From f24a9f3bf42709fb97b954b6dd6f90853967712e Mon Sep 17 00:00:00 2001 From: Victor Stinner Date: Wed, 15 May 2019 16:31:10 +0200 Subject: bpo-27987: pymalloc: align by 16bytes on 64bit platform (GH-12850) (GH-13319) (cherry picked from commit f0be4bbb9b3cee876249c23f2ae6f38f43fa7495) --- .../next/Core and Builtins/2019-04-16-11-52-21.bpo-27987.n2_DcQ.rst | 3 +++ Objects/obmalloc.c | 6 ++++++ 2 files changed, 9 insertions(+) create mode 100644 Misc/NEWS.d/next/Core and Builtins/2019-04-16-11-52-21.bpo-27987.n2_DcQ.rst diff --git a/Misc/NEWS.d/next/Core and Builtins/2019-04-16-11-52-21.bpo-27987.n2_DcQ.rst b/Misc/NEWS.d/next/Core and Builtins/2019-04-16-11-52-21.bpo-27987.n2_DcQ.rst new file mode 100644 index 0000000..b0f32a5 --- /dev/null +++ b/Misc/NEWS.d/next/Core and Builtins/2019-04-16-11-52-21.bpo-27987.n2_DcQ.rst @@ -0,0 +1,3 @@ +pymalloc returns memory blocks aligned by 16 bytes, instead of 8 bytes, on +64-bit platforms to conform x86-64 ABI. Recent compilers assume this alignment +more often. Patch by Inada Naoki. diff --git a/Objects/obmalloc.c b/Objects/obmalloc.c index 0778c85..2067cf5 100644 --- a/Objects/obmalloc.c +++ b/Objects/obmalloc.c @@ -154,8 +154,14 @@ static int running_on_valgrind = -1; * * You shouldn't change this unless you know what you are doing. */ + +#if SIZEOF_VOID_P > 4 +#define ALIGNMENT 16 /* must be 2^N */ +#define ALIGNMENT_SHIFT 4 +#else #define ALIGNMENT 8 /* must be 2^N */ #define ALIGNMENT_SHIFT 3 +#endif #define ALIGNMENT_MASK (ALIGNMENT - 1) /* Return the number of bytes in size class I, as a uint. */ -- cgit v0.12