[pypy-commit] pypy arm-backend-2: get rid of the hack to detect the hard float calling convention and use a gcc preprocessor symbol

[bivab]

Author: David Schneider <david.schneider at picle.org>
Branch: arm-backend-2
Changeset: r56383:3d37fbe666b7
Date: 2012-07-21 22:40 +0200
http://bitbucket.org/pypy/pypy/changeset/3d37fbe666b7/

Log:	get rid of the hack to detect the hard float calling convention and
	use a gcc preprocessor symbol

diff --git a/pypy/jit/backend/arm/detect.py b/pypy/jit/backend/arm/detect.py
--- a/pypy/jit/backend/arm/detect.py
+++ b/pypy/jit/backend/arm/detect.py
@@ -3,72 +3,6 @@
 from pypy.rpython.tool import rffi_platform
 from pypy.translator.platform import CompilationError
 
-class Exec(rffi_platform.CConfigEntry):
-    """An entry in a CConfig class that stands for an integer result of a call.
-    """
-    def __init__(self, call):
-        self.call = call
-
-    def prepare_code(self):
-        yield 'long int result = %s;' % (self.call,)
-        yield 'if ((result) <= 0) {'
-        yield '    long long x = (long long)(result);'
-        yield '    printf("value: %lld\\n", x);'
-        yield '} else {'
-        yield '    unsigned long long x = (unsigned long long)(result);'
-        yield '    printf("value: %llu\\n", x);'
-        yield '}'
-
-    def build_result(self, info, config_result):
-        return rffi_platform.expose_value_as_rpython(info['value'])
-
-
-hard_float_check = """
-// HACK HACK HACK 
-// We need to make sure we do not optimize too much of the code
-// below we need that check is called in the original version without constant
-// propagation or anything that could affect the order and number of the
-// arguments passed to it
-// For the same reason we call pypy__arm_hard_float_check using a function
-// pointer instead of calling it directly
-
-int pypy__arm_hard_float_check(int a, float b, int c) __attribute__((optimize("O0")));
-long int pypy__arm_is_hf(void) __attribute__((optimize("O0")));
-
-int pypy__arm_hard_float_check(int a, float b, int c)
-{
-    int reg_value;
-    // get the value that is in the second GPR when we enter the call
-    asm volatile("mov    %[result], r1"
-    : [result]"=l" (reg_value) : : );
-    assert(a == 1);
-    assert(b == 2.0);
-    assert(c == 3);
-    /* if reg_value is 3, then we are using hard
-    floats, because the third argument to this call was stored in the
-    second core register;*/
-    return reg_value == 3;
-}
-
-long int pypy__arm_is_hf(void)
-{
-    int (*f)(int, float, int);
-    // trash argument registers, just in case
-    asm volatile("movw r0, #65535\\n\\t"
-    "movw r1, #65535\\n\\t"
-    "movw r2, #65535\\n\\t");
-    f = &pypy__arm_hard_float_check;
-    return f(1, 2.0, 3);
-}
-        """
-class CConfig:
-    _compilation_info_ = ExternalCompilationInfo(
-        includes=['assert.h'],
-        post_include_bits=[hard_float_check])
-
-    hard_float = Exec('pypy__arm_is_hf()')
-
-
 eci = ExternalCompilationInfo(
     post_include_bits=["""
 // we need to disable optimizations so the compiler does not remove this
@@ -79,10 +13,11 @@
 }
     """])
 
-hard_float = rffi_platform.configure(CConfig)['hard_float']
-
 def detect_hardfloat():
-    return hard_float
+    # http://gcc.gnu.org/ml/gcc-patches/2010-10/msg02419.html
+    if rffi_platform.getdefined('__ARM_PCS_VFP', ''):
+       return rffi_platform.getconstantinteger('__ARM_PCS_VFP', '')
+    return False
 
 def detect_float():
     """Check for hardware float support