verbose", "in general, enable more debug printouts", VERBOSE),
      ("time-passes", "measure time of each rustc pass", TIME_PASSES),
      ("count-llvm-insns", "count where LLVM \
                            instrs originate", COUNT_LLVM_INSNS),
@@ -256,7 +257,9 @@ pub fn debugging_opts_map() -> Vec<(&'static str, &'static str, u64)> {
      ("flowgraph-print-assigns", "Include assignment analysis data in \
                        --pretty flowgraph output", FLOWGRAPH_PRINT_ASSIGNS),
      ("flowgraph-print-all", "Include all dataflow analysis data in \
-                       --pretty flowgraph output", FLOWGRAPH_PRINT_ALL))
+                       --pretty flowgraph output", FLOWGRAPH_PRINT_ALL),
+     ("print-sysroot", "Print the sysroot as used by this rustc invocation",
+      PRINT_SYSROOT)]
 }
 
 #[deriving(Clone)]

src/librustc_trans/driver/mod.rs

@@ -75,6 +75,13 @@ fn run_compiler(args: &[String]) {
                 describe_lints(&ls, false);
                 return;
             }
+
+            let sess = build_session(sopts, None, descriptions);
+            if sess.debugging_opt(config::PRINT_SYSROOT) {
+                println!("{}", sess.sysroot().display());
+                return;
+            }
+
             early_error("no input filename given");
         }
         1u => {