Re: [RFC PATCH 09/20] int128: move __uint128_t compiler test to Kconfig
From: Masahiro Yamada <hidden>
Date: 2019-09-30 11:01:42
Also in:
linux-crypto
On Mon, Sep 30, 2019 at 2:41 AM Ard Biesheuvel [off-list ref] wrote:
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 <redacted> Signed-off-by: Ard Biesheuvel <redacted>
Do you still need CONFIG_ARCH_SUPPORTS_INT128 ? I do not know which part in lib/ubsan.c or crypto/ecc.c is arch-dependent...
quoted hunk ↗ jump to hunk
--- arch/arm64/Kconfig | 2 +- arch/riscv/Kconfig | 2 +- arch/x86/Kconfig | 2 +- crypto/ecc.c | 2 +- init/Kconfig | 4 ++++ lib/ubsan.c | 2 +- lib/ubsan.h | 2 +- 7 files changed, 10 insertions(+), 6 deletions(-)diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 3adcec05b1f6..a0f764e2f299 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig@@ -69,7 +69,7 @@ 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_FRAME_POINTERSdiff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 59a4727ecd6c..99be78ac7b33 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig@@ -127,7 +127,7 @@ 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_RECORDdiff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 222855cc0158..97f74a2e1cf3 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig@@ -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_RELAdiff --git a/crypto/ecc.c b/crypto/ecc.c index dfe114bc0c4a..6e6aab6c987c 100644 --- a/crypto/ecc.c +++ b/crypto/ecc.c@@ -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;diff --git a/init/Kconfig b/init/Kconfig index bd7d650d4a99..f5566a985b9e 100644 --- a/init/Kconfig +++ b/init/Kconfig@@ -780,6 +780,10 @@ 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 #diff --git a/lib/ubsan.c b/lib/ubsan.c index e7d31735950d..b652cc14dd60 100644 --- a/lib/ubsan.c +++ b/lib/ubsan.c@@ -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",diff --git a/lib/ubsan.h b/lib/ubsan.h index b8fa83864467..7b56c09473a9 100644 --- a/lib/ubsan.h +++ b/lib/ubsan.h@@ -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 --2.17.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
-- Best Regards Masahiro Yamada _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel