cmd/internal/obj: switch to one global Aconv

Aconv is the pretty-printer for instruction opcodes like AMOVQ.
There was one for each architecture.
Make the space of A names have a different region for each architecture,
much as we did for the registers, so a single global Aconv function can
do the work. Each architecture registers its region as a slice of names
at a given offset.

The global names like CALL and JMP are now defined only once.

The A values are used for indexing tables, so make it easy to do the
indexing by making the offset maskable.

Remove a bunch of now-duplicated architecture-specific code.

Change-Id: Ib15647b7145a1c089e21e36543691a19e146b60e
Reviewed-on: https://go-review.googlesource.com/6620
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

1 files changed, 24 insertions, 10 deletions

diff --git a/src/cmd/asm/internal/arch/arch.go b/src/cmd/asm/internal/arch/arch.go
index 1ec8e0c12b..79e2f722ac 100644
--- a/src/cmd/asm/internal/arch/arch.go
+++ b/src/cmd/asm/internal/arch/arch.go
@@ -34,8 +34,6 @@ type Arch struct {
 	RegisterNumber func(string, int16) (int16, bool)
 	// Instruction is a jump.
 	IsJump func(word string) bool
-	// Aconv pretty-prints an instruction opcode for this architecture.
-	Aconv func(int) string
 }
 
 // nilRegisterNumber is the register number function for architectures
@@ -96,9 +94,14 @@ func arch386() *Arch {
 	// Prefixes not used on this architecture.
 
 	instructions := make(map[string]int)
-	for i, s := range i386.Anames {
+	for i, s := range obj.Anames {
 		instructions[s] = i
 	}
+	for i, s := range i386.Anames {
+		if i >= obj.A_ARCHSPECIFIC {
+			instructions[s] = i + obj.ABase386
+		}
+	}
 	// Annoying aliases.
 	instructions["JA"] = i386.AJHI
 	instructions["JAE"] = i386.AJCC
@@ -140,7 +143,6 @@ func arch386() *Arch {
 		RegisterPrefix: nil,
 		RegisterNumber: nilRegisterNumber,
 		IsJump:         jump386,
-		Aconv:          i386.Aconv,
 	}
 }
 
@@ -158,9 +160,14 @@ func archAmd64() *Arch {
 	// Register prefix not used on this architecture.
 
 	instructions := make(map[string]int)
-	for i, s := range x86.Anames {
+	for i, s := range obj.Anames {
 		instructions[s] = i
 	}
+	for i, s := range x86.Anames {
+		if i >= obj.A_ARCHSPECIFIC {
+			instructions[s] = i + obj.ABaseAMD64
+		}
+	}
 	// Annoying aliases.
 	instructions["JA"] = x86.AJHI
 	instructions["JAE"] = x86.AJCC
@@ -209,7 +216,6 @@ func archAmd64() *Arch {
 		RegisterPrefix: nil,
 		RegisterNumber: nilRegisterNumber,
 		IsJump:         jump386,
-		Aconv:          x86.Aconv,
 	}
 }
 
@@ -240,9 +246,14 @@ func archArm() *Arch {
 	}
 
 	instructions := make(map[string]int)
-	for i, s := range arm.Anames {
+	for i, s := range obj.Anames {
 		instructions[s] = i
 	}
+	for i, s := range arm.Anames {
+		if i >= obj.A_ARCHSPECIFIC {
+			instructions[s] = i + obj.ABaseARM
+		}
+	}
 	// Annoying aliases.
 	instructions["B"] = obj.AJMP
 	instructions["BL"] = obj.ACALL
@@ -254,7 +265,6 @@ func archArm() *Arch {
 		RegisterPrefix: registerPrefix,
 		RegisterNumber: armRegisterNumber,
 		IsJump:         jumpArm,
-		Aconv:          arm.Aconv,
 	}
 }
 
@@ -296,9 +306,14 @@ func archPPC64() *Arch {
 	}
 
 	instructions := make(map[string]int)
-	for i, s := range ppc64.Anames {
+	for i, s := range obj.Anames {
 		instructions[s] = i
 	}
+	for i, s := range ppc64.Anames {
+		if i >= obj.A_ARCHSPECIFIC {
+			instructions[s] = i + obj.ABasePPC64
+		}
+	}
 	// Annoying aliases.
 	instructions["BR"] = ppc64.ABR
 	instructions["BL"] = ppc64.ABL
@@ -311,6 +326,5 @@ func archPPC64() *Arch {
 		RegisterPrefix: registerPrefix,
 		RegisterNumber: ppc64RegisterNumber,
 		IsJump:         jumpPPC64,
-		Aconv:          ppc64.Aconv,
 	}
 }