int128: move __uint128_t compiler test to Kconfig

In order to use 128-bit integer arithmetic in C code, the architecture
needs to have declared support for it by setting ARCH_SUPPORTS_INT128,
and it requires a version of the toolchain that supports this at build
time. This is why all existing tests for ARCH_SUPPORTS_INT128 also test
whether __SIZEOF_INT128__ is defined, since this is only the case for
compilers that can support 128-bit integers.

Let's fold this additional test into the Kconfig declaration of
ARCH_SUPPORTS_INT128 so that we can also use the symbol in Makefiles,
e.g., to decide whether a certain object needs to be included in the
first place.

Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Ard Biesheuvel 2019-11-08 13:22:27 +01:00 committed by Herbert Xu
parent a11d055e7a
commit c12d3362a7
7 changed files with 10 additions and 6 deletions

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@ -67,7 +67,7 @@ config ARM64
select ARCH_USE_QUEUED_SPINLOCKS
select ARCH_SUPPORTS_MEMORY_FAILURE
select ARCH_SUPPORTS_ATOMIC_RMW
select ARCH_SUPPORTS_INT128 if GCC_VERSION >= 50000 || CC_IS_CLANG
select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && (GCC_VERSION >= 50000 || CC_IS_CLANG)
select ARCH_SUPPORTS_NUMA_BALANCING
select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT

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@ -164,7 +164,7 @@ config ARCH_RV32I
config ARCH_RV64I
bool "RV64I"
select 64BIT
select ARCH_SUPPORTS_INT128 if GCC_VERSION >= 50000
select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000
select HAVE_FUNCTION_TRACER
select HAVE_FUNCTION_GRAPH_TRACER
select HAVE_FTRACE_MCOUNT_RECORD

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@ -24,7 +24,7 @@ config X86_64
depends on 64BIT
# Options that are inherently 64-bit kernel only:
select ARCH_HAS_GIGANTIC_PAGE
select ARCH_SUPPORTS_INT128
select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
select ARCH_USE_CMPXCHG_LOCKREF
select HAVE_ARCH_SOFT_DIRTY
select MODULES_USE_ELF_RELA

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@ -336,7 +336,7 @@ static u64 vli_usub(u64 *result, const u64 *left, u64 right,
static uint128_t mul_64_64(u64 left, u64 right)
{
uint128_t result;
#if defined(CONFIG_ARCH_SUPPORTS_INT128) && defined(__SIZEOF_INT128__)
#if defined(CONFIG_ARCH_SUPPORTS_INT128)
unsigned __int128 m = (unsigned __int128)left * right;
result.m_low = m;

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@ -785,6 +785,10 @@ config ARCH_SUPPORTS_NUMA_BALANCING
config ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
bool
config CC_HAS_INT128
def_bool y
depends on !$(cc-option,-D__SIZEOF_INT128__=0)
#
# For architectures that know their GCC __int128 support is sound
#

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@ -119,7 +119,7 @@ static void val_to_string(char *str, size_t size, struct type_descriptor *type,
{
if (type_is_int(type)) {
if (type_bit_width(type) == 128) {
#if defined(CONFIG_ARCH_SUPPORTS_INT128) && defined(__SIZEOF_INT128__)
#if defined(CONFIG_ARCH_SUPPORTS_INT128)
u_max val = get_unsigned_val(type, value);
scnprintf(str, size, "0x%08x%08x%08x%08x",

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@ -78,7 +78,7 @@ struct invalid_value_data {
struct type_descriptor *type;
};
#if defined(CONFIG_ARCH_SUPPORTS_INT128) && defined(__SIZEOF_INT128__)
#if defined(CONFIG_ARCH_SUPPORTS_INT128)
typedef __int128 s_max;
typedef unsigned __int128 u_max;
#else