backend can report back float point arithmetic mode

[r24603]

include/libfirm/be.h

@@ -82,6 +82,12 @@ typedef struct backend_params {
 	/** Backend settings for if-conversion. */
 	const ir_settings_if_conv_t *if_conv_info;
 
+	/**
+	 * some backends like x87 can only do arithmetic in a specific float
+	 * mode (but convert to/from other float modes).
+	 */
+	ir_mode *mode_float_arithmetic;
+
 	/** Size of the trampoline code. */
 	unsigned trampoline_size;
 

ir/be/TEMPLATE/bearch_TEMPLATE.c

@@ -553,6 +553,7 @@ static const backend_params *TEMPLATE_get_backend_params(void) {
 		NULL,  /* no creator function */
 		NULL,  /* context for create_intrinsic_fkt */
 		NULL,  /* parameter for if conversion */
+		NULL,  /* float arithmetic mode */
 		0,     /* no trampoline support: size 0 */
 		0,     /* no trampoline support: align 0 */
 		NULL   /* no trampoline support: no trampoline builder */

ir/be/arm/bearch_arm.c

@@ -1123,7 +1123,8 @@ static const backend_params *arm_get_libfirm_params(void) {
 		NULL,  /* will be set later */
 		NULL,  /* but yet no creator function */
 		NULL,  /* context for create_intrinsic_fkt */
-		NULL,  /* will be set below */
+		NULL,  /* ifconv_info will be set below */
+		NULL,  /* float arithmetic mode (TODO) */
 		0,     /* no trampoline support: size 0 */
 		0,     /* no trampoline support: align 0 */
 		NULL   /* no trampoline support: no trampoline builder */

ir/be/bemain.c

@@ -348,6 +348,7 @@ static const backend_params be_params = {
 	NULL, /* but yet no creator function */
 	NULL, /* context for create_intrinsic_fkt */
 	NULL, /* no if conversion settings */
+	NULL, /* no float arithmetic mode */
 	0,    /* no trampoline support: size 0 */
 	0,    /* no trampoline support: align 0 */
 	NULL  /* no trampoline support: no trampoline builder */

ir/be/ia32/bearch_ia32.c

@@ -2349,7 +2349,8 @@ static const backend_params *ia32_get_libfirm_params(void) {
 		NULL,  /* will be set later */
 		ia32_create_intrinsic_fkt,
 		&intrinsic_env,  /* context for ia32_create_intrinsic_fkt */
-		NULL,  /* will be set below */
+		NULL,  /* ifconv info will be set below */
+		NULL,  /* float arithmetic mode, will be set below */
 		12,    /* size of trampoline code */
 		4,     /* alignment of trampoline code */
 		ia32_create_trampoline_fkt,
@@ -2361,8 +2362,9 @@ static const backend_params *ia32_get_libfirm_params(void) {
 	 * is called... */
 	init_asm_constraints();
 
-	p.dep_param    = &ad;
-	p.if_conv_info = &ifconv;
+	p.dep_param             = &ad;
+	p.if_conv_info          = &ifconv;
+	p.mode_float_arithmetic = mode_E;
 	return &p;
 }
 

ir/be/mips/bearch_mips.c

@@ -781,6 +781,7 @@ static const backend_params *mips_get_libfirm_params(void) {
 		NULL,  /* but yet no creator function */
 		NULL,  /* context for create_intrinsic_fkt */
 		NULL,  /* no if conversion settings */
+		NULL,  /* float arithmetic mode (TODO) */
 		0,     /* no trampoline support: size 0 */
 		0,     /* no trampoline support: align 0 */
 		NULL   /* no trampoline support: no trampoline builder */

ir/be/ppc32/bearch_ppc32.c

@@ -824,6 +824,7 @@ static const backend_params *ppc32_get_libfirm_params(void) {
 		NULL,  /* but yet no creator function */
 		NULL,  /* context for create_intrinsic_fkt */
 		NULL,  /* no if conversion settings */
+		NULL,  /* no float arithmetic mode (TODO) */
 		0,     /* no trampoline support: size 0 */
 		0,     /* no trampoline support: align 0 */
 		NULL   /* no trampoline support: no trampoline builder */