math: move x87-family lrint functions to C with inline asm

src/math/i386/llrint.c

+#include <math.h>
+
+long long llrint(double x)
+{
+	long long r;
+	__asm__ ("fistpll %0" : "=m"(r) : "t"(x) : "st");
+	return r;
+}

src/math/i386/llrint.s

-.global llrint
-.type llrint,@function
-llrint:
-	fldl 4(%esp)
-	fistpll 4(%esp)
-	mov 4(%esp),%eax
-	mov 8(%esp),%edx
-	ret

src/math/i386/llrintf.c

+#include <math.h>
+
+long long llrintf(float x)
+{
+	long long r;
+	__asm__ ("fistpll %0" : "=m"(r) : "t"(x) : "st");
+	return r;
+}

src/math/i386/llrintf.s

-.global llrintf
-.type llrintf,@function
-llrintf:
-	sub $8,%esp
-	flds 12(%esp)
-	fistpll (%esp)
-	pop %eax
-	pop %edx
-	ret

src/math/i386/llrintl.c

+#include <math.h>
+
+long long llrintl(long double x)
+{
+	long long r;
+	__asm__ ("fistpll %0" : "=m"(r) : "t"(x) : "st");
+	return r;
+}

src/math/i386/llrintl.s

-.global llrintl
-.type llrintl,@function
-llrintl:
-	fldt 4(%esp)
-	fistpll 4(%esp)
-	mov 4(%esp),%eax
-	mov 8(%esp),%edx
-	ret

src/math/i386/lrint.c

+#include <math.h>
+
+long lrint(double x)
+{
+	long r;
+	__asm__ ("fistpl %0" : "=m"(r) : "t"(x) : "st");
+	return r;
+}

src/math/i386/lrint.s

-.global lrint
-.type lrint,@function
-lrint:
-	fldl 4(%esp)
-	fistpl 4(%esp)
-	mov 4(%esp),%eax
-	ret

src/math/i386/lrintf.c

+#include <math.h>
+
+long lrintf(float x)
+{
+	long r;
+	__asm__ ("fistpl %0" : "=m"(r) : "t"(x) : "st");
+	return r;
+}

src/math/i386/lrintf.s

-.global lrintf
-.type lrintf,@function
-lrintf:
-	flds 4(%esp)
-	fistpl 4(%esp)
-	mov 4(%esp),%eax
-	ret

src/math/i386/lrintl.c

+#include <math.h>
+
+long lrintl(long double x)
+{
+	long r;
+	__asm__ ("fistpl %0" : "=m"(r) : "t"(x) : "st");
+	return r;
+}

src/math/i386/lrintl.s

-.global lrintl
-.type lrintl,@function
-lrintl:
-	fldt 4(%esp)
-	fistpl 4(%esp)
-	mov 4(%esp),%eax
-	ret

src/math/x86_64/llrintl.c

+#include <math.h>
+
+long long llrintl(long double x)
+{
+	long long r;
+	__asm__ ("fistpll %0" : "=m"(r) : "t"(x) : "st");
+	return r;
+}

src/math/x86_64/llrintl.s

-.global llrintl
-.type llrintl,@function
-llrintl:
-	fldt 8(%rsp)
-	fistpll 8(%rsp)
-	mov 8(%rsp),%rax
-	ret

src/math/x86_64/lrintl.c

+#include <math.h>
+
+long lrintl(long double x)
+{
+	long r;
+	__asm__ ("fistpll %0" : "=m"(r) : "t"(x) : "st");
+	return r;
+}

src/math/x86_64/lrintl.s

-.global lrintl
-.type lrintl,@function
-lrintl:
-	fldt 8(%rsp)
-	fistpll 8(%rsp)
-	mov 8(%rsp),%rax
-	ret