klib: add memchr

Makefile

@@ -72,11 +72,11 @@ include $(AM_HOME)/scripts/$(ARCH).mk
 BUILDDIR := $(DST_DIR)
 COMMON_CFLAGS := $(CFLAGS) -g -O3 -MMD -Wall \
                  -fno-asynchronous-unwind-tables -fno-builtin -fno-stack-protector \
-                 -Wno-main -U_FORTIFY_SOURCE -fvisibility=hidden
+                 -U_FORTIFY_SOURCE -fvisibility=hidden -fno-exceptions -std=gnu11 
 INTERFACE_LDFLAGS += -z noexecstack
 INTERFACE_CFLAGS += -fno-asynchronous-unwind-tables \
                     -fno-builtin -fno-stack-protector \
-                    -Wno-main -U_FORTIFY_SOURCE -fvisibility=hidden
+                    -U_FORTIFY_SOURCE -fvisibility=hidden -fno-exceptions
 ### Build libam
 #### Include archetecture specific build flags
 COMMON_CFLAGS += -D__ARCH_$(shell echo $(ARCH) | tr a-z A-Z | tr - _) \
@@ -90,7 +90,7 @@ AM_CFLAGS += $(COMMON_CFLAGS) $(addprefix -I, $(AM_INCPATH))
 AM_INTERFACE_INCPATH += $(AM_HOME)/am/include $(AM_HOME)/klib/include
 AM_INTERFACE_CFLAGS += 
                        
-AM_INTERFACE_LDFLAGS += -lm -lam-$(ARCH)
+AM_INTERFACE_LDFLAGS += -lam-$(ARCH)
 
 $(eval $(call ADD_LIBRARY,$(LIB_BUILDDIR)/libam-$(ARCH).a,AM_))
 
@@ -115,6 +115,7 @@ INTERFACE_INCPATH += $(sort $(KLIB_INTERFACE_INCPATH) $(AM_INTERFACE_INCPATH))
 # TODO: Use sort here will cause error on seperated flags, such as: -e _start
 # but without sort, duplicated flags will not be removed.
 INTERFACE_CFLAGS += $(addprefix -I, $(INTERFACE_INCPATH:%=$(INC_INSTALLDIR))) $(sort $(KLIB_INTERFACE_CFLAGS) $(AM_INTERFACE_CFLAGS))
+INTERFACE_CXXFLAGS += $(INTERFACE_CFLAGS) $(addprefix -I, $(INTERFACE_INCPATH:%=$(INC_INSTALLDIR)))
 INTERFACE_LDFLAGS += -L$(LIB_INSTALLDIR) $(sort $(KLIB_INTERFACE_LDFLAGS) $(AM_INTERFACE_LDFLAGS))
 
 EXPORT_FLAGS_FILE := $(LIB_INSTALLDIR)/make/flags-$(ARCH).mk
@@ -129,7 +130,7 @@ $(EXPORT_HELPERS): $(LIB_INSTALLDIR)/make/%: scripts/helpers/%
 	@install -dm755 $(dir $@)
 	@install -Dm644 $< $(dir $@)
 
-export INTERFACE_CFLAGS INTERFACE_INCPATH INTERFACE_LDFLAGS
+export INTERFACE_CFLAGS INTERFACE_CXXFLAGS INTERFACE_ASFLAGS INTERFACE_INCPATH INTERFACE_LDFLAGS
 $(EXPORT_FLAGS_FILE):
 	@echo + INSTALL $(patsubst $(INSTALLDIR)/%,%,$@)
 	@install -Dm644 <(printf $(EXPORT_FLAGS_TEMPLATE)) $(EXPORT_FLAGS_FILE)

am/src/platform/nemu/trm.c

@@ -22,6 +22,7 @@ void halt(int code) {
   while (1);
 }
 
+
 void _trm_init() {
   heap_alloc_ptr = heap.start;
   int ret = main(mainargs);

am/src/riscv/nemu/start.S

@@ -5,4 +5,7 @@
 _start:
   mv s0, zero
   la sp, _stack_pointer
-  jal _trm_init
+
+  lui t0, %hi(_trm_init)   # Load upper 20 bits
+  addi t0, t0, %lo(_trm_init)  # Add lower 12 bits
+  jalr ra, t0, 0           # Jump and link register

klib/include/klib.h

@@ -24,6 +24,7 @@ char *strcpy(char *dst, const char *src);
 char *strncpy(char *dst, const char *src, size_t n);
 int strcmp(const char *s1, const char *s2);
 int strncmp(const char *s1, const char *s2, size_t n);
+void *memchr(const void *src, int c, size_t n);
 
 
 //stdlib.h

klib/src/stdlib.c

@@ -54,4 +54,31 @@ void *malloc(size_t size) {
 void free(void *ptr) {
 }
 
+#include <stdint.h>
+#include <limits.h>
+
+#define SS (sizeof(size_t))
+#define ALIGN (sizeof(size_t)-1)
+#define ONES ((size_t)-1/UCHAR_MAX)
+#define HIGHS (ONES * (UCHAR_MAX/2+1))
+#define HASZERO(x) ((x)-ONES & ~(x) & HIGHS)
+
+void *memchr(const void *src, int c, size_t n)
+{
+	const unsigned char *s = src;
+	c = (unsigned char)c;
+#ifdef __GNUC__
+	for (; ((uintptr_t)s & ALIGN) && n && *s != c; s++, n--);
+	if (n && *s != c) {
+		typedef size_t __attribute__((__may_alias__)) word;
+		const word *w;
+		size_t k = ONES * c;
+		for (w = (const void *)s; n>=SS && !HASZERO(*w^k); w++, n-=SS);
+		s = (const void *)w;
+	}
+#endif
+	for (; n && *s != c; s++, n--);
+	return n ? (void *)s : 0;
+}
+
 #endif

scripts/isa/riscv.mk

@@ -1,6 +1,9 @@
-AM_CFLAGS        += -static -fno-pic -march=rv64g -mcmodel=medany  -mstrict-align
-AM_ASFLAGS       += -static -fno-pic -march=rv32g_zicsr -mcmodel=medany -O0
-AM_LDFLAGS       += -melf64lriscv -O2
+AM_CFLAGS        += -static -fno-pic -mstrict-align -ffreestanding
+AM_ASFLAGS       += -static -fno-pic -O0
+
+INTERFACE_CFLAGS += -static -mcmodel=medany -mstrict-align -ffreestanding
+INTERFACE_ASFLAGS += -static -mcmodel=medany
+INTERFACE_LDFLAGS += 
 
 # overwrite ARCH_H defined in $(AM_HOME)/Makefile
 ARCH_H := arch/riscv.h

scripts/riscv32-nemu.mk

@@ -1,9 +1,12 @@
 include $(AM_HOME)/scripts/isa/riscv.mk
 include $(AM_HOME)/scripts/platform/nemu.mk
 AM_CFLAGS  += -DISA_H=\"riscv/riscv.h\" -march=rv32im_zicsr -mabi=ilp32
+AM_ASFLAGS += -march=rv32im_zicsr -mabi=ilp32
 KLIB_CFLAGS += -march=rv32im_zicsr -mabi=ilp32
 AM_LDFLAGS += -melf32lriscv
 INTERFACE_CFLAGS += -march=rv32im_zicsr -mabi=ilp32
+INTERFACE_CXXFLAGS += -march=rv32im_zicsr -mabi=ilp32
+INTERFACE_ASFLAGS += -march=rv32im_zicsr -mabi=ilp32
 
 AM_SRCS += am/src/riscv/nemu/start.S \
            am/src/riscv/nemu/cte.c \

scripts/templates/flags.tmpl

@@ -1,4 +1,10 @@
 "AM_CFLAGS += %s \n\
-AM_LDFLAGS += %s" \
+AM_CXXFLAGS += %s \n\
+AM_INCPATH += %s \n\
+AM_LDFLAGS += %s \n\
+AM_ASFLAGS += %s" \
 "$INTERFACE_CFLAGS" \
-"$INTERFACE_LDFLAGS"
+"$INTERFACE_CXXFLAGS" \
+"$INTERFACE_INCPATH" \
+"$INTERFACE_LDFLAGS" \
+"$INTERFACE_ASFLAGS"