Adds the options -mcall-ms2sysv-xlogues to i386.opt and i386.c and
documentation to invoke.texi. Using -mcall-ms2sysv-xlogues on SEH
targets is currently unsupported and will result in a sorry (). SEH
targets can be supported, but it would require adding support for
CFA_REG_EXPRESSION to the SEH unwind emit code in
gcc/config/i386/winnt.c -- this is the same for use of aligned SSE MOVs
after a realigned stack pointer.
Signed-off-by: Daniel Santos <daniel.san...@pobox.com>
---
gcc/config/i386/i386.c | 6 +++++-
gcc/config/i386/i386.opt | 4 ++++
gcc/doc/invoke.texi | 13 ++++++++++++-
3 files changed, 21 insertions(+), 2 deletions(-)
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 113f83742c2..521116195cb 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -4508,7 +4508,8 @@ ix86_target_string (HOST_WIDE_INT isa, HOST_WIDE_INT isa2,
{ "-mstv", MASK_STV },
{ "-mavx256-split-unaligned-load", MASK_AVX256_SPLIT_UNALIGNED_LOAD },
{ "-mavx256-split-unaligned-store",
MASK_AVX256_SPLIT_UNALIGNED_STORE },
- { "-mprefer-avx128", MASK_PREFER_AVX128 }
+ { "-mprefer-avx128", MASK_PREFER_AVX128 },
+ { "-mcall-ms2sysv-xlogues", MASK_CALL_MS2SYSV_XLOGUES }
};
/* Additional flag options. */
@@ -6319,6 +6320,9 @@ ix86_option_override_internal (bool main_args_p,
#endif
}
+ if (TARGET_SEH && TARGET_CALL_MS2SYSV_XLOGUES)
+ sorry ("-mcall-ms2sysv-xlogues isn%'t currently supported with SEH");
+
if (!(opts_set->x_target_flags & MASK_VZEROUPPER))
opts->x_target_flags |= MASK_VZEROUPPER;
if (!(opts_set->x_target_flags & MASK_STV))
diff --git a/gcc/config/i386/i386.opt b/gcc/config/i386/i386.opt
index 9384e29b1de..65b228544a5 100644
--- a/gcc/config/i386/i386.opt
+++ b/gcc/config/i386/i386.opt
@@ -538,6 +538,10 @@ Enum(calling_abi) String(sysv) Value(SYSV_ABI)
EnumValue
Enum(calling_abi) String(ms) Value(MS_ABI)
+mcall-ms2sysv-xlogues
+Target Report Mask(CALL_MS2SYSV_XLOGUES) Save
+Use libgcc stubs to save and restore registers clobbered by 64-bit Microsoft
to System V ABI calls.
+
mveclibabi=
Target RejectNegative Joined Var(ix86_veclibabi_type) Enum(ix86_veclibabi)
Init(ix86_veclibabi_type_none)
Vector library ABI to use.
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 0eeea7b3b87..c9e565a9216 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -1209,7 +1209,7 @@ See RS/6000 and PowerPC Options.
-msse2avx -mfentry -mrecord-mcount -mnop-mcount -m8bit-idiv @gol
-mavx256-split-unaligned-load -mavx256-split-unaligned-store @gol
-malign-data=@var{type} -mstack-protector-guard=@var{guard} @gol
--mmitigate-rop -mgeneral-regs-only}
+-mmitigate-rop -mgeneral-regs-only -mcall-ms2sysv-xlogues}
@emph{x86 Windows Options}
@gccoptlist{-mconsole -mcygwin -mno-cygwin -mdll @gol
@@ -25308,6 +25308,17 @@ You can control this behavior for specific functions by
using the function attributes @code{ms_abi} and @code{sysv_abi}.
@xref{Function Attributes}.
+@item -mcall-ms2sysv-xlogues
+@opindex mcall-ms2sysv-xlogues
+@opindex mno-call-ms2sysv-xlogues
+Due to differences in 64-bit ABIs, any Microsoft ABI function that calls a
+System V ABI function must consider RSI, RDI and XMM6-15 as clobbered. By
+default, the code for saving and restoring these registers is emitted inline,
+resulting in fairly lengthy prologues and epilogues. Using
+@option{-mcall-ms2sysv-xlogues} emits prologues and epilogues that
+use stubs in the static portion of libgcc to perform these saves & restores,
+thus reducing function size at the cost of a few extra instructions.
+
@item -mtls-dialect=@var{type}
@opindex mtls-dialect
Generate code to access thread-local storage using the @samp{gnu} or
--
2.11.0
