From cbeddaa621d586a26bbfe57c27a5412e29c5d352 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Markus=20Fr=C3=B6schle?= <mfro@mubf.de>
Date: Tue, 17 Feb 2015 11:12:29 +0000
Subject: [PATCH] added libgcc_helper.S to retarget libgcc calls for 64 bit
 multiplication/division

---
 BaS_gcc/BaS_gcc.files        |  1 +
 BaS_gcc/Makefile             |  8 +++++---
 BaS_gcc/bas.lk.in            |  4 ++--
 BaS_gcc/util/libgcc_helper.S | 26 ++++++++++++++++++++++++++
 BaS_gcc/x86emu/x86emu.c      |  3 +++
 5 files changed, 37 insertions(+), 5 deletions(-)
 create mode 100644 BaS_gcc/util/libgcc_helper.S

diff --git a/BaS_gcc/BaS_gcc.files b/BaS_gcc/BaS_gcc.files
index cc1783c..83305e4 100644
--- a/BaS_gcc/BaS_gcc.files
+++ b/BaS_gcc/BaS_gcc.files
@@ -201,3 +201,4 @@ Makefile
 x86emu/x86biosemu.c
 x86emu/x86emu.c
 x86emu/x86pcibios.c
+util/libgcc_helper.S
diff --git a/BaS_gcc/Makefile b/BaS_gcc/Makefile
index d3ff0c3..25033cc 100644
--- a/BaS_gcc/Makefile
+++ b/BaS_gcc/Makefile
@@ -29,6 +29,7 @@ AR=$(TCPREFIX)ar
 RANLIB=$(TCPREFIX)ranlib
 NATIVECC=gcc
 
+LDLIBS=-L/usr/lib/gcc/m68k-elf/4.9.2/m5475 -lgcc
 INCLUDE=-Iinclude
 CFLAGS=-mcpu=5474 \
         -g \
@@ -140,6 +141,7 @@ CSRCS= \
 ASRCS= \
 	startcf.S \
 	printf_helper.S \
+	libgcc_helper.S \
 	exceptions.S \
 	xhdi_vec.S \
 	pci_wrappers.S
@@ -255,7 +257,7 @@ define EX_TEMPLATE
 $(1)_MAPFILE=$(1)/$$(basename $$(FLASH_EXEC)).map
 $(1)/$$(FLASH_EXEC): $(1)/$(LIBBAS) $(LDCSRC)
 	$(CPP) $(INCLUDE) -DOBJDIR=$(1)/objs -P -DFORMAT_ELF=$(FORMAT_ELF) -D$$(MACHINE) $(LDCSRC) -o $(1)/$$(LDCFILE)
-	$(LD) --oformat $$(FORMAT) -Map $$($(1)_MAPFILE) --cref -T $(1)/$$(LDCFILE) -o $$@
+	$(LD) --oformat $$(FORMAT) -Map $$($(1)_MAPFILE) --cref -T $(1)/$$(LDCFILE) $(LDLIBS) -o $$@
 ifeq ($(COMPILE_ELF),Y)
 	$(OBJCOPY) -O srec $$@ $$(basename $$@).s19
 else
@@ -266,7 +268,7 @@ endif
 $(1)_MAPFILE_RAM=$(1)/$$(basename $$(RAM_EXEC)).map
 $(1)/$$(RAM_EXEC): $(1)/$(LIBBAS) $(LDCSRC)
 	$(CPP) $(INCLUDE) -DCOMPILE_RAM -DOBJDIR=$(1)/objs -P -DFORMAT_ELF=$(FORMAT_ELF) -D$$(MACHINE) $(LDCSRC) -o $(1)/$$(LDRFILE)
-	$(LD) $(LDFLAGS) --oformat $$(FORMAT) -Map $$($(1)_MAPFILE_RAM) --cref -T $(1)/$$(LDRFILE) -o $$@
+	$(LD) $(LDFLAGS) --oformat $$(FORMAT) -Map $$($(1)_MAPFILE_RAM) --cref -T $(1)/$$(LDRFILE) $(LDLIBS) -o $$@
 ifeq ($(COMPILE_ELF),Y)
 	$(OBJCOPY) -O srec $$@ $$(basename $$@).s19
 else
@@ -277,7 +279,7 @@ endif
 $(1)_MAPFILE_BFL=$(1)/$$(basename $$(BASFLASH_EXEC)).map
 $(1)/$$(BASFLASH_EXEC): $(1)/objs/basflash.o $(1)/objs/basflash_start.o $(1)/$(LIBBAS) $(LDCBFL)
 	$(CPP) $(INCLUDE) -P -DOBJDIR=$(1)/objs -DFORMAT_ELF=$(FORMAT_ELF) -D$$(MACHINE) $(LDCBSRC) -o $(1)/$$(LDCBFS)
-	$(LD) --oformat $$(FORMAT) -Map $$($(1)_MAPFILE_BFL) --cref -T $(1)/$$(LDCFILE) -L$(1) -lbas -o $$@
+	$(LD) --oformat $$(FORMAT) -Map $$($(1)_MAPFILE_BFL) --cref -T $(1)/$$(LDCFILE) -L$(1) -lbas $(LDLIBS) -o $$@
 ifeq ($(COMPILE_ELF),Y)
 	$(OBJCOPY) -O srec $$@ $$(basename $$@).s19
 else
diff --git a/BaS_gcc/bas.lk.in b/BaS_gcc/bas.lk.in
index 0ac26a7..42c5467 100644
--- a/BaS_gcc/bas.lk.in
+++ b/BaS_gcc/bas.lk.in
@@ -79,6 +79,7 @@ SECTIONS
                 OBJDIR/s19reader.o(.text)
                 OBJDIR/bas_printf.o(.text)
                 OBJDIR/bas_string.o(.text)
+                OBJDIR/libgcc_helper.o(.text)
                 OBJDIR/printf_helper.o(.text)
                 OBJDIR/cache.o(.text)
                 OBJDIR/dma.o(.text)
@@ -118,6 +119,7 @@ SECTIONS
 #endif /* COMPILE_RAM */
 
 #if (FORMAT_ELF == 1)
+                *(.eh_frame)
                 *(.rodata)
                 *(.rodata.*)
 #endif
@@ -154,8 +156,6 @@ SECTIONS
          * Global memory map
          */
 
-        ___muldi3 = __muldi3;
-
         /* SDRAM Initialization */
         ___SDRAM                = SDRAM_START;
         ___SDRAM_SIZE           = SDRAM_SIZE;
diff --git a/BaS_gcc/util/libgcc_helper.S b/BaS_gcc/util/libgcc_helper.S
new file mode 100644
index 0000000..c67d48a
--- /dev/null
+++ b/BaS_gcc/util/libgcc_helper.S
@@ -0,0 +1,26 @@
+/*
+ * needed for ELF compilation of x86emu which uses 64 bit multiplication and division. This
+ * is implemented in libgcc.a. However, the ELF compiler emits leading underscores and libgcc
+ * is not compiled like that - we must reimplement the symbols.
+ *
+ * FIXME: This is a quirk and should be replaced by BaS' own implementation later
+ */
+		.global		___divdi3
+		.extern		__divdi3
+___divdi3:	jmp		__divdi3
+
+		.global		___muldi3
+		.extern		__muldi3
+___muldi3:	jmp		__muldi3
+
+		.global		___moddi3
+		.extern		__moddi3
+___moddi3:	jmp		__moddi3
+
+		.global		___udivdi3
+		.extern		__udivdi3
+___udivdi3:	jmp		__udivdi3
+
+		.global		___umoddi3
+		.extern		__umoddi3
+___umoddi3:	jmp		__umoddi3
diff --git a/BaS_gcc/x86emu/x86emu.c b/BaS_gcc/x86emu/x86emu.c
index a157b75..740fc90 100644
--- a/BaS_gcc/x86emu/x86emu.c
+++ b/BaS_gcc/x86emu/x86emu.c
@@ -169,6 +169,7 @@ static void	push_long (struct X86EMU *, uint32_t w);
 static uint16_t	pop_word (struct X86EMU *);
 static uint32_t	pop_long (struct X86EMU *);
 
+
 /****************************************************************************
 REMARKS:
 Handles any pending asychronous interrupts.
@@ -7819,6 +7820,8 @@ idiv_word(struct X86EMU *emu, uint16_t s)
 	emu->x86.R_AX = (uint16_t) div;
 	emu->x86.R_DX = (uint16_t) mod;
 }
+
+
 /****************************************************************************
 REMARKS:
 Implements the IDIV instruction and side effects.