add simple sum example

examples/Makefile_EmbedWASM

@@ -0,0 +1,86 @@
+# This makefile embeds an application compiled to WASM into a native C program.
+# The WASM module will be loaded by the WASM runtime.
+
+# Paths
+WAMR_ROOT     := /opt/wamr
+WAMRC         := /opt/wamr-wamrc/wamrc
+IWASM         := /opt/wamr-iwasm/iwasm
+WAMRC_LIB     := /opt/wamr-libvmlib
+IWASM_LIB     := /opt/wamr-libiwasm
+
+WASI_ROOT     := /opt/wasi-sdk
+WASI_CC       := $(WASI_ROOT)/bin/clang
+WASI_CFLAGS   := --target=wasm32-wasi \
+		 --sysroot=$(WASI_ROOT)/share/wasi-sysroot \
+		 -O0 -g -Wall
+
+# Embedding
+EMBED_CC      := gcc
+EMBED_INCL    := -I$(WAMR_ROOT)/core/iwasm/include \
+                 -I$(WAMR_ROOT)/core/iwasm/common \
+		 -I$(WAMR_ROOT)/core/shared/platform/linux \
+		 -I$(WAMR_ROOT)/core/shared/utils \
+		 -I$(WAMR_ROOT)/core/shared/utils/uncommon
+EMBED_SOURCES := $(WAMR_ROOT)/core/shared/utils/uncommon/bh_read_file.c # Not used when reading from buffer
+EMBED_CFLAGS  := -O0 -g -Wall $(EMBED_INCL)
+AOT_LDFLAGS   := -Wl,-rpath,$(WAMRC_LIB)
+AOT_LDLIBS    := -L$(WAMRC_LIB) -lvmlib -lm
+INTER_LDFLAGS := -Wl,-rpath,$(IWASM_LIB)
+INTER_LDLIBS  := -L$(IWASM_LIB) -liwasm -lm
+XXD           := busybox xxd
+
+# Files
+SRCS          := $(wildcard *.c)
+WASMS         := $(SRCS:.c=.wasm)
+CWASMS        := $(SRCS:.c=_wasm.c)
+AOTS          := $(SRCS:.c=.aot)
+OBJS          := $(SRCS:.c=.o)
+DEPS          := $(SRCS:.c=.d)
+HOSTS         := $(SRCS:.c=_host.elf)
+
+
+.PHONY: all build-wasms build-aots build-cwasms build-hosts clean
+
+all: build-wasms build-aots build-cwasms build-hosts
+
+# Compile to wasm bytecode using wasi-sdk
+build-wasms: $(WASMS)
+
+%.wasm: %.c
+	$(WASI_CC) $(WASI_CFLAGS) $< -o $@
+
+# Compile ahead-of-time module using wamrc
+build-aots: $(AOTS)
+
+%.aot: %.wasm
+	$(WAMRC) -o $@ $<
+
+# Convert the .aot files to C-style arrays (to embed them into the resulting host binary)
+build-cwasms: $(CWASMS)
+
+%_wasm.c: %.aot
+	$(XXD) -i $< > $@
+
+# Compile the host that will load and run the compiled wasm module
+# The compiled wasm module is embedded as C-style array
+build-hosts: $(HOSTS)
+
+# The C-style array is called %_aot, e.g. test_aot
+# We have to modify the host to refer to that with the correct name
+%_host.elf: %_wasm.c
+	cp embed/host.c embed/$*_host.c
+	sed -i \
+	    -e "s@__WASM_ARRAY_FILE__@../$*_wasm.c@g" \
+            -e "s@__WASM_ARRAY__@$*_aot@g" \
+            -e "s@__WASM_ARRAY_LEN__@$*_aot_len@g" \
+            embed/$*_host.c
+	$(EMBED_CC) $(EMBED_CFLAGS) embed/$*_host.c -o $@ $(INTER_LDFLAGS) $(INTER_LDLIBS)
+
+clean:
+	rm -f *.wasm
+	rm -f *.aot
+	rm -f *_wasm.c
+	rm -f *.d
+	rm -f *.o
+	rm -f embed/*_host.c
+	rm -f *_host.elf