[codegen] Document and test IntoBytes

benches/as_bytes_dynamic_size.rs

@@ -0,0 +1,9 @@
+use zerocopy::*;
+
+#[path = "formats/coco_dynamic_size.rs"]
+mod format;
+
+#[unsafe(no_mangle)]
+fn bench_as_bytes_dynamic_size(source: &format::CocoPacket) -> &[u8] {
+    source.as_bytes()
+}

benches/as_bytes_dynamic_size.x86-64

@@ -0,0 +1,5 @@
+bench_as_bytes_dynamic_size:
+	mov rax, rdi
+	lea rdx, [2*rsi + 5]
+	and rdx, -2
+	ret

benches/as_bytes_dynamic_size.x86-64.mca

@@ -0,0 +1,47 @@
+Iterations:        100
+Instructions:      400
+Total Cycles:      137
+Total uOps:        400
+
+Dispatch Width:    4
+uOps Per Cycle:    2.92
+IPC:               2.92
+Block RThroughput: 1.0
+
+
+Instruction Info:
+[1]: #uOps
+[2]: Latency
+[3]: RThroughput
+[4]: MayLoad
+[5]: MayStore
+[6]: HasSideEffects (U)
+
+[1]    [2]    [3]    [4]    [5]    [6]    Instructions:
+ 1      1     0.33                        mov	rax, rdi
+ 1      1     0.50                        lea	rdx, [2*rsi + 5]
+ 1      1     0.33                        and	rdx, -2
+ 1      1     1.00                  U     ret
+
+
+Resources:
+[0]   - SBDivider
+[1]   - SBFPDivider
+[2]   - SBPort0
+[3]   - SBPort1
+[4]   - SBPort4
+[5]   - SBPort5
+[6.0] - SBPort23
+[6.1] - SBPort23
+
+
+Resource pressure per iteration:
+[0]    [1]    [2]    [3]    [4]    [5]    [6.0]  [6.1]  
+ -      -     1.33   1.33    -     1.34    -      -     
+
+Resource pressure by instruction:
+[0]    [1]    [2]    [3]    [4]    [5]    [6.0]  [6.1]  Instructions:
+ -      -      -     0.66    -     0.34    -      -     mov	rax, rdi
+ -      -     0.33   0.67    -      -      -      -     lea	rdx, [2*rsi + 5]
+ -      -     1.00    -      -      -      -      -     and	rdx, -2
+ -      -      -      -      -     1.00    -      -     ret

benches/as_bytes_static_size.rs

@@ -0,0 +1,9 @@
+use zerocopy::*;
+
+#[path = "formats/coco_static_size.rs"]
+mod format;
+
+#[unsafe(no_mangle)]
+fn bench_as_bytes_static_size(source: &format::CocoPacket) -> &[u8] {
+    source.as_bytes()
+}

benches/as_bytes_static_size.x86-64

@@ -0,0 +1,4 @@
+bench_as_bytes_static_size:
+	mov rax, rdi
+	mov edx, 6
+	ret

benches/as_bytes_static_size.x86-64.mca

@@ -0,0 +1,45 @@
+Iterations:        100
+Instructions:      300
+Total Cycles:      104
+Total uOps:        300
+
+Dispatch Width:    4
+uOps Per Cycle:    2.88
+IPC:               2.88
+Block RThroughput: 1.0
+
+
+Instruction Info:
+[1]: #uOps
+[2]: Latency
+[3]: RThroughput
+[4]: MayLoad
+[5]: MayStore
+[6]: HasSideEffects (U)
+
+[1]    [2]    [3]    [4]    [5]    [6]    Instructions:
+ 1      1     0.33                        mov	rax, rdi
+ 1      1     0.33                        mov	edx, 6
+ 1      1     1.00                  U     ret
+
+
+Resources:
+[0]   - SBDivider
+[1]   - SBFPDivider
+[2]   - SBPort0
+[3]   - SBPort1
+[4]   - SBPort4
+[5]   - SBPort5
+[6.0] - SBPort23
+[6.1] - SBPort23
+
+
+Resource pressure per iteration:
+[0]    [1]    [2]    [3]    [4]    [5]    [6.0]  [6.1]  
+ -      -     0.99   1.00    -     1.01    -      -     
+
+Resource pressure by instruction:
+[0]    [1]    [2]    [3]    [4]    [5]    [6.0]  [6.1]  Instructions:
+ -      -     0.99    -      -     0.01    -      -     mov	rax, rdi
+ -      -      -     1.00    -      -      -      -     mov	edx, 6
+ -      -      -      -      -     1.00    -      -     ret

benches/formats/coco_dynamic_size.rs

@@ -1,23 +1,27 @@
 use zerocopy_derive::*;
 
 // The only valid value of this type are the bytes `0xC0C0`.
-#[derive(TryFromBytes, KnownLayout, Immutable)]
+#[derive(TryFromBytes, KnownLayout, Immutable, IntoBytes)]
 #[repr(u16)]
 pub enum C0C0 {
     _XC0C0 = 0xC0C0,
 }
 
-#[derive(FromBytes, KnownLayout, Immutable)]
-#[repr(C, align(2))]
-pub struct Packet<Magic> {
-    magic_number: Magic,
-    mug_size: u8,
-    temperature: u8,
-    marshmallows: [[u8; 2]],
+macro_rules! define_packet {
+    ($name: ident, $trait: ident, $leading_field: ty) => {
+        #[derive($trait, KnownLayout, Immutable, IntoBytes)]
+        #[repr(C, align(2))]
+        pub struct $name {
+            magic_number: $leading_field,
+            mug_size: u8,
+            temperature: u8,
+            marshmallows: [[u8; 2]],
+        }
+    };
 }
 
-/// A packet begining with the magic number `0xC0C0`.
-pub type CocoPacket = Packet<C0C0>;
+/// Packet begins with bytes 0xC0C0.
+define_packet!(CocoPacket, TryFromBytes, C0C0);
 
-/// A packet beginning with any two initialized bytes.
-pub type LocoPacket = Packet<[u8; 2]>;
+/// Packet begins with any two bytes.
+define_packet!(LocoPacket, FromBytes, [u8; 2]);

benches/formats/coco_static_size.rs

@@ -1,23 +1,27 @@
 use zerocopy_derive::*;
 
 // The only valid value of this type are the bytes `0xC0C0`.
-#[derive(TryFromBytes, KnownLayout, Immutable)]
+#[derive(TryFromBytes, KnownLayout, Immutable, IntoBytes)]
 #[repr(u16)]
 pub enum C0C0 {
     _XC0C0 = 0xC0C0,
 }
 
-#[derive(FromBytes, KnownLayout, Immutable)]
-#[repr(C, align(2))]
-pub struct Packet<Magic> {
-    magic_number: Magic,
-    mug_size: u8,
-    temperature: u8,
-    marshmallows: [u8; 2],
+macro_rules! define_packet {
+    ($name: ident, $trait: ident, $leading_field: ty) => {
+        #[derive($trait, KnownLayout, Immutable, IntoBytes)]
+        #[repr(C, align(2))]
+        pub struct $name {
+            magic_number: $leading_field,
+            mug_size: u8,
+            temperature: u8,
+            marshmallows: [u8; 2],
+        }
+    };
 }
 
-/// A packet begining with the magic number `0xC0C0`.
-pub type CocoPacket = Packet<C0C0>;
+/// Packet begins with bytes 0xC0C0.
+define_packet!(CocoPacket, TryFromBytes, C0C0);
 
-/// A packet beginning with any two initialized bytes.
-pub type LocoPacket = Packet<[u8; 2]>;
+/// Packet begins with any two bytes.
+define_packet!(LocoPacket, FromBytes, [u8; 2]);

benches/write_to_dynamic_size.rs

@@ -0,0 +1,9 @@
+use zerocopy::*;
+
+#[path = "formats/coco_dynamic_size.rs"]
+mod format;
+
+#[unsafe(no_mangle)]
+fn bench_write_to_dynamic_size(source: &format::CocoPacket, destination: &mut [u8]) -> Option<()> {
+    source.write_to(destination).ok()
+}

benches/write_to_dynamic_size.x86-64

@@ -0,0 +1,21 @@
+bench_write_to_dynamic_size:
+	push r14
+	push rbx
+	push rax
+	mov rbx, rcx
+	lea r14, [2*rsi + 5]
+	and r14, -2
+	cmp rcx, r14
+	jne .LBB5_2
+	mov rax, rdi
+	mov rdi, rdx
+	mov rsi, rax
+	mov rdx, rbx
+	call qword ptr [rip + memcpy@GOTPCREL]
+.LBB5_2:
+	cmp rbx, r14
+	sete al
+	add rsp, 8
+	pop rbx
+	pop r14
+	ret

benches/write_to_dynamic_size.x86-64.mca

@@ -0,0 +1,77 @@
+Iterations:        100
+Instructions:      1900
+Total Cycles:      2890
+Total uOps:        2500
+
+Dispatch Width:    4
+uOps Per Cycle:    0.87
+IPC:               0.66
+Block RThroughput: 6.3
+
+
+Instruction Info:
+[1]: #uOps
+[2]: Latency
+[3]: RThroughput
+[4]: MayLoad
+[5]: MayStore
+[6]: HasSideEffects (U)
+
+[1]    [2]    [3]    [4]    [5]    [6]    Instructions:
+ 2      5     1.00           *            push	r14
+ 2      5     1.00           *            push	rbx
+ 2      5     1.00           *            push	rax
+ 1      1     0.33                        mov	rbx, rcx
+ 1      1     0.50                        lea	r14, [2*rsi + 5]
+ 1      1     0.33                        and	r14, -2
+ 1      1     0.33                        cmp	rcx, r14
+ 1      1     1.00                        jne	.LBB5_2
+ 1      1     0.33                        mov	rax, rdi
+ 1      1     0.33                        mov	rdi, rdx
+ 1      1     0.33                        mov	rsi, rax
+ 1      1     0.33                        mov	rdx, rbx
+ 4      7     1.00    *                   call	qword ptr [rip + memcpy@GOTPCREL]
+ 1      1     0.33                        cmp	rbx, r14
+ 1      1     0.50                        sete	al
+ 1      1     0.33                        add	rsp, 8
+ 1      6     0.50    *                   pop	rbx
+ 1      6     0.50    *                   pop	r14
+ 1      1     1.00                  U     ret
+
+
+Resources:
+[0]   - SBDivider
+[1]   - SBFPDivider
+[2]   - SBPort0
+[3]   - SBPort1
+[4]   - SBPort4
+[5]   - SBPort5
+[6.0] - SBPort23
+[6.1] - SBPort23
+
+
+Resource pressure per iteration:
+[0]    [1]    [2]    [3]    [4]    [5]    [6.0]  [6.1]  
+ -      -     4.66   4.64   4.00   4.70   4.00   3.00   
+
+Resource pressure by instruction:
+[0]    [1]    [2]    [3]    [4]    [5]    [6.0]  [6.1]  Instructions:
+ -      -      -      -     1.00    -      -     1.00   push	r14
+ -      -      -      -     1.00    -     1.00    -     push	rbx
+ -      -      -      -     1.00    -      -     1.00   push	rax
+ -      -     0.02   0.97    -     0.01    -      -     mov	rbx, rcx
+ -      -     0.97   0.03    -      -      -      -     lea	r14, [2*rsi + 5]
+ -      -     0.63   0.35    -     0.02    -      -     and	r14, -2
+ -      -     0.31   0.34    -     0.35    -      -     cmp	rcx, r14
+ -      -      -      -      -     1.00    -      -     jne	.LBB5_2
+ -      -     0.33   0.33    -     0.34    -      -     mov	rax, rdi
+ -      -     0.36   0.31    -     0.33    -      -     mov	rdi, rdx
+ -      -     0.33   0.35    -     0.32    -      -     mov	rsi, rax
+ -      -     0.35   0.63    -     0.02    -      -     mov	rdx, rbx
+ -      -      -      -     1.00   1.00   2.00    -     call	qword ptr [rip + memcpy@GOTPCREL]
+ -      -     0.65   0.35    -      -      -      -     cmp	rbx, r14
+ -      -     0.69    -      -     0.31    -      -     sete	al
+ -      -     0.02   0.98    -      -      -      -     add	rsp, 8
+ -      -      -      -      -      -      -     1.00   pop	rbx
+ -      -      -      -      -      -     1.00    -     pop	r14
+ -      -      -      -      -     1.00    -      -     ret

benches/write_to_prefix_dynamic_size.rs

@@ -0,0 +1,12 @@
+use zerocopy::*;
+
+#[path = "formats/coco_dynamic_size.rs"]
+mod format;
+
+#[unsafe(no_mangle)]
+fn bench_write_to_prefix_dynamic_size(
+    source: &format::CocoPacket,
+    destination: &mut [u8],
+) -> Option<()> {
+    source.write_to_prefix(destination).ok()
+}

benches/write_to_prefix_dynamic_size.x86-64

@@ -0,0 +1,21 @@
+bench_write_to_prefix_dynamic_size:
+	push r14
+	push rbx
+	push rax
+	mov rbx, rcx
+	lea r14, [2*rsi + 5]
+	and r14, -2
+	cmp r14, rcx
+	ja .LBB5_2
+	mov rax, rdi
+	mov rdi, rdx
+	mov rsi, rax
+	mov rdx, r14
+	call qword ptr [rip + memcpy@GOTPCREL]
+.LBB5_2:
+	cmp r14, rbx
+	setbe al
+	add rsp, 8
+	pop rbx
+	pop r14
+	ret