Add pi demo

cnlohr · Nov 29, 2023 · f3a3087 · f3a3087
1 parent 2ccd085
commit f3a3087
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Showing 5 changed files with 19 additions and 9 deletions.
diff --git a/Makefile b/Makefile
@@ -15,7 +15,7 @@ toolchain : buildroot
 
 everything : toolchain
 	make -C hello_linux deploy
-	# make -C packages/duktapetest deploy
+	#make -C packages/duktapetest deploy
 	make -C packages/coremark deploy
 	cp -a configs/rootfsoverlay/* buildroot/output/target/
 	make -C buildroot

diff --git a/configs/buildroot_config b/configs/buildroot_config
@@ -173,7 +173,7 @@ BR2_PACKAGE_UCLIBC_SUPPORTS=y
 # uClibc Options
 #
 BR2_PACKAGE_UCLIBC=y
-BR2_UCLIBC_CONFIG="package/uclibc/uClibc-ng.config"
+BR2_UCLIBC_CONFIG="uclibc_config"
 BR2_UCLIBC_CONFIG_FRAGMENT_FILES=""
 # BR2_TOOLCHAIN_BUILDROOT_WCHAR is not set
 # BR2_TOOLCHAIN_BUILDROOT_LOCALE is not set

diff --git a/hello_linux/Makefile b/hello_linux/Makefile
@@ -1,12 +1,12 @@
-all : hello_linux
+all : hello_linux pi
 
 PREFIX:=../buildroot/output/host/bin/riscv32-buildroot-linux-uclibc-
 CC:=$(PREFIX)gcc
 OBJDUMP:=$(PREFIX)objdump
 
 # Note:  regymm says to do -fPIE -pie -static, instead of -fPIC
-CFLAGS:=-mabi=ilp32 -fPIE -pie -static -march=rv32ima -Os -s -g
-LDFLAGS:=-Wl,-elf2flt=-r
+CFLAGS:=-mabi=ilp32 -fPIE -pie -static -march=rv32ima -Os -s -g -ffunction-sections -fdata-sections
+LDFLAGS:=-Wl,-elf2flt=-r -Wl,-gc-sections
 
 C_S+=hello_linux.c
 
@@ -19,11 +19,14 @@ hello_linux : hello_linux.c
 	$(CC) $(CFLAGS) $(C_S) $(LDFLAGS) -o $@
 	$(OBJDUMP) -S $@.gdb > $@.S
 
-deploy : hello_linux
+pi : pi.c
+	$(CC) $(CFLAGS) $^ $(LDFLAGS) -o $@
+
+deploy : hello_linux pi
 	cp $^ ../buildroot/output/target/root
 
 rebuild :
 	make -C.. toolchain 
 
 clean :
-	rm -rf hello_linux hello_linux.gdb hello_linux.S
+	rm -rf hello_linux hello_linux.gdb hello_linux.S pi pi.gdb pi.S
diff --git a/hello_linux/hello_linux.c b/hello_linux/hello_linux.c
@@ -3,6 +3,6 @@
 int main( int argc, char ** argv )
 {
 	printf( "Hello, world %08x\n", argc );
-	float f = 7.3f;
-	printf( "f: %f\n", f );
+	float ft = 7.3f;
+	printf( "f: %f\n", ft );
 }
diff --git a/hello_linux/pi.c b/hello_linux/pi.c
@@ -0,0 +1,7 @@
+// https://crypto.stanford.edu/pbc/notes/pi/code.html
+#include <stdio.h>
+int a=10000,b,c=2800,d,e,f[2801],g;int main(){for(;b-c;)f[b++]=a/5;
+for(;d=0,g=c*2;c-=14,printf("%.4d",e+d/a),e=d%a)for(b=c;d+=f[b]*a,
+f[b]=d%--g,d/=g--,--b;d*=b);}
+
+