From d5bea58bf85522a289194d59dfab00207ffdfb4f Mon Sep 17 00:00:00 2001
From: Anton Gerasimov <anton@advancedtelematic.com>
Date: Fri, 26 Aug 2016 13:51:30 +0200
Subject: [PATCH 2/2] Replace wraps with built-in code to remove dependency on
multilib
---
arch/x86/config.mk | 3 --
arch/x86/lib/gcc.c | 97 +++++++++++++++++++++++++++++++++++++++++++++++-------
2 files changed, 86 insertions(+), 14 deletions(-)
diff --git a/arch/x86/config.mk b/arch/x86/config.mk
index d7addd8..892e0fc 100644
--- a/arch/x86/config.mk
+++ b/arch/x86/config.mk
@@ -21,9 +21,6 @@ PLATFORM_RELFLAGS += -ffunction-sections -fvisibility=hidden
PLATFORM_LDFLAGS += -Bsymbolic -Bsymbolic-functions -m elf_i386
-LDFLAGS_FINAL += --wrap=__divdi3 --wrap=__udivdi3
-LDFLAGS_FINAL += --wrap=__moddi3 --wrap=__umoddi3
-
# This is used in the top-level Makefile which does not include
# PLATFORM_LDFLAGS
LDFLAGS_EFI_PAYLOAD := -Bsymbolic -Bsymbolic-functions -shared --no-undefined
diff --git a/arch/x86/lib/gcc.c b/arch/x86/lib/gcc.c
index 3c70d79..6b47785 100644
--- a/arch/x86/lib/gcc.c
+++ b/arch/x86/lib/gcc.c
@@ -8,22 +8,97 @@
#ifdef __GNUC__
+#include <stdint.h>
+#include <stddef.h>
/*
* GCC's libgcc handling is quite broken. While the libgcc functions
* are always regparm(0) the code that calls them uses whatever the
* compiler call specifies. Therefore we need a wrapper around those
* functions. See gcc bug PR41055 for more information.
*/
-#define WRAP_LIBGCC_CALL(type, name) \
- type __normal_##name(type a, type b) __attribute__((regparm(0))); \
- type __wrap_##name(type a, type b); \
- type __attribute__((no_instrument_function)) \
- __wrap_##name(type a, type b) \
- { return __normal_##name(a, b); }
-
-WRAP_LIBGCC_CALL(long long, __divdi3)
-WRAP_LIBGCC_CALL(unsigned long long, __udivdi3)
-WRAP_LIBGCC_CALL(long long, __moddi3)
-WRAP_LIBGCC_CALL(unsigned long long, __umoddi3)
+uint64_t __udivmoddi4 ( uint64_t num,
+ uint64_t den,
+ uint64_t *rem_p )
+{
+ uint64_t quot = 0, qbit = 1;
+
+ if ( den == 0 ) {
+ return 1/((unsigned)den); /* Intentional divide by zero, without
+ triggering a compiler warning which
+ would abort the build */
+ }
+
+ /* Left-justify denominator and count shift */
+ while ( (int64_t)den >= 0 ) {
+ den <<= 1;
+ qbit <<= 1;
+ }
+
+ while ( qbit ) {
+ if ( den <= num ) {
+ num -= den;
+ quot += qbit;
+ }
+ den >>= 1;
+ qbit >>= 1;
+ }
+
+ if ( rem_p )
+ *rem_p = num;
+
+ return quot;
+}
+
+uint64_t __udivdi3( uint64_t num, uint64_t den )
+{
+ return __udivmoddi4(num, den, NULL);
+}
+
+uint64_t __umoddi3 ( uint64_t num, uint64_t den )
+{
+ uint64_t v;
+
+ (void) __udivmoddi4(num, den, &v);
+ return v;
+}
+
+int64_t __divmoddi4 ( int64_t num,
+ int64_t den,
+ int64_t* rem_p )
+{
+ int minus = 0;
+ int64_t v;
+
+ if ( num < 0 ) {
+ num = -num;
+ minus = 1;
+ }
+ if ( den < 0 ) {
+ den = -den;
+ minus ^= 1;
+ }
+
+ v = __udivmoddi4(num, den, (uint64_t *)rem_p);
+ if ( minus ) {
+ v = -v;
+ if ( rem_p )
+ *rem_p = -(*rem_p);
+ }
+
+ return v;
+}
+
+int64_t __moddi3 (int64_t num, int64_t den)
+{
+ int64_t v;
+
+ (void) __divmoddi4(num, den, &v);
+ return v;
+}
+
+int64_t __divdi3(int64_t num, int64_t den)
+{
+ return __divmoddi4(num, den, NULL);
+}
#endif
--
2.9.2