Ivan Lozano | 074ec48 | 2018-11-21 08:59:37 -0800 | [diff] [blame] | 1 | // Copyright 2018 Google Inc. All rights reserved. |
| 2 | // |
| 3 | // Licensed under the Apache License, Version 2.0 (the "License"); |
| 4 | // you may not use this file except in compliance with the License. |
| 5 | // You may obtain a copy of the License at |
| 6 | // |
| 7 | // http://www.apache.org/licenses/LICENSE-2.0 |
| 8 | // |
| 9 | // Unless required by applicable law or agreed to in writing, software |
| 10 | // distributed under the License is distributed on an "AS IS" BASIS, |
| 11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 12 | // See the License for the specific language governing permissions and |
| 13 | // limitations under the License. |
| 14 | |
| 15 | package cc |
| 16 | |
| 17 | import ( |
| 18 | "android/soong/android" |
| 19 | ) |
| 20 | |
| 21 | type XomProperties struct { |
| 22 | Xom *bool |
| 23 | } |
| 24 | |
| 25 | type xom struct { |
| 26 | Properties XomProperties |
| 27 | } |
| 28 | |
| 29 | func (xom *xom) props() []interface{} { |
| 30 | return []interface{}{&xom.Properties} |
| 31 | } |
| 32 | |
| 33 | func (xom *xom) begin(ctx BaseModuleContext) {} |
| 34 | |
| 35 | func (xom *xom) deps(ctx BaseModuleContext, deps Deps) Deps { |
| 36 | return deps |
| 37 | } |
| 38 | |
| 39 | func (xom *xom) flags(ctx ModuleContext, flags Flags) Flags { |
| 40 | disableXom := false |
| 41 | |
| 42 | if !ctx.Config().EnableXOM() || ctx.Config().XOMDisabledForPath(ctx.ModuleDir()) { |
| 43 | disableXom = true |
| 44 | } |
| 45 | |
| 46 | if xom.Properties.Xom != nil && !*xom.Properties.Xom { |
| 47 | return flags |
| 48 | } |
| 49 | |
| 50 | // If any static dependencies have XOM disabled, we should disable XOM in this module, |
| 51 | // the assumption being if it's been explicitly disabled then there's probably incompatible |
| 52 | // code in the library which may get pulled in. |
Ivan Lozano | 59a7ae9 | 2019-01-31 10:09:13 -0800 | [diff] [blame] | 53 | if !disableXom { |
Ivan Lozano | 074ec48 | 2018-11-21 08:59:37 -0800 | [diff] [blame] | 54 | ctx.VisitDirectDeps(func(m android.Module) { |
| 55 | cc, ok := m.(*Module) |
| 56 | if !ok || cc.xom == nil || !cc.static() { |
| 57 | return |
| 58 | } |
| 59 | if cc.xom.Properties.Xom != nil && !*cc.xom.Properties.Xom { |
| 60 | disableXom = true |
| 61 | return |
| 62 | } |
| 63 | }) |
| 64 | } |
| 65 | |
| 66 | // Enable execute-only if none of the dependencies disable it, |
| 67 | // also if it's explicitly set true (allows overriding dependencies disabling it). |
| 68 | if !disableXom || (xom.Properties.Xom != nil && *xom.Properties.Xom) { |
Ivan Lozano | bd72126 | 2018-11-27 14:33:03 -0800 | [diff] [blame] | 69 | // XOM is only supported on AArch64 when using lld. |
| 70 | if ctx.Arch().ArchType == android.Arm64 && ctx.useClangLld(ctx) { |
Ivan Lozano | 074ec48 | 2018-11-21 08:59:37 -0800 | [diff] [blame] | 71 | flags.LdFlags = append(flags.LdFlags, "-Wl,-execute-only") |
| 72 | } |
| 73 | } |
| 74 | |
| 75 | return flags |
| 76 | } |