Developer Improvement: Get code coverage tool working with Hostboot

This commit fixes GCOV code coverage for P9 with GCC 4.9.2

Change-Id: Ie1e7c35f67414531dbd6e7a771ac1529a9ebd59d
RTC: 208351
Reviewed-on: http://rchgit01.rchland.ibm.com/gerrit1/76812
Tested-by: Jenkins Server <pfd-jenkins+hostboot@us.ibm.com>
Reviewed-by: Nicholas E. Bofferding <bofferdn@us.ibm.com>
Reviewed-by: Ilya Smirnov <ismirno@us.ibm.com>
Tested-by: Jenkins OP Build CI <op-jenkins+hostboot@us.ibm.com>
Tested-by: FSP CI Jenkins <fsp-CI-jenkins+hostboot@us.ibm.com>
Tested-by: Jenkins OP HW <op-hw-jenkins+hostboot@us.ibm.com>
Reviewed-by: Daniel M. Crowell <dcrowell@us.ibm.com>

2 files changed, 68 insertions, 15 deletions

diff --git a/src/build/mkrules/cc.rules.mk b/src/build/mkrules/cc.rules.mk
index c89995f82..584b11db4 100644
--- a/src/build/mkrules/cc.rules.mk
+++ b/src/build/mkrules/cc.rules.mk
@@ -5,7 +5,7 @@
 #
 # OpenPOWER HostBoot Project
 #
-# Contributors Listed Below - COPYRIGHT 2013,2017
+# Contributors Listed Below - COPYRIGHT 2013,2019
 # [+] International Business Machines Corp.
 #
 #
@@ -31,11 +31,27 @@ $(OBJDIR)/%.list : $(OBJDIR)/%.o
 	$(C2) "    OBJDUMP    $(notdir $<)"
 	$(C1)$(OBJDUMP) -rdlCS $< > $@
 
+# SOURCE_FILE and INCLUDE_DIRS are variables that are either absolute
+# paths to the .C file being compiled and the include directories if
+# we're building with gcov, or else they are relative paths
+# otherwise. The key thing to remember is that they are lazily
+# expanded, so they're relevant to whatever rule they're used in. We
+# don't want to always have absolute paths because of build
+# performance and because it causes the build output with
+# BUILD_VERBOSE to be larger and less readable.
+ifdef HOSTBOOT_PROFILE
+SOURCE_FILE=$(shell readlink -f $<)
+INCLUDE_DIRS=$(shell $(ROOTPATH)/src/build/tools/cflags.sh $(INCFLAGS))
+else
+SOURCE_FILE=$<
+INCLUDE_DIRS=$(INCFLAGS)
+endif
+
 $(OBJDIR)/%.o : %.C
 	@mkdir -p $(OBJDIR)
 	$(C2) "    CXX        $(notdir $<)"
-	$(C1)$(CXX) -c $(call FLAGS_FILTER, $(CXXFLAGS), $<) $< \
-	            -o $@.trace $(INCFLAGS) -iquote .
+	$(C1)$(CXX) -c $(call FLAGS_FILTER, $(CXXFLAGS), $<) $(SOURCE_FILE) \
+	            -o $@.trace $(INCLUDE_DIRS) -iquote .
 	$(C1)$(TRACE_HASHER) $@ $(TRACE_FLAGS)
 	@rm $@.trace
 
@@ -43,7 +59,8 @@ $(OBJDIR)/%.o : %.C
 $(OBJDIR)/%.o : %.cc
 	@mkdir -p $(OBJDIR)
 	$(C2) "    CXX        $(notdir $<)"
-	$(C1)$(CXX) -c $(CXXFLAGS) $< -o $@.trace $(INCFLAGS) -iquote .
+	$(C1)$(CXX) -c $(CXXFLAGS) $(SOURCE_FILE) -o $@.trace \
+	               $(INCLUDE_DIRS) -iquote .
 	$(C1)$(TRACE_HASHER) $@ $(TRACE_FLAGS)
 	@rm $@.trace
 
@@ -54,12 +71,12 @@ $(OBJDIR)/%.o : %.c
 # CC_OVERRIDE is set in the makefile of the component
 ifndef CC_OVERRIDE
 	$(C2) "    CC         $(notdir $<)"
-	$(C1)$(CC) -c $(call FLAGS_FILTER, $(CFLAGS), $<) $< \
-	           -o $@.trace $(INCFLAGS) -iquote .
+	$(C1)$(CC) -c $(call FLAGS_FILTER, $(CFLAGS), $<) $(SOURCE_FILE) \
+	           -o $@.trace $(INCLUDE_DIRS) -iquote .
 else
 	$(C2) "    CXX        $(notdir $<)"
-	$(C1)$(CXX) -c $(call FLAGS_FILTER, $(CXXFLAGS), $<) $< \
-	            -o $@.trace $(INCFLAGS) -iquote .
+	$(C1)$(CXX) -c $(call FLAGS_FILTER, $(CXXFLAGS), $<) $(SOURCE_FILE) \
+	            -o $@.trace $(INCLUDE_DIRS) -iquote .
 endif
 	$(C1)$(TRACE_HASHER) $@ $(TRACE_FLAGS)
 	@rm $@.trace
diff --git a/src/build/mkrules/gcov.env.mk b/src/build/mkrules/gcov.env.mk
index 8ddcd3ef6..edce52a24 100644
--- a/src/build/mkrules/gcov.env.mk
+++ b/src/build/mkrules/gcov.env.mk
@@ -5,7 +5,9 @@
 #
 # OpenPOWER HostBoot Project
 #
-# COPYRIGHT International Business Machines Corp. 2013,2014
+# Contributors Listed Below - COPYRIGHT 2013,2019
+# [+] International Business Machines Corp.
+#
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -26,21 +28,44 @@
 #     Configuration of the GCOV settings.
 
 GCOVDIR = $(ROOTPATH)/obj/gcov
+vpath %.C $(ROOTPATH)/src/sys/prof
 
 ifdef MODULE
-GCOVNAME = $(MODULE).lcov
+
+# Don't profile HBRT modules to keep size down
+ifdef HOSTBOOT_RUNTIME
+HOSTBOOT_PROFILE=
+endif
+
+## We don't want certain modules to be profiled (HBB, HBRT).
+
+# This is replacing spaces with colons so that we can get an exact
+# match on the module name in the list of unprofilable modules with
+# findstring, which otherwise would find matches on "partial"
+# substrings (i.e. we don't want to deprofile module ABC just because
+# module ABCD is blacklisted, so we create a blacklist of modules
+# separated by colons and search for :ABC:).
+null :=
+MODULE_PROFILE_BLACKLIST:=:$(subst ${null} ${null},:,$(BASE_MODULES_GCOV_BLACKLIST) $(RUNTIME_MODULES_GCOV_BLACKLIST)):
+
+ifneq (,$(findstring :$(MODULE):,$(MODULE_PROFILE_BLACKLIST)))
+HOSTBOOT_PROFILE=
+endif
+
+GCOVNAME := $(MODULE).lcov
+
 ifndef TESTS
 ifdef HOSTBOOT_PROFILE
-vpath %.C $(ROOTPATH)/src/sys/prof
 OBJS := gcov.o $(OBJS)
 endif
 endif
 else
-GCOVNAME = $(notdir $(shell pwd)).lcov
+GCOVNAME := $(notdir $(shell pwd)).lcov
 endif
 
-## Disable coverage on test cases, any directory that sets
-## HOSTBOOT_PROFILE_NO_INSTRUMENT or any file that has 'gcov' in the name.
+## Disable coverage on test cases or any directory that sets
+## HOSTBOOT_PROFILE_NO_INSTRUMENT
+
 ifndef TESTS
 ifdef HOSTBOOT_PROFILE
 ifndef HOSTBOOT_PROFILE_NO_INSTRUMENT
@@ -59,5 +84,16 @@ endif
 ## Reduce the optimization level when profiling is enabled to ensure the
 ## base image fits in 512k still.
 ifdef HOSTBOOT_PROFILE
-OPT_LEVEL = -Os
+# We're not doing this right now because it causes linker errors in
+# various parts of hostboot with or without gcov (i.e. functions that
+# the code relies on being inlined are not; some const statics that
+# aren't defined in a compilation unit have linker references, etc.)
+# and it also causes the image to be generated incorrectly (symbol
+# names are wrong, calls to functions named things like __savegpr_rXX
+# are emitted but the functions themselves aren't and so you end up
+# jumping into an area of zeroes, ...). We should come back to this
+# later and fix, we might be able to profile more of hostboot with the
+# space savings that -Os could give.
+
+#OPT_LEVEL = -Os
 endif