Legalize fcvt_to_sint and fcvt_to_uint for Intel64.

We need to generate traps on NaN and overflow.

cranelift/filetests/wasm/conversions.cton

@@ -22,14 +22,53 @@ ebb0(v0: i32):
     return v1
 }
 
-; function %i32_trunc_s_f32(f32) -> i32
-; function %i32_trunc_u_f32(f32) -> i32
-; function %i32_trunc_s_f64(f64) -> i32
-; function %i32_trunc_u_f64(f64) -> i32
-; function %i64_trunc_s_f32(f32) -> i64
-; function %i64_trunc_u_f32(f32) -> i64
-; function %i64_trunc_s_f64(f64) -> i64
-; function %i64_trunc_u_f64(f64) -> i64
+function %i32_trunc_s_f32(f32) -> i32 {
+ebb0(v0: f32):
+    v1 = fcvt_to_sint.i32 v0
+    return v1
+}
+
+function %i32_trunc_u_f32(f32) -> i32 {
+ebb0(v0: f32):
+    v1 = fcvt_to_uint.i32 v0
+    return v1
+}
+
+function %i32_trunc_s_f64(f64) -> i32 {
+ebb0(v0: f64):
+    v1 = fcvt_to_sint.i32 v0
+    return v1
+}
+
+function %i32_trunc_u_f64(f64) -> i32 {
+ebb0(v0: f64):
+    v1 = fcvt_to_uint.i32 v0
+    return v1
+}
+
+function %i64_trunc_s_f32(f32) -> i64 {
+ebb0(v0: f32):
+    v1 = fcvt_to_sint.i64 v0
+    return v1
+}
+
+function %i64_trunc_u_f32(f32) -> i64 {
+ebb0(v0: f32):
+    v1 = fcvt_to_uint.i64 v0
+    return v1
+}
+
+function %i64_trunc_s_f64(f64) -> i64 {
+ebb0(v0: f64):
+    v1 = fcvt_to_sint.i64 v0
+    return v1
+}
+
+function %i64_trunc_u_f64(f64) -> i64 {
+ebb0(v0: f64):
+    v1 = fcvt_to_uint.i64 v0
+    return v1
+}
 
 function %f32_trunc_f64(f64) -> f32 {
 ebb0(v0: f64):