target-supports.exp

用于进行gcc测试

    # Now examine the cache variable.
    if {![info exists profiling_available_saved]} {
	# Some targets don't have any implementation of __bb_init_func or are
	# missing other needed machinery.
	if { [istarget mmix-*-*]
	     || [istarget arm*-*-eabi*]
	     || [istarget arm*-*-elf]
	     || [istarget arm*-*-symbianelf*]
	     || [istarget bfin-*-*]
	     || [istarget powerpc-*-eabi*]
	     || [istarget strongarm*-*-elf]
	     || [istarget xscale*-*-elf]
	     || [istarget cris-*-*]
	     || [istarget crisv32-*-*]
	     || [istarget fido-*-elf]
	     || [istarget h8300-*-*]
	     || [istarget m32c-*-elf]
	     || [istarget m68k-*-elf]
	     || [istarget m68k-*-uclinux*]
	     || [istarget mips*-*-elf*]
	     || [istarget xstormy16-*]
	     || [istarget xtensa-*-elf]
	     || [istarget *-*-vxworks*]
	     || [istarget *-*-windiss] } {
	    set profiling_available_saved 0
	} else {
	    set profiling_available_saved 1
	}
    }

    return $profiling_available_saved
}

# Return 1 if target has packed layout of structure members by
# default, 0 otherwise.  Note that this is slightly different than
# whether the target has "natural alignment": both attributes may be
# false.

proc check_effective_target_default_packed { } {
    return [check_no_compiler_messages default_packed assembly {
	struct x { char a; long b; } c;
	int s[sizeof (c) == sizeof (char) + sizeof (long) ? 1 : -1];
    }]
}

# Return 1 if target has PCC_BITFIELD_TYPE_MATTERS defined.  See
# documentation, where the test also comes from.

proc check_effective_target_pcc_bitfield_type_matters { } {
    # PCC_BITFIELD_TYPE_MATTERS isn't just about unnamed or empty
    # bitfields, but let's stick to the example code from the docs.
    return [check_no_compiler_messages pcc_bitfield_type_matters assembly {
	struct foo1 { char x; char :0; char y; };
	struct foo2 { char x; int :0; char y; };
	int s[sizeof (struct foo1) != sizeof (struct foo2) ? 1 : -1];
    }]
}

# Return 1 if thread local storage (TLS) is supported, 0 otherwise.
#
# This won't change for different subtargets so cache the result.

proc check_effective_target_tls {} {
    return [check_no_compiler_messages tls assembly {
	__thread int i;
	int f (void) { return i; }
	void g (int j) { i = j; }
    }]
}

# Return 1 if *native* thread local storage (TLS) is supported, 0 otherwise.
#
# This won't change for different subtargets so cache the result.

proc check_effective_target_tls_native {} {
    return [check_no_messages_and_pattern tls_native "!emutls" assembly {
	__thread int i;
	int f (void) { return i; }
	void g (int j) { i = j; }
    }]
}

# Return 1 if TLS executables can run correctly, 0 otherwise.
#
# This won't change for different subtargets so cache the result.

proc check_effective_target_tls_runtime {} {
    return [check_runtime tls_runtime {
	__thread int thr = 0;
	int main (void) { return thr; }
    }]
}

# Return 1 if compilation with -fopenmp is error-free for trivial
# code, 0 otherwise.

proc check_effective_target_fopenmp {} {
    return [check_no_compiler_messages fopenmp object {
	void foo (void) { }
    } "-fopenmp"]
}

# Return 1 if compilation with -pthread is error-free for trivial
# code, 0 otherwise.

proc check_effective_target_pthread {} {
    return [check_no_compiler_messages pthread object {
	void foo (void) { }
    } "-pthread"]
}

# Return 1 if the target supports -fstack-protector
proc check_effective_target_fstack_protector {} {
    return [check_runtime fstack_protector {
	int main (void) { return 0; }
    } "-fstack-protector"]
}

# Return 1 if compilation with -freorder-blocks-and-partition is error-free
# for trivial code, 0 otherwise.

proc check_effective_target_freorder {} {
    return [check_no_compiler_messages freorder object {
	void foo (void) { }
    } "-freorder-blocks-and-partition"]
}

# Return 1 if -fpic and -fPIC are supported, as in no warnings or errors
# emitted, 0 otherwise.  Whether a shared library can actually be built is
# out of scope for this test.

proc check_effective_target_fpic { } {
    # Note that M68K has a multilib that supports -fpic but not
    # -fPIC, so we need to check both.  We test with a program that
    # requires GOT references.
    foreach arg {fpic fPIC} {
	if [check_no_compiler_messages $arg object {
	    extern int foo (void); extern int bar;
	    int baz (void) { return foo () + bar; }
	} "-$arg"] {
	    return 1
	}
    }
    return 0
}

# Return true if the target supports -mpaired-single (as used on MIPS).

proc check_effective_target_mpaired_single { } {
    return [check_no_compiler_messages mpaired_single object {
	void foo (void) { }
    } "-mpaired-single"]
}

# Return true if the target has access to FPU instructions.

proc check_effective_target_hard_float { } {
    if { [istarget mips*-*-*] } {
	return [check_no_compiler_messages hard_float assembly {
		#if (defined __mips_soft_float || defined __mips16)
		#error FOO
		#endif
	}]
    }

    # The generic test equates hard_float with "no call for adding doubles".
    return [check_no_messages_and_pattern hard_float "!\\(call" rtl-expand {
	double a (double b, double c) { return b + c; }
    }]
}

# Return true if the target is a 64-bit MIPS target.

proc check_effective_target_mips64 { } {
    return [check_no_compiler_messages mips64 assembly {
	#ifndef __mips64
	#error FOO
	#endif
    }]
}

# Return true if the target is a MIPS target that does not produce
# MIPS16 code.

proc check_effective_target_nomips16 { } {
    return [check_no_compiler_messages nomips16 object {
	#ifndef __mips
	#error FOO
	#else
	/* A cheap way of testing for -mflip-mips16.  */
	void foo (void) { asm ("addiu $20,$20,1"); }
	void bar (void) { asm ("addiu $20,$20,1"); }
	#endif
    }]
}

# Add the options needed for MIPS16 function attributes.  At the moment,
# we don't support MIPS16 PIC.

proc add_options_for_mips16_attribute { flags } {
    return "$flags -mno-abicalls -fno-pic"
}

# Return true if we can force a mode that allows MIPS16 code generation.
# We don't support MIPS16 PIC, and only support MIPS16 -mhard-float
# for o32 and o64.

proc check_effective_target_mips16_attribute { } {
    return [check_no_compiler_messages mips16_attribute assembly {
	#ifdef PIC
	#error FOO
	#endif
	#if defined __mips_hard_float \
	    && (!defined _ABIO32 || _MIPS_SIM != _ABIO32) \
	    && (!defined _ABIO64 || _MIPS_SIM != _ABIO64)
	#error FOO
	#endif
    } [add_options_for_mips16_attribute ""]]
}

# Return 1 if the current multilib does not generate PIC by default.

proc check_effective_target_nonpic { } {
    return [check_no_compiler_messages nonpic assembly {
	#if __PIC__
	#error FOO
	#endif
    }]
}

# Return 1 if the target does not use a status wrapper.

proc check_effective_target_unwrapped { } {
    if { [target_info needs_status_wrapper] != "" \
	     && [target_info needs_status_wrapper] != "0" } {
	return 0
    }
    return 1
}

# Return true if iconv is supported on the target. In particular IBM1047.

proc check_iconv_available { test_what } {
    global libiconv

    # If the tool configuration file has not set libiconv, try "-liconv"
    if { ![info exists libiconv] } {
	set libiconv "-liconv"
    }
    set test_what [lindex $test_what 1]
    return [check_runtime_nocache $test_what [subst {
	#include <iconv.h>
	int main (void)
	{
	  iconv_t cd;

	  cd = iconv_open ("$test_what", "UTF-8");
	  if (cd == (iconv_t) -1)
	    return 1;
	  return 0;
	}
    }] $libiconv]
}

# Return true if named sections are supported on this target.

proc check_named_sections_available { } {
    return [check_no_compiler_messages named_sections assembly {
	int __attribute__ ((section("whatever"))) foo;
    }]
}

# Return 1 if the target supports Fortran real kinds larger than real(8),
# 0 otherwise.
#
# When the target name changes, replace the cached result.

proc check_effective_target_fortran_large_real { } {
    return [check_no_compiler_messages fortran_large_real executable {
	! Fortran
	integer,parameter :: k = selected_real_kind (precision (0.0_8) + 1)
	real(kind=k) :: x
	x = cos (x)
	end
    }]
}

# Return 1 if the target supports Fortran integer kinds larger than
# integer(8), 0 otherwise.
#
# When the target name changes, replace the cached result.

proc check_effective_target_fortran_large_int { } {
    return [check_no_compiler_messages fortran_large_int executable {
	! Fortran
	integer,parameter :: k = selected_int_kind (range (0_8) + 1)
	integer(kind=k) :: i
	end
    }]
}

# Return 1 if we can statically link libgfortran, 0 otherwise.
#
# When the target name changes, replace the cached result.

proc check_effective_target_static_libgfortran { } {
    return [check_no_compiler_messages static_libgfortran executable {
	! Fortran
	print *, 'test'
	end
    } "-static"]
}

# Return 1 if the target supports executing 750CL paired-single instructions, 0
# otherwise.  Cache the result.

proc check_750cl_hw_available { } {
    return [check_cached_effective_target 750cl_hw_available {
	# If this is not the right target then we can skip the test.
	if { ![istarget powerpc-*paired*] } {
	    expr 0
	} else {
	    check_runtime_nocache 750cl_hw_available {
		 int main()
		 {
		 #ifdef __MACH__
		   asm volatile ("ps_mul v0,v0,v0");
		 #else
		   asm volatile ("ps_mul 0,0,0");
		 #endif
		   return 0;
		 }
	    } "-mpaired"
	}
    }]
}

# Return 1 if the target supports executing SSE2 instructions, 0
# otherwise.  Cache the result.

proc check_sse2_hw_available { } {
    return [check_cached_effective_target sse2_hw_available {
	# If this is not the right target then we can skip the test.
	if { !([istarget x86_64-*-*] || [istarget i?86-*-*]) } {
	    expr 0
	} else {
	    check_runtime_nocache sse2_hw_available {
		#include "cpuid.h"
		int main ()
		{
		  unsigned int eax, ebx, ecx, edx = 0;
		  if (__get_cpuid (1, &eax, &ebx, &ecx, &edx))
		    return !(edx & bit_SSE2);
		  return 1;
		}
	    } ""
	}
    }]
}

# Return 1 if the target supports executing AltiVec instructions, 0
# otherwise.  Cache the result.

proc check_vmx_hw_available { } {
    return [check_cached_effective_target vmx_hw_available {
	# Some simulators are known to not support VMX instructions.
	if { [istarget powerpc-*-eabi] || [istarget powerpc*-*-eabispe] } {
	    expr 0
	} else {
	    # Most targets don't require special flags for this test case, but
	    # Darwin does.
	    if { [istarget *-*-darwin*]
		 || [istarget *-*-aix*] } {
		set options "-maltivec"
	    } else {
		set options ""
	    }
	    check_runtime_nocache vmx_hw_available {
		int main()
		{
		#ifdef __MACH__
		  asm volatile ("vor v0,v0,v0");
		#else
		  asm volatile ("vor 0,0,0");
	        #endif
		  return 0;
		}
	    } $options
	}
    }]
}

# GCC 3.4.0 for powerpc64-*-linux* included an ABI fix for passing
# complex float arguments.  This affects gfortran tests that call cabsf
# in libm built by an earlier compiler.  Return 1 if libm uses the same
# argument passing as the compiler under test, 0 otherwise.
#
# When the target name changes, replace the cached result.

proc check_effective_target_broken_cplxf_arg { } {
    return [check_cached_effective_target broken_cplxf_arg {
	# Skip the work for targets known not to be affected.
	if { ![istarget powerpc64-*-linux*] } {
	    expr 0
	} elseif { ![is-effective-target lp64] } {
	    expr 0
	} else {
	    check_runtime_nocache broken_cplxf_arg {
		#include <complex.h>
		extern void abort (void);
		float fabsf (float);
		float cabsf (_Complex float);
		int main ()
		{
		  _Complex float cf;
		  float f;
		  cf = 3 + 4.0fi;
		  f = cabsf (cf);
		  if (fabsf (f - 5.0) > 0.0001)
		    abort ();
		  return 0;
		}
	    } "-lm"
	}
    }]
}