diff options
| author |   kettenis <kettenis@openbsd.org> | 2016-12-19 20:03:15 +0000 |
|---|---|---|
| committer | kettenis <kettenis@openbsd.org> | 2016-12-19 20:03:15 +0000 |
| commit | a175244698d03f60581128e7cdf980c34a41905a (patch) | |
| tree | 6bcf0326feed1bd1de44459a6460a6e66ce6ae02 | |
| parent | Revert r1.934 to unbreak autoinstall (diff) | |
| download | wireguard-openbsd-a175244698d03f60581128e7cdf980c34a41905a.tar.xz wireguard-openbsd-a175244698d03f60581128e7cdf980c34a41905a.zip | |
Generating mixed 16-bit/32-bit/64-bit code with clang's integrated
assembler is a bit tricky. It supports the .code16, .code32 and
.code64 directives. But it doesn't know about the data16/data32 and
addr16/addr32 instruction prefixes. Instead it tries to determine
those from the instruction opcode. It mostly succeeds, but there are
a couple of corner cases where clang will generate the "addr32" form
where gas generates the "addr16" form in .code16 segments. That
should be no problem (and just waste a couple of bytes), but it makes
comparing the generated code a bit difficult.
Allow the trampoline code to be compiled with both. For clang #define
away the addr32 prefix and avoid using the data32 prefix by using a
mnemonic that explicitly encodes the size of the operand. Add a few
addr32 prefixes in .code16 blocks to reduce the differences between
code generated by clang and gas.
ok patrick@, deraadt@, mlarkin@
| -rw-r--r-- | sys/arch/amd64/amd64/acpi_wakecode.S | 14 | ||||
| -rw-r--r-- | sys/arch/amd64/amd64/mptramp.S | 8 |
2 files changed, 15 insertions, 7 deletions
diff --git a/sys/arch/amd64/amd64/acpi_wakecode.S b/sys/arch/amd64/amd64/acpi_wakecode.S index 7823861205b..363b34dd7f4 100644 --- a/sys/arch/amd64/amd64/acpi_wakecode.S +++ b/sys/arch/amd64/amd64/acpi_wakecode.S @@ -1,4 +1,4 @@ -/* $OpenBSD: acpi_wakecode.S,v 1.38 2016/05/16 01:19:27 mlarkin Exp $ */ +/* $OpenBSD: acpi_wakecode.S,v 1.39 2016/12/19 20:03:15 kettenis Exp $ */ /* * Copyright (c) 2001 Takanori Watanabe <takawata@jp.freebsd.org> * Copyright (c) 2001 Mitsuru IWASAKI <iwasaki@jp.freebsd.org> @@ -54,6 +54,10 @@ #include <dev/acpi/acpivar.h> #include "lapic.h" +#ifdef __clang__ +#define addr32 +#endif + #define _ACPI_TRMP_LABEL(a) a = . - _C_LABEL(acpi_real_mode_resume) + \ ACPI_TRAMPOLINE #define _ACPI_TRMP_OFFSET(a) a = . - _C_LABEL(acpi_real_mode_resume) @@ -109,7 +113,7 @@ _ACPI_TRMP_OFFSET(acpi_s3_vector_real) movw %ax, %ss movw %cs, %ax movw %ax, %es - lidtl clean_idt + addr32 lidtl clean_idt /* * Set up stack to grow down from offset 0x0FFE. @@ -140,7 +144,7 @@ _ACPI_TRMP_OFFSET(acpi_s3_vector_real) * time, until we restore the saved GDT that we had when we went * to sleep. */ - data32 addr32 lgdt tmp_gdt + addr32 lgdtl tmp_gdt /* * Enable protected mode by setting the PE bit in CR0 @@ -385,7 +389,7 @@ _ACPI_TRMP_OFFSET(hibernate_resume_vector_3) movw %ax, %fs movw %ax, %gs movl $0x0FFE, %esp - lidtl clean_idt + addr32 lidtl clean_idt /* Jump to the S3 resume vector */ ljmp $(_ACPI_RM_CODE_SEG), $acpi_s3_vector_real @@ -422,7 +426,7 @@ _ACPI_TRMP_OFFSET(hibernate_resume_vector_3b) movw %ax, %gs movw %ax, %ss movl $0x0FFE, %esp - lidtl clean_idt + addr32 lidtl clean_idt _ACPI_TRMP_OFFSET(hib_hlt_real) hlt diff --git a/sys/arch/amd64/amd64/mptramp.S b/sys/arch/amd64/amd64/mptramp.S index 0d545ddb3e6..e02eb8cb235 100644 --- a/sys/arch/amd64/amd64/mptramp.S +++ b/sys/arch/amd64/amd64/mptramp.S @@ -1,4 +1,4 @@ -/* $OpenBSD: mptramp.S,v 1.13 2016/05/16 01:54:15 mlarkin Exp $ */ +/* $OpenBSD: mptramp.S,v 1.14 2016/12/19 20:03:15 kettenis Exp $ */ /* $NetBSD: mptramp.S,v 1.1 2003/04/26 18:39:30 fvdl Exp $ */ /*- @@ -84,6 +84,10 @@ #include <machine/mpbiosvar.h> #include <machine/i82489reg.h> +#ifdef __clang__ +#define addr32 +#endif + #define _RELOC(x) ((x) - KERNBASE) #define RELOC(x) _RELOC(_C_LABEL(x)) @@ -114,7 +118,7 @@ _C_LABEL(cpu_spinup_trampoline): movw %cs, %ax movw %ax, %es movw %ax, %ss - data32 addr32 lgdt (mptramp_gdt32_desc) # load flat descriptor table + addr32 lgdtl (mptramp_gdt32_desc) # load flat descriptor table movl %cr0, %eax # get cr0 orl $0x1, %eax # enable protected mode movl %eax, %cr0 # doit |