[lld] f9a4d9a - [ELF] -z separate-*: Use max-page-size instead of common-page-size for text/non-SHF_ALLOC transition and writeTrapInstr
Fangrui Song via llvm-commits
llvm-commits at lists.llvm.org
Sun Nov 28 12:48:03 PST 2021
Author: Fangrui Song
Date: 2021-11-28T12:47:50-08:00
New Revision: f9a4d9aa0309ca353de909a19b648ab34f6c0c68
URL: https://github.com/llvm/llvm-project/commit/f9a4d9aa0309ca353de909a19b648ab34f6c0c68
DIFF: https://github.com/llvm/llvm-project/commit/f9a4d9aa0309ca353de909a19b648ab34f6c0c68.diff
LOG: [ELF] -z separate-*: Use max-page-size instead of common-page-size for text/non-SHF_ALLOC transition and writeTrapInstr
For -z separate-code and -z separate-loadable-segments:
When RW is present, the RX to RW transition is aligned with max-page-size.
When RW is absent, the RX to non-SHF_ALLOC transition should use max-page-size as well.
Added:
Modified:
lld/ELF/Writer.cpp
lld/test/ELF/fill-trap-ppc.s
lld/test/ELF/fill-trap.s
Removed:
################################################################################
diff --git a/lld/ELF/Writer.cpp b/lld/ELF/Writer.cpp
index 1906b2deccf71..dce928319b09c 100644
--- a/lld/ELF/Writer.cpp
+++ b/lld/ELF/Writer.cpp
@@ -2608,7 +2608,7 @@ template <class ELFT> void Writer<ELFT>::assignFileOffsets() {
// following section to avoid loading non-segments parts of the file.
if (config->zSeparate != SeparateSegmentKind::None && lastRX &&
lastRX->lastSec == sec)
- off = alignTo(off, config->commonPageSize);
+ off = alignTo(off, config->maxPageSize);
}
for (OutputSection *sec : outputSections)
if (!(sec->flags & SHF_ALLOC))
@@ -2886,9 +2886,9 @@ template <class ELFT> void Writer<ELFT>::writeTrapInstr() {
for (PhdrEntry *p : part.phdrs)
if (p->p_type == PT_LOAD && (p->p_flags & PF_X))
fillTrap(Out::bufferStart + alignDown(p->firstSec->offset + p->p_filesz,
- config->commonPageSize),
+ config->maxPageSize),
Out::bufferStart + alignTo(p->firstSec->offset + p->p_filesz,
- config->commonPageSize));
+ config->maxPageSize));
// Round up the file size of the last segment to the page boundary iff it is
// an executable segment to ensure that other tools don't accidentally
@@ -2900,7 +2900,7 @@ template <class ELFT> void Writer<ELFT>::writeTrapInstr() {
if (last && (last->p_flags & PF_X))
last->p_memsz = last->p_filesz =
- alignTo(last->p_filesz, config->commonPageSize);
+ alignTo(last->p_filesz, config->maxPageSize);
}
}
diff --git a/lld/test/ELF/fill-trap-ppc.s b/lld/test/ELF/fill-trap-ppc.s
index b7e5fa86ba7ce..42ba6f53d5ee5 100644
--- a/lld/test/ELF/fill-trap-ppc.s
+++ b/lld/test/ELF/fill-trap-ppc.s
@@ -2,29 +2,29 @@
# RUN: llvm-mc -filetype=obj -triple=powerpc64le-linux %s -o %t.o
# RUN: ld.lld %t.o -z separate-code -o %t.ppc64le
-# RUN: llvm-readobj -l %t.ppc64le | FileCheck %s
-# RUN: od -Ax -t x1 -N16 -j0x10ff0 %t.ppc64le | FileCheck %s -check-prefix=LE
+# RUN: llvm-readelf -Sl %t.ppc64le | FileCheck %s
+# RUN: od -Ax -t x1 -N16 -j0x1fff0 %t.ppc64le | FileCheck %s -check-prefix=LE
# RUN: llvm-mc -filetype=obj -triple=powerpc64-linux %s -o %t.o
# RUN: ld.lld %t.o -z separate-code -o %t.ppc64
-# RUN: llvm-readobj -l %t.ppc64 | FileCheck %s
-# RUN: od -Ax -t x1 -N16 -j0x10ff0 %t.ppc64 | FileCheck %s -check-prefix=BE
+# RUN: llvm-readelf -Sl %t.ppc64 | FileCheck %s
+# RUN: od -Ax -t x1 -N16 -j0x1fff0 %t.ppc64 | FileCheck %s -check-prefix=BE
-# CHECK: ProgramHeader {
-# CHECK: Type: PT_LOAD
-# CHECK: Offset: 0x10000{{$}}
-# CHECK-NEXT: VirtualAddress:
-# CHECK-NEXT: PhysicalAddress:
-# CHECK-NEXT: FileSize: 4096
-# CHECK-NEXT: MemSize:
-# CHECK-NEXT: Flags [
-# CHECK-NEXT: PF_R
-# CHECK-NEXT: PF_X
-# CHECK-NEXT: ]
+# CHECK: [Nr] Name Type Address Off Size ES Flg Lk Inf Al
+# CHECK-NEXT: [ 0] NULL 0000000000000000 000000 000000 00 0 0 0
+# CHECK-NEXT: [ 1] .text PROGBITS 0000000010010000 010000 000004 00 AX 0 0 4
+## TODO Remove empty .branch_lt
+# CHECK-NEXT: [ 2] .branch_lt PROGBITS 0000000010020000 020000 000000 00 WA 0 0 8
+# CHECK-NEXT: [ 3] .comment PROGBITS 0000000000000000 020000 000008 01 MS 0 0 1
+
+# CHECK: Type Offset VirtAddr PhysAddr FileSiz MemSiz Flg Align
+# CHECK-NEXT: PHDR 0x000040 0x0000000010000040 0x0000000010000040 0x000118 0x000118 R 0x8
+# CHECK-NEXT: LOAD 0x000000 0x0000000010000000 0x0000000010000000 0x000158 0x000158 R 0x10000
+# CHECK-NEXT: LOAD 0x010000 0x0000000010010000 0x0000000010010000 0x010000 0x010000 R E 0x10000
## Check that executable page is filled with traps at its end.
-# LE: 010ff0 08 00 e0 7f 08 00 e0 7f 08 00 e0 7f 08 00 e0 7f
-# BE: 010ff0 7f e0 00 08 7f e0 00 08 7f e0 00 08 7f e0 00 08
+# LE: 01fff0 08 00 e0 7f 08 00 e0 7f 08 00 e0 7f 08 00 e0 7f
+# BE: 01fff0 7f e0 00 08 7f e0 00 08 7f e0 00 08 7f e0 00 08
.globl _start
_start:
diff --git a/lld/test/ELF/fill-trap.s b/lld/test/ELF/fill-trap.s
index bd26c3f8f8d7d..60276a1cc5af6 100644
--- a/lld/test/ELF/fill-trap.s
+++ b/lld/test/ELF/fill-trap.s
@@ -4,20 +4,22 @@
## -z noseparate-code is the default: text segment is not tail padded.
# RUN: ld.lld %t.o -o %t
# RUN: llvm-readobj -l %t | FileCheck %s --check-prefixes=CHECK,NOPAD
-# RUN: ld.lld %t.o -z noseparate-code -o %t
+# RUN: ld.lld %t.o -z noseparate-code -z common-page-size=512 -o %t
# RUN: llvm-readobj -l %t | FileCheck %s --check-prefixes=CHECK,NOPAD
## -z separate-code pads the tail of text segment with traps.
-# RUN: ld.lld %t.o -z separate-code -o %t
+## Make common-page-size smaller than max-page-size.
+## Check that we use max-page-size instead of common-page-size for padding.
+# RUN: ld.lld %t.o -z separate-code -z common-page-size=512 -o %t
# RUN: llvm-readobj -l %t | FileCheck %s --check-prefixes=CHECK,PAD
# RUN: od -Ax -x -N16 -j0x1ff0 %t | FileCheck %s --check-prefix=FILL
## -z separate-loadable-segments pads all segments, including the text segment.
-# RUN: ld.lld %t.o -z separate-loadable-segments -o %t
+# RUN: ld.lld %t.o -z separate-loadable-segments -z common-page-size=512 -o %t
# RUN: llvm-readobj -l %t | FileCheck %s --check-prefixes=CHECK,PAD
# RUN: od -Ax -x -N16 -j0x1ff0 %t | FileCheck %s --check-prefix=FILL
-# RUN: ld.lld %t.o -z separate-code -z noseparate-code -o %t
+# RUN: ld.lld %t.o -z separate-code -z noseparate-code -z common-page-size=512 -o %t
# RUN: llvm-readobj -l %t | FileCheck %s --check-prefixes=CHECK,NOPAD
# CHECK: ProgramHeader {
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