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outcoff: don't drop align= option alone on a section line

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If the section/segment directive *only* contained an align= directive,
it would get lost. Fix that.

Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>
This commit is contained in:
H. Peter Anvin (Intel)
2020-07-10 18:14:09 -07:00
parent bb3156533b
commit baaa5ca441
1 changed files with 39 additions and 29 deletions
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68
output/outcoff.c
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@@ -72,11 +72,11 @@
* (2) Win32 doesn't bother putting any flags in the header flags * (2) Win32 doesn't bother putting any flags in the header flags
* field (at offset 0x12 into the file). * field (at offset 0x12 into the file).
* *
* (3) Win32 uses some extra flags into the section header table: * (3) Win32/64 uses some extra flags into the section header table:
* it defines flags 0x80000000 (writable), 0x40000000 (readable) * it defines flags 0x80000000 (writable), 0x40000000 (readable)
* and 0x20000000 (executable), and uses them in the expected * and 0x20000000 (executable), and uses them in the expected
* combinations. It also defines 0x00100000 through 0x00700000 for * combinations. It also defines 0x00100000 through 0x00f00000 for
* section alignments of 1 through 64 bytes. * section alignments of 1 through 8192 bytes.
* *
* (4) Both standard COFF and Win32 COFF seem to use the DWORD * (4) Both standard COFF and Win32 COFF seem to use the DWORD
* field directly after the section name in the section header * field directly after the section name in the section header
@@ -285,14 +285,22 @@ int coff_make_section(char *name, uint32_t flags)
return coff_nsects - 1; return coff_nsects - 1;
} }
/*
* Convert an alignment value to the corresponding flags.
* An alignment value of 0 means no flags should be set.
*/
static inline uint32_t coff_sectalign_flags(unsigned int align) static inline uint32_t coff_sectalign_flags(unsigned int align)
{ {
return (ilog2_32(align) + 1) << 20; return (alignlog2_32(align) + 1) << 20;
} }
/*
* Get the alignment value from a flags field.
* Returns 0 if no alignment defined.
*/
static inline unsigned int coff_alignment(uint32_t flags) static inline unsigned int coff_alignment(uint32_t flags)
{ {
return 1U << (((flags & IMAGE_SCN_ALIGN_MASK) >> 20) - 1); return (1U << ((flags & IMAGE_SCN_ALIGN_MASK) >> 20)) >> 1;
} }
static int32_t coff_section_names(char *name, int *bits) static int32_t coff_section_names(char *name, int *bits)
@@ -364,10 +372,13 @@ static int32_t coff_section_names(char *name, int *bits)
nasm_nonfatal("argument to `align' is not numeric"); nasm_nonfatal("argument to `align' is not numeric");
else { else {
unsigned int align = atoi(q + 6); unsigned int align = atoi(q + 6);
if (!align || ((align - 1) & align)) { /* Allow align=0 meaning use default */
if (!align) {
align_flags = 0;
} else if (!is_power2(align)) {
nasm_nonfatal("argument to `align' is not a" nasm_nonfatal("argument to `align' is not a"
" power of two"); " power of two");
} else if (align > 8192) { } else if (align > COFF_MAX_ALIGNMENT) {
nasm_nonfatal("maximum alignment in COFF is %d bytes", nasm_nonfatal("maximum alignment in COFF is %d bytes",
COFF_MAX_ALIGNMENT); COFF_MAX_ALIGNMENT);
} else { } else {
@@ -382,30 +393,31 @@ static int32_t coff_section_names(char *name, int *bits)
break; break;
if (i == coff_nsects) { if (i == coff_nsects) {
if (!flags) { if (!flags) {
if (!strcmp(name, ".data")) flags = TEXT_FLAGS;
if (!strcmp(name, ".data")) {
flags = DATA_FLAGS; flags = DATA_FLAGS;
else if (!strcmp(name, ".rdata")) } else if (!strcmp(name, ".rdata")) {
flags = RDATA_FLAGS; flags = RDATA_FLAGS;
else if (!strcmp(name, ".bss")) } else if (!strcmp(name, ".bss")) {
flags = BSS_FLAGS; flags = BSS_FLAGS;
else if (win64 && !strcmp(name, ".pdata")) } else if (win64) {
flags = PDATA_FLAGS; if (!strcmp(name, ".pdata"))
else if (win64 && !strcmp(name, ".xdata")) flags = PDATA_FLAGS;
flags = XDATA_FLAGS; else if (!strcmp(name, ".xdata"))
else flags = XDATA_FLAGS;
flags = TEXT_FLAGS; }
} }
i = coff_make_section(name, flags); i = coff_make_section(name, flags);
if (flags) coff_sects[i]->align_flags = align_flags;
coff_sects[i]->flags = flags; } else {
} else if (flags) { if (flags) {
/* Check if any flags are respecified */ /* Warn if non-alignment flags differ */
if (((flags ^ coff_sects[i]->flags) & ~IMAGE_SCN_ALIGN_MASK) &&
/* Warn if non-alignment flags differ */ coff_sects[i]->pass_last_seen == pass_count()) {
if ((flags ^ coff_sects[i]->flags) & ~IMAGE_SCN_ALIGN_MASK && nasm_warn(WARN_OTHER, "section attributes changed on"
coff_sects[i]->pass_last_seen == pass_count()) { " redeclaration of section `%s'", name);
nasm_warn(WARN_OTHER, "section attributes changed on" }
" redeclaration of section `%s'", name);
} }
/* Check if alignment might be needed */ /* Check if alignment might be needed */
@@ -419,6 +431,7 @@ static int32_t coff_section_names(char *name, int *bits)
if (align_flags > sect_align_flags) { if (align_flags > sect_align_flags) {
coff_sects[i]->align_flags = align_flags; coff_sects[i]->align_flags = align_flags;
} }
/* Check if not already aligned */ /* Check if not already aligned */
/* XXX: other formats don't do this... */ /* XXX: other formats don't do this... */
if (coff_sects[i]->len % align) { if (coff_sects[i]->len % align) {
@@ -428,9 +441,6 @@ static int32_t coff_section_names(char *name, int *bits)
nasm_assert(padding <= sizeof buffer); nasm_assert(padding <= sizeof buffer);
if (pass_final())
nasm_nonfatal("section alignment changed during code generation");
if (coff_sects[i]->flags & IMAGE_SCN_CNT_CODE) { if (coff_sects[i]->flags & IMAGE_SCN_CNT_CODE) {
/* Fill with INT 3 instructions */ /* Fill with INT 3 instructions */
memset(buffer, 0xCC, padding); memset(buffer, 0xCC, padding);