Richard Sandiford <rdsandif...@googlemail.com> writes:
> -march is "which instructions can I use?" and -mtune is "which
> instructions
> give good performance?". My understanding is that you wanted to disable
> the instructions for mips32r2 etc. so that they can be safely linked
> with loongson3a code, in which case it's an -march rather than an
> -mtune decision.
>
> Admittedly the branch-likely case is a bit of a grey area. It can be
> justified on tuning grounds because it's unlikely that deprecated
> instructions will perform will in general, and the tuning for mips*
> archs is supposed to be an all-round compromise. But disabling half
> the FPRs for single floats can't be justified on tuning grounds.
> That's never going to help performance. :-)
OK.
Updated patch attached. I've opted to check for mips as a prefix to the
architecture name as part of the default option handling.
regards,
Matthew
2014-04-30 Matthew Fortune <matthew.fort...@imgtec.com>
gcc/
* config/mips/mips.c: (mips_option_override) Implement -modd-spreg
and defaults.
* config/mips/mips.h: (TARGET_CPU_CPP_BUILTINS) Add _MIPS_SPFPSET
builtin define. (ISA_HAS_ODD_SPREG) Define. (MIN_FPRS_PER_FMT)
Redefine in terms of TARGET_ODD_SPREG.
* config/mips/mips.opt: Add -modd-spreg option.
* doc/invoke.texi: Document -modd-spreg option.
gcc/testsuite/
* gcc.target/mips/mips.exp: Add -m[no-]odd-spreg. Use
_MIPS_SPFPSET to determine default odd-spreg option. Account for
-modd-spreg in minimum arch code.
* gcc.target/mips/oddspreg-1.c: New.
* gcc.target/mips/oddspreg-2.c: New.
* gcc.target/mips/oddspreg-3.c: New.
* gcc.target/mips/oddspreg-4.c: New.
* gcc.target/mips/oddspreg-5.c: New.
* gcc.target/mips/oddspreg-6.c: New.
* gcc.target/mips/oddspreg-7.c: New.
---
gcc/config/mips/mips.c | 17 +++++++++++++++++
gcc/config/mips/mips.h | 13 +++++++++++--
gcc/config/mips/mips.opt | 4 ++++
gcc/doc/invoke.texi | 7 +++++++
gcc/testsuite/gcc.target/mips/mips.exp | 16 +++++++++++++++-
gcc/testsuite/gcc.target/mips/oddspreg-1.c | 13 +++++++++++++
gcc/testsuite/gcc.target/mips/oddspreg-2.c | 10 ++++++++++
gcc/testsuite/gcc.target/mips/oddspreg-3.c | 10 ++++++++++
gcc/testsuite/gcc.target/mips/oddspreg-4.c | 10 ++++++++++
gcc/testsuite/gcc.target/mips/oddspreg-5.c | 15 +++++++++++++++
gcc/testsuite/gcc.target/mips/oddspreg-6.c | 15 +++++++++++++++
gcc/testsuite/gcc.target/mips/oddspreg-7.c | 13 +++++++++++++
12 files changed, 140 insertions(+), 3 deletions(-)
create mode 100644 gcc/testsuite/gcc.target/mips/oddspreg-1.c
create mode 100644 gcc/testsuite/gcc.target/mips/oddspreg-2.c
create mode 100644 gcc/testsuite/gcc.target/mips/oddspreg-3.c
create mode 100644 gcc/testsuite/gcc.target/mips/oddspreg-4.c
create mode 100644 gcc/testsuite/gcc.target/mips/oddspreg-5.c
create mode 100644 gcc/testsuite/gcc.target/mips/oddspreg-6.c
create mode 100644 gcc/testsuite/gcc.target/mips/oddspreg-7.c
diff --git a/gcc/config/mips/mips.c b/gcc/config/mips/mips.c
index 45256e9..c855527 100644
--- a/gcc/config/mips/mips.c
+++ b/gcc/config/mips/mips.c
@@ -17120,6 +17120,23 @@ mips_option_override (void)
warning (0, "the %qs architecture does not support madd or msub"
" instructions", mips_arch_info->name);
+ /* If neither -modd-spreg nor -mno-odd-spreg was given on the command
+ line, set MASK_ODD_SPREG bsaed on the target architecture, ABI. */
+ if ((target_flags_explicit & MASK_ODD_SPREG) == 0)
+ {
+ /* Disable TARGET_ODD_SPREG for generic architectures to make them
+ compatible with those implementations which are
+ !ISA_HAS_ODD_SPREG. */
+ if (ISA_HAS_ODD_SPREG
+ && (strncmp (mips_arch_info->name, "mips", 4) != 0))
+ target_flags |= MASK_ODD_SPREG;
+ else
+ target_flags &= ~MASK_ODD_SPREG;
+ }
+ else if (TARGET_ODD_SPREG && !ISA_HAS_ODD_SPREG)
+ warning (0, "the %qs architecture does not support odd single-precision"
+ " registers", mips_arch_info->name);
+
/* The effect of -mabicalls isn't defined for the EABI. */
if (mips_abi == ABI_EABI && TARGET_ABICALLS)
{
diff --git a/gcc/config/mips/mips.h b/gcc/config/mips/mips.h
index b25865b..94dc210 100644
--- a/gcc/config/mips/mips.h
+++ b/gcc/config/mips/mips.h
@@ -491,6 +491,8 @@ struct mips_cpu_info {
builtin_define_with_int_value ("_MIPS_SZPTR", POINTER_SIZE); \
builtin_define_with_int_value ("_MIPS_FPSET", \
32 / MAX_FPRS_PER_FMT); \
+ builtin_define_with_int_value ("_MIPS_SPFPSET", \
+ 32 / MIN_FPRS_PER_FMT); \
\
/* These defines reflect the ABI in use, not whether the \
FPU is directly accessible. */ \
@@ -808,6 +810,14 @@ struct mips_cpu_info {
been generated up to this point. */
#define ISA_HAS_BRANCHLIKELY (!ISA_MIPS1)
+/* ISA has 32 single-precision registers. */
+#define ISA_HAS_ODD_SPREG (((ISA_MIPS32 \
+ || ISA_MIPS32R2 \
+ || ISA_MIPS64 \
+ || ISA_MIPS64R2) \
+ && !TARGET_LOONGSON_3A) \
+ || TARGET_FLOAT64)
+
/* ISA has a three-operand multiplication instruction (usually spelt "mul").
*/
#define ISA_HAS_MUL3 ((TARGET_MIPS3900 \
|| TARGET_MIPS5400 \
@@ -1349,8 +1359,7 @@ struct mips_cpu_info {
/* The number of consecutive floating-point registers needed to store the
smallest format supported by the FPU. */
#define MIN_FPRS_PER_FMT \
- (ISA_MIPS32 || ISA_MIPS32R2 || ISA_MIPS64 || ISA_MIPS64R2 \
- ? 1 : MAX_FPRS_PER_FMT)
+ (TARGET_ODD_SPREG ? 1 : MAX_FPRS_PER_FMT)
/* The largest size of value that can be held in floating-point
registers and moved with a single instruction. */
diff --git a/gcc/config/mips/mips.opt b/gcc/config/mips/mips.opt
index 6ee5398..f91ca44 100644
--- a/gcc/config/mips/mips.opt
+++ b/gcc/config/mips/mips.opt
@@ -400,5 +400,9 @@ mxgot
Target Report Var(TARGET_XGOT)
Lift restrictions on GOT size
+modd-spreg
+Target Report Mask(ODD_SPREG)
+Enable use of odd-numbered single-precision registers
+
noasmopt
Driver
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index ff43f26..9e89bac 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -776,6 +776,7 @@ Objective-C and Objective-C++ Dialects}.
-mshared -mno-shared -mplt -mno-plt -mxgot -mno-xgot @gol
-mgp32 -mgp64 -mfp32 -mfp64 -mhard-float -msoft-float @gol
-mno-float -msingle-float -mdouble-float @gol
+-modd-spreg -mno-odd-spreg @gol
-mabs=@var{mode} -mnan=@var{encoding} @gol
-mdsp -mno-dsp -mdspr2 -mno-dspr2 @gol
-mmcu -mmno-mcu @gol
@@ -17355,6 +17356,12 @@ operations.
Assume that the floating-point coprocessor supports double-precision
operations. This is the default.
+@item -modd-spreg
+@opindex modd-spreg
+Enable the use of odd-numbered single-precision floating-point registers
+with @option{-mfp32}. This is the default for specific processors
+that are known to support these registers.
+
@item -mabs=2008
@itemx -mabs=legacy
@opindex mabs=2008
diff --git a/gcc/testsuite/gcc.target/mips/mips.exp
b/gcc/testsuite/gcc.target/mips/mips.exp
index 8c72cff..1fa7b09 100644
--- a/gcc/testsuite/gcc.target/mips/mips.exp
+++ b/gcc/testsuite/gcc.target/mips/mips.exp
@@ -270,6 +270,7 @@ foreach option {
synci
relax-pic-calls
mcount-ra-address
+ odd-spreg
} {
lappend mips_option_groups $option "-m(no-|)$option"
}
@@ -755,6 +756,12 @@ proc mips-dg-init {} {
"-mno-paired-single",
#endif
+ #if _MIPS_SPFPSET == 32
+ "-modd-spreg",
+ #else
+ "-mno-odd-spreg",
+ #endif
+
#if __mips_abicalls
"-mabicalls",
#else
@@ -840,6 +847,8 @@ proc mips-dg-finish {} {
# | |
# -mfp64 -mfp32
# | |
+# -modd-spreg -mno-odd-spreg
+# | |
# -mabs=2008/-mabs=legacy <no option>
# | |
# -mhard-float -msoft-float
@@ -929,6 +938,7 @@ proc mips-dg-options { args } {
mips_option_dependency options "-mips3d" "-mpaired-single"
mips_option_dependency options "-mpaired-single" "-mfp64"
mips_option_dependency options "-mfp64" "-mhard-float"
+ mips_option_dependency options "-mfp64" "-modd-spreg"
mips_option_dependency options "-mabs=2008" "-mhard-float"
mips_option_dependency options "-mabs=legacy" "-mhard-float"
mips_option_dependency options "-mrelax-pic-calls" "-mno-plt"
@@ -1045,10 +1055,13 @@ proc mips-dg-options { args } {
# We need a MIPS32 or MIPS64 ISA for:
#
# - paired-single instructions(*)
+ # - odd numbered single precision registers
#
# (*) Note that we don't support MIPS V at the moment.
} elseif { $isa_rev < 1
- && [mips_have_test_option_p options "-mpaired-single"] } {
+ && ([mips_have_test_option_p options "-mpaired-single"]
+ || ([mips_have_test_option_p options "-modd-spreg"]
+ && ![mips_have_test_option_p options "-mfp64"]))} {
if { $gp_size == 32 } {
mips_make_test_option options "-mips32"
} else {
@@ -1192,6 +1205,7 @@ proc mips-dg-options { args } {
}
if { $isa_rev < 1 } {
mips_make_test_option options "-mno-paired-single"
+ mips_make_test_option options "-mno-odd-spreg"
}
if { $isa_rev < 2 } {
if { $gp_size == 32 } {
diff --git a/gcc/testsuite/gcc.target/mips/oddspreg-1.c
b/gcc/testsuite/gcc.target/mips/oddspreg-1.c
new file mode 100644
index 0000000..a9c6957
--- /dev/null
+++ b/gcc/testsuite/gcc.target/mips/oddspreg-1.c
@@ -0,0 +1,13 @@
+/* Check that we enable odd-numbered single precision registers. */
+/* { dg-options "-mabi=32 -modd-spreg -mhard-float" } */
+
+#if _MIPS_SPFPSET != 32
+#error "Incorrect number of single-precision registers reported"
+#endif
+
+void
+foo ()
+{
+ register float foo asm ("$f1");
+ asm volatile ("" : "=f" (foo));
+}
diff --git a/gcc/testsuite/gcc.target/mips/oddspreg-2.c
b/gcc/testsuite/gcc.target/mips/oddspreg-2.c
new file mode 100644
index 0000000..e2e0a26
--- /dev/null
+++ b/gcc/testsuite/gcc.target/mips/oddspreg-2.c
@@ -0,0 +1,10 @@
+/* Check that we disable odd-numbered single precision registers. */
+/* { dg-skip-if "needs asm output" { *-*-* } { "-fno-fat-lto-objects" } { "" }
} */
+/* { dg-options "-mabi=32 -mno-odd-spreg -mhard-float" } */
+
+void
+foo ()
+{
+ register float foo asm ("$f1"); /* { dg-error "isn't suitable for" } */
+ asm volatile ("" : "=f" (foo));
+}
diff --git a/gcc/testsuite/gcc.target/mips/oddspreg-3.c
b/gcc/testsuite/gcc.target/mips/oddspreg-3.c
new file mode 100644
index 0000000..8a2eb63
--- /dev/null
+++ b/gcc/testsuite/gcc.target/mips/oddspreg-3.c
@@ -0,0 +1,10 @@
+/* Check that we disable odd-numbered single precision registers. */
+/* { dg-skip-if "needs asm output" { *-*-* } { "-fno-fat-lto-objects" } { "" }
} */
+/* { dg-options "-mabi=32 -march=loongson3a -mhard-float" } */
+
+void
+foo ()
+{
+ register float foo asm ("$f1"); /* { dg-error "isn't suitable for" } */
+ asm volatile ("" : "=f" (foo));
+}
diff --git a/gcc/testsuite/gcc.target/mips/oddspreg-4.c
b/gcc/testsuite/gcc.target/mips/oddspreg-4.c
new file mode 100644
index 0000000..1364a26
--- /dev/null
+++ b/gcc/testsuite/gcc.target/mips/oddspreg-4.c
@@ -0,0 +1,10 @@
+/* Check that we disable odd-numbered single precision registers. */
+/* { dg-skip-if "needs asm output" { *-*-* } { "-fno-fat-lto-objects" } { "" }
} */
+/* { dg-options "-mabi=32 -mips32r2 -mhard-float" } */
+
+void
+foo ()
+{
+ register float foo asm ("$f1"); /* { dg-error "isn't suitable for" } */
+ asm volatile ("" : "=f" (foo));
+}
diff --git a/gcc/testsuite/gcc.target/mips/oddspreg-5.c
b/gcc/testsuite/gcc.target/mips/oddspreg-5.c
new file mode 100644
index 0000000..723424a
--- /dev/null
+++ b/gcc/testsuite/gcc.target/mips/oddspreg-5.c
@@ -0,0 +1,15 @@
+/* Check that we disable odd-numbered single precision registers and can
+ still generate code. */
+/* { dg-options "-mabi=32 -mno-odd-spreg -mhard-float" } */
+
+#if _MIPS_SPFPSET != 16
+#error "Incorrect number of single-precision registers reported"
+#endif
+
+float a;
+float
+foo ()
+{
+ float b = a + 1.0f;
+ return b;
+}
diff --git a/gcc/testsuite/gcc.target/mips/oddspreg-6.c
b/gcc/testsuite/gcc.target/mips/oddspreg-6.c
new file mode 100644
index 0000000..2d1b129
--- /dev/null
+++ b/gcc/testsuite/gcc.target/mips/oddspreg-6.c
@@ -0,0 +1,15 @@
+/* Check that we disable odd-numbered single precision registers and can
+ still generate code. */
+/* { dg-options "-mabi=64 -mno-odd-spreg -mhard-float" } */
+
+#if _MIPS_SPFPSET != 32
+#error "Incorrect number of single-precision registers reported"
+#endif
+
+float a;
+float
+foo ()
+{
+ float b = a + 1.0f;
+ return b;
+}
diff --git a/gcc/testsuite/gcc.target/mips/oddspreg-7.c
b/gcc/testsuite/gcc.target/mips/oddspreg-7.c
new file mode 100644
index 0000000..b1e79c1
--- /dev/null
+++ b/gcc/testsuite/gcc.target/mips/oddspreg-7.c
@@ -0,0 +1,13 @@
+/* Check that we enable odd-numbered single precision registers. */
+/* { dg-options "-mabi=32 -march=octeon -mhard-float" } */
+
+#if _MIPS_SPFPSET != 32
+#error "Incorrect number of single-precision registers reported"
+#endif
+
+void
+foo ()
+{
+ register float foo asm ("$f1");
+ asm volatile ("" : "=f" (foo));
+}
--
1.7.1
