Toolchain: Allow toolchain compilation for i386 targets

Fix GCC flags that were x86_64 specific

libc/CMakeLists.txt

@@ -28,7 +28,7 @@ set(LIBC_SOURCES
 	termios.cpp
 	time.cpp
 	unistd.cpp
-	math.S
+	math.cpp
 	icxxabi.cpp
 
 	../BAN/BAN/Assert.cpp

libc/arch/i386/crt0.S

@@ -0,0 +1,33 @@
+.section .text
+
+.global _start
+_start:
+	# zero out stack frame
+	pushl $0
+	pushl $0
+	movl %esp, %ebp
+
+	# FIXME: handle stack alignment
+	ud2
+
+	# push argc, argv, environ for call to main
+	pushl %edx
+	pushl %esi
+	pushl %edi
+
+	# initialize libc
+	pushl %edx
+	call _init_libc
+	addl $4, %esp
+
+	# call global constructos
+	call _init
+
+	# call main, arguments are already on stack
+	call main
+
+	# cleanly exit the process
+	pushl %eax
+	call exit
+
+.size _start, . - _start

libc/arch/i386/crti.S

@@ -0,0 +1,16 @@
+/* i386 crti.s */
+.section .init
+.global _init
+.type _init, @function
+_init:
+	pushl %ebp
+	movl %esp, %ebp
+	/* gcc will nicely put the contents of crtbegin.o's .init section here. */
+
+.section .fini
+.global _fini
+.type _fini, @function
+_fini:
+	pushl %ebp
+	movl %esp, %ebp
+	/* gcc will nicely put the contents of crtbegin.o's .fini section here. */

libc/arch/i386/crtn.S

@@ -0,0 +1,10 @@
+/* i386 crtn.s */
+.section .init
+	/* gcc will nicely put the contents of crtend.o's .init section here. */
+	popl %ebp
+	ret
+
+.section .fini
+	/* gcc will nicely put the contents of crtend.o's .fini section here. */
+	popl %ebp
+	ret

libc/math.S

@@ -1,26 +0,0 @@
-
-.global floorl;
-floorl:
-	fldt	8(%rsp)
-
-	fnstenv	-28(%rsp)		/* store fpu environment */
-
-	/* We use here %edx although only the low 1 bits are defined.
-	  But none of the operations should care and they are faster
-	  than the 16 bit operations.  */
-	movl	$0x400,%edx		/* round towards -oo */
-	orl	-28(%rsp),%edx
-	andl	$0xf7ff,%edx
-	movl	%edx,-32(%rsp)
-	fldcw	-32(%rsp)		/* load modified control word */
-
-	frndint				/* round */
-
-	/* Preserve "invalid" exceptions from sNaN input.  */
-	fnstsw
-	andl	$0x1, %eax
-	orl	%eax, -24(%rsp)
-
-	fldenv	-28(%rsp)		/* restore original environment */
-
-	ret

libc/math.cpp

@@ -0,0 +1,63 @@
+#include <math.h>
+
+#define BUILTINS1(func) \
+	float func##f(float a) { return __builtin_##func##f(a); } \
+	double func(double a) { return __builtin_##func(a); } \
+	long double func##l(long double a) { return __builtin_##func##l(a); }
+
+#define BUILTINS2(func) \
+	float func##f(float a, float b) { return __builtin_##func##f(a, b); } \
+	double func(double a, double b) { return __builtin_##func(a, b); } \
+	long double func##l(long double a, long double b) { return __builtin_##func##l(a, b); } \
+
+__BEGIN_DECLS
+
+BUILTINS1(acos)
+BUILTINS1(acosh)
+BUILTINS1(asin)
+BUILTINS1(asinh)
+BUILTINS1(atan)
+BUILTINS2(atan2)
+BUILTINS1(atanh)
+BUILTINS1(cbrt)
+BUILTINS1(ceil)
+BUILTINS2(copysign)
+BUILTINS1(cos)
+BUILTINS1(cosh)
+BUILTINS1(erf)
+BUILTINS1(erfc)
+BUILTINS1(exp)
+BUILTINS1(exp2)
+BUILTINS1(expm1)
+BUILTINS1(fabs)
+BUILTINS2(fdim)
+BUILTINS1(floor)
+BUILTINS2(fmax)
+BUILTINS2(fmin)
+BUILTINS2(fmod)
+BUILTINS2(hypot)
+BUILTINS1(j0)
+BUILTINS1(j1)
+BUILTINS1(lgamma)
+BUILTINS1(log)
+BUILTINS1(log10)
+BUILTINS1(log1p)
+BUILTINS1(log2)
+BUILTINS1(logb)
+BUILTINS1(nearbyint)
+BUILTINS2(nextafter)
+BUILTINS2(pow)
+BUILTINS2(remainder)
+BUILTINS1(rint)
+BUILTINS1(round)
+BUILTINS1(sin)
+BUILTINS1(sinh)
+BUILTINS1(sqrt)
+BUILTINS1(tan)
+BUILTINS1(tanh)
+BUILTINS1(tgamma)
+BUILTINS1(trunc)
+BUILTINS1(y0)
+BUILTINS1(y1)
+
+__END_DECLS

toolchain/build.sh

@@ -55,10 +55,16 @@ if [[ -z ${MAKE_JOBS:x} ]]; then
 	MAKE_JOBS="-j$(nproc)"
 fi
 
+if [ $BANAN_ARCH = "x86_64" ]; then
+	XCFLAGS="-g -O2 -mcmodel=large -mno-red-zone"
+else
+	XCFLAGS="-g -O2"
+fi
+
 enter_clean_build () {
-	rm -rf build
+	rm -rf build-$BANAN_ARCH
-	mkdir build
+	mkdir build-$BANAN_ARCH
-	cd build
+	cd build-$BANAN_ARCH
 }
 
 build_binutils () {
@@ -110,7 +116,7 @@ build_gcc () {
 		--enable-languages=c,c++
 
 	make $MAKE_JOBS all-gcc
-	make $MAKE_JOBS all-target-libgcc CFLAGS_FOR_TARGET='-g -O2 -mcmodel=large -mno-red-zone'
+	make $MAKE_JOBS all-target-libgcc CFLAGS_FOR_TARGET="$XCFLAGS"
 	make install-gcc
 	make install-target-libgcc
 }
@@ -142,13 +148,13 @@ build_grub () {
 }
 
 build_libstdcpp () {
-	if ! [[ -d $BANAN_BUILD_DIR/toolchain/$GCC_VERSION/build ]]; then
+	if ! [[ -d $BANAN_BUILD_DIR/toolchain/$GCC_VERSION/build-$BANAN_ARCH ]]; then
 		echo "You have to build gcc first"
 		exit 1
 	fi
 
-	cd $BANAN_BUILD_DIR/toolchain/$GCC_VERSION/build
+	cd $BANAN_BUILD_DIR/toolchain/$GCC_VERSION/build-$BANAN_ARCH
-	make $MAKE_JOBS all-target-libstdc++-v3 CFLAGS_FOR_TARGET='-g -O2 -mcmodel=large -mno-red-zone'
+	make $MAKE_JOBS all-target-libstdc++-v3 CFLAGS_FOR_TARGET="$XCFLAGS"
 	make install-target-libstdc++-v3
 }
 
@@ -162,13 +168,14 @@ echo "Creating dummy sysroot"
 mkdir -p $BANAN_SYSROOT/usr
 cp -r $BANAN_ROOT_DIR/libc/include $BANAN_SYSROOT/usr/include
 
-# Cleanup all old files from toolchain prefix
-rm -rf $BANAN_TOOLCHAIN_PREFIX
-
 mkdir -p $BANAN_BUILD_DIR/toolchain
 build_binutils
 build_gcc
+
+# Grub is only needed for UEFI (x86_64)
+if [ $BANAN_ARCH = "x86_64" ]; then
 	build_grub
+fi
 
 # delete sysroot and install libc
 rm -r $BANAN_SYSROOT