From 2eb77f8143f19ae33fd63080afa498991cc225a0 Mon Sep 17 00:00:00 2001
From: Alibek Omarov <a1ba.omarov@gmail.com>
Date: Tue, 8 Dec 2020 01:08:04 +0300
Subject: [PATCH] Add horrible float<>int representation converting utility

---
 util/Makefile        |  10 ++++
 util/float-convert.c | 129 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 139 insertions(+)
 create mode 100644 util/Makefile
 create mode 100644 util/float-convert.c

diff --git a/util/Makefile b/util/Makefile
new file mode 100644
index 0000000..23f2142
--- /dev/null
+++ b/util/Makefile
@@ -0,0 +1,10 @@
+CC ?= cc
+CFLAGS ?= -O3
+
+float-convert:
+	$(CC) $(CFLAGS) float-convert.c -o float-convert
+
+all: float-convert
+
+clean:
+	rm float-convert
diff --git a/util/float-convert.c b/util/float-convert.c
new file mode 100644
index 0000000..72604b6
--- /dev/null
+++ b/util/float-convert.c
@@ -0,0 +1,129 @@
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+// NEVER DO THIS IN REAL-LIFE PROGRAMS
+// UNDEFINED BEHAVIOUR WILL KILL YOUR DOG
+// That's horrible way to convert float to it's integer representation
+// but it works in our particular case
+typedef union
+{
+	double f;
+	uint64_t i;
+} float64;
+
+typedef union
+{
+	float f;
+	uint32_t i;
+} float32;
+
+typedef union
+{
+	long double f;
+	struct {
+		uint64_t lo;
+		uint16_t hi;
+	};
+} float80;
+
+void usage(void)
+{
+	puts("convert <i32|i64|i80|f32|f64|f80> <val> [80bit_hi]");
+	exit(1);
+}
+
+int main(int argc, char **argv)
+{
+	int bits;
+	int float_to_int;
+
+	if(argc < 3) {
+		usage();
+	}
+
+	switch(argv[1][0]) {
+		case 'i':
+			float_to_int = 0;
+			break;
+		case 'f':
+			float_to_int = 1;
+			break;
+		default:
+			usage();
+	}
+
+	bits = atoi(argv[1] + 1);
+	if(bits != 32 && bits != 64 && bits != 80)
+	{
+		usage();
+	}
+
+	if(float_to_int)
+	{
+		switch(bits)
+		{
+		case 32:
+		{
+			float32 f;
+			f.f = strtof(argv[2], 0);
+
+			printf("0x%x", f.i);
+			break;
+		}
+		case 64:
+		{
+			float64 f;
+			f.f = strtod(argv[2], 0);
+
+			printf("0x%lx", f.i);
+			break;
+		}
+		case 80:
+		{
+			float80 f;
+			f.f = strtold(argv[2], 0);
+
+			printf("0x%4x 0x%lx", f.hi, f.lo);
+			break;
+		}
+		}
+	}
+	else
+	{
+		switch(bits)
+		{
+		case 32:
+		{
+			float32 f;
+			f.i = (uint32_t)strtol(argv[2], 0, 0);
+
+			printf("%f", f.f);
+			break;
+		}
+		case 64:
+		{
+			float64 f;
+			f.i = strtoll(argv[2], 0, 0);
+
+			printf("%f", f.f);
+			break;
+		}
+		case 80:
+		{
+			float80 f;
+
+			if (argc < 4) usage();
+
+			f.lo = strtoll(argv[2], 0, 0);
+			f.hi = (uint16_t)strtol(argv[3], 0, 0);
+
+			printf("%Lf", f.f);
+			break;
+		}
+		}
+	}
+
+	puts("");
+	return 0;
+}