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stage2: change max int align from 8 to 16 for more ISAs

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These targets now have a similar disagreement with LLVM about the
alignment of 128-bit integers as x86_64:
 * riscv64
 * powerpc64
 * powerpc64le
 * mips64
 * mips64el
 * sparcv9

See #2987
This commit is contained in:
Andrew Kelley 2022-05-04 19:11:02 -07:00
parent af7e945a7d
commit 0bebb688fb
2 changed files with 21 additions and 21 deletions
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30
lib/std/target.zig
View File

@ -1787,18 +1787,12 @@ pub const Target = struct {
.hexagon,
.mips,
.mipsel,
.mips64,
.mips64el,
.powerpc,
.powerpcle,
.powerpc64,
.powerpc64le,
.r600,
.amdgcn,
.riscv32,
.riscv64,
.sparc,
.sparcv9,
.sparcel,
.s390x,
.lanai,
@ -1812,10 +1806,20 @@ pub const Target = struct {
},
// For x86_64, LLVMABIAlignmentOfType(i128) reports 8. However I think 16
// is a better number because of two reasons:
// is a better number for two reasons:
// 1. Better machine code when loading into SIMD register.
// 2. The C ABI wants 16 for extern structs.
// 3. 16-byte cmpxchg needs 16-byte alignment.
// Same logic for riscv64, powerpc64, mips64, sparcv9.
.x86_64,
.riscv64,
.powerpc64,
.powerpc64le,
.mips64,
.mips64el,
.sparcv9,
// Even LLVMABIAlignmentOfType(i128) agrees on these targets.
.aarch64,
.aarch64_be,
.aarch64_32,
@ -1825,11 +1829,9 @@ pub const Target = struct {
.nvptx64,
=> 16,
// Below this comment are unverified and I have chosen a number
// based on ptrBitWidth.
.spu_2 => 2,
// Below this comment are unverified but based on the fact that C requires
// int128_t to be 16 bytes aligned, it's a safe default.
.spu_2,
.csky,
.arc,
.m68k,
@ -1843,8 +1845,6 @@ pub const Target = struct {
.renderscript32,
.spirv32,
.shave,
=> 4,
.le64,
.amdil64,
.hsail64,
@ -1852,7 +1852,7 @@ pub const Target = struct {
.renderscript64,
.ve,
.spirv64,
=> 8,
=> 16,
};
}
};

12
test/behavior/align.zig
View File

@ -77,18 +77,12 @@ test "alignment and size of structs with 128-bit fields" {
.hexagon,
.mips,
.mipsel,
.mips64,
.mips64el,
.powerpc,
.powerpcle,
.powerpc64,
.powerpc64le,
.r600,
.amdgcn,
.riscv32,
.riscv64,
.sparc,
.sparcv9,
.sparcel,
.s390x,
.lanai,
@ -134,6 +128,12 @@ test "alignment and size of structs with 128-bit fields" {
},
},
.mips64,
.mips64el,
.powerpc64,
.powerpc64le,
.riscv64,
.sparcv9,
.x86_64,
.aarch64,
.aarch64_be,