admin/llgo
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

ssa: makeSlice both len/cap be non-nil

Browse Source
This commit is contained in:
visualfc
2024-06-26 06:49:48 +08:00
parent c90703dc13
commit dc4b933000
6 changed files with 30 additions and 33 deletions
Download Patch File Download Diff File Expand all files Collapse all files

27
internal/runtime/z_slice.go
View File

@@ -20,6 +20,7 @@ import (
"unsafe"
"github.com/goplus/llgo/c"
"github.com/goplus/llgo/internal/runtime/math"
)
// -----------------------------------------------------------------------------
@@ -120,32 +121,10 @@ func SliceCopy(dst Slice, data unsafe.Pointer, num int, etSize int) int {
return n
}
const (
// _64bit = 1 on 64-bit systems, 0 on 32-bit systems
_64bit = 1 << (^uintptr(0) >> 63) / 2
heapAddrBits = (_64bit)*48 + (1-_64bit)*(32)
maxAlloc = (1 << heapAddrBits) - (1-_64bit)*1
)
const (
PtrSize = 4 << (^uintptr(0) >> 63)
MaxUintptr = ^uintptr(0)
)
// MulUintptr returns a * b and whether the multiplication overflowed.
// On supported platforms this is an intrinsic lowered by the compiler.
func MulUintptr(a, b uintptr) (uintptr, bool) {
if a|b < 1<<(4*PtrSize) || a == 0 {
return a * b, false
}
overflow := b > MaxUintptr/a
return a * b, overflow
}
func MakeSlice(len, cap int, etSize int) Slice {
mem, overflow := MulUintptr(uintptr(etSize), uintptr(cap))
mem, overflow := math.MulUintptr(uintptr(etSize), uintptr(cap))
if overflow || mem > maxAlloc || len < 0 || len > cap {
mem, overflow := MulUintptr(uintptr(etSize), uintptr(len))
mem, overflow := math.MulUintptr(uintptr(etSize), uintptr(len))
if overflow || mem > maxAlloc || len < 0 {
panicmakeslicelen()
}