ld: Rewrite lang_size_relro_segment_1

1. Compute the desired PT_GNU_RELRO segment base and find the maximum
section alignment of sections starting from the PT_GNU_RELRO segment.
2. Find the first preceding load section.
3. Don't add the 1-page gap between the first preceding load section and
the relro segment if the maximum page size >= the maximum section
alignment.  Align the PT_GNU_RELRO segment first.  Subtract the maximum
page size if therer is still a 1-page gap.

	PR ld/28743
	PR ld/28819
	* ldlang.c (lang_size_relro_segment_1): Rewrite.
	* testsuite/ld-x86-64/pr28743-1.d: New file.
	* testsuite/ld-x86-64/pr28743-1.s: Likewise.
	* testsuite/ld-x86-64/x86-64.exp: Run pr28743-1.

1 files changed, 50 insertions, 0 deletions

diff --git a/ld/testsuite/ld-x86-64/pr28743-1.d b/ld/testsuite/ld-x86-64/pr28743-1.d
new file mode 100644
index 0000000..4a20f8e
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/pr28743-1.d
@@ -0,0 +1,50 @@
+#as: --64
+#ld: -melf_x86_64 -shared -z relro -z now --hash-style=sysv -z max-page-size=0x1000 -z noseparate-code $NO_DT_RELR_LDFLAGS
+#readelf: -S -l --wide
+#target: x86_64-*-linux*
+
+There are 17 section headers, starting at offset 0x101228:
+
+Section Headers:
+  \[Nr\] Name              Type            Address          Off    Size   ES Flg Lk Inf Al
+  \[ 0\]                   NULL            0000000000000000 000000 000000 00      0   0  0
+  \[ 1\] .hash             HASH            0000000000000120 000120 000018 04   A  2   0  8
+  \[ 2\] .dynsym           DYNSYM          0000000000000138 000138 000048 18   A  3   1  8
+  \[ 3\] .dynstr           STRTAB          0000000000000180 000180 00000a 00   A  0   0  1
+  \[ 4\] .rela.dyn         RELA            0000000000000190 000190 000018 18   A  2   0  8
+  \[ 5\] .plt              PROGBITS        00000000000001b0 0001b0 000010 10  AX  0   0 16
+  \[ 6\] .plt.got          PROGBITS        00000000000001c0 0001c0 000008 08  AX  0   0  8
+  \[ 7\] .text             PROGBITS        00000000000001c8 0001c8 00000c 00  AX  0   0  1
+  \[ 8\] .eh_frame         PROGBITS        00000000000001d8 0001d8 00006c 00   A  0   0  8
+  \[ 9\] .init_array       INIT_ARRAY      00000000000ffff8 0ffff8 000004 08  WA  0   0  8
+  \[10\] .fini_array       FINI_ARRAY      0000000000100000 100000 000100 08  WA  0   0 1048576
+  \[11\] .dynamic          DYNAMIC         0000000000100100 100100 000150 10  WA  3   0  8
+  \[12\] .got              PROGBITS        0000000000100250 100250 000020 08  WA  0   0  8
+  \[13\] .data             PROGBITS        0000000000101000 101000 000100 00  WA  0   0  1
+  \[14\] .symtab           SYMTAB          0000000000000000 101100 000078 18     15   3  8
+  \[15\] .strtab           STRTAB          0000000000000000 101178 000029 00      0   0  1
+  \[16\] .shstrtab         STRTAB          0000000000000000 1011a1 000080 00      0   0  1
+Key to Flags:
+  W \(write\), A \(alloc\), X \(execute\), M \(merge\), S \(strings\), I \(info\),
+  L \(link order\), O \(extra OS processing required\), G \(group\), T \(TLS\),
+  C \(compressed\), x \(unknown\), o \(OS specific\), E \(exclude\),
+  D \(mbind\), l \(large\), p \(processor specific\)
+
+Elf file type is DYN \(Shared object file\)
+Entry point 0x0
+There are 4 program headers, starting at offset 64
+
+Program Headers:
+  Type           Offset   VirtAddr           PhysAddr           FileSiz  MemSiz   Flg Align
+  LOAD           0x000000 0x0000000000000000 0x0000000000000000 0x000244 0x000244 R E 0x1000
+  LOAD           0x0ffff8 0x00000000000ffff8 0x00000000000ffff8 0x001108 0x001108 RW  0x100000
+  DYNAMIC        0x100100 0x0000000000100100 0x0000000000100100 0x000150 0x000150 RW  0x8
+  GNU_RELRO      0x0ffff8 0x00000000000ffff8 0x00000000000ffff8 0x001008 0x001008 R   0x1
+
+ Section to Segment mapping:
+  Segment Sections...
+   00     .hash .dynsym .dynstr .rela.dyn .plt .plt.got .text .eh_frame 
+   01     .init_array .fini_array .dynamic .got .data 
+   02     .dynamic 
+   03     .init_array .fini_array .dynamic .got 
+#pass