From 248082347fc619a7c4381218e01b96ef32545594 Mon Sep 17 00:00:00 2001
From: ccrause <christo.crause@gmail.com>
Date: Fri, 24 Nov 2023 22:05:33 +0200
Subject: [PATCH] AVR optimization LdsMov2Lds
---
compiler/avr/aoptcpu.pas | 89 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 89 insertions(+)
diff --git a/compiler/avr/aoptcpu.pas b/compiler/avr/aoptcpu.pas
index 3ad7b9a40a..0ee8498473 100644
--- a/compiler/avr/aoptcpu.pas
+++ b/compiler/avr/aoptcpu.pas
@@ -401,6 +401,8 @@ Implementation
function TCpuAsmOptimizer.OptPass1LDS(var p : tai) : boolean;
+ var
+ hp1, hp2, hp3, alloc, dealloc: tai;
begin
Result:=false;
if (taicpu(p).oper[1]^.ref^.symbol=nil) and
@@ -424,6 +426,93 @@ Implementation
taicpu(p).loadconst(1,taicpu(p).oper[1]^.ref^.offset-32);
result:=true;
+ end
+
+ { turn
+ alloc reg0
+ alloc reg1
+ lds reg0, label
+ lds reg1, label
+ mov reg2, reg0
+ mov reg3, reg1
+ dealloc reg0
+ dealloc reg1
+
+ into
+ lds reg2, label
+ lds reg3, label
+ }
+ else if not(cs_opt_level3 in current_settings.optimizerswitches) and
+ (taicpu(p).oper[0]^.typ=top_reg) and
+ (GetNextInstruction(p,hp1)) and MatchInstruction(hp1,A_LDS) and
+ (taicpu(hp1).oper[0]^.typ=top_reg) and
+ (GetNextInstruction(hp1, hp2)) and MatchInstruction(hp2,A_MOV) and
+ (taicpu(hp2).oper[1]^.reg=taicpu(p).oper[0]^.reg) and
+ (GetNextInstruction(hp2, hp3)) and MatchInstruction(hp3,A_MOV) and
+ (taicpu(hp3).oper[1]^.reg=taicpu(hp1).oper[0]^.reg) then
+ begin
+ DebugMsg('Peephole LdsLdsMovMov2LdsLds performed', p);
+
+ alloc:=FindRegAllocBackward(taicpu(p).oper[0]^.reg,tai(p.Previous));
+ dealloc:=FindRegDeAlloc(taicpu(p).oper[0]^.reg,tai(hp2.Next));
+ if assigned(alloc) and assigned(dealloc) then
+ begin
+ asml.Remove(alloc);
+ alloc.Free;
+ asml.Remove(dealloc);
+ dealloc.Free;
+ end;
+ taicpu(p).oper[0]^.reg:=taicpu(hp2).oper[0]^.reg;
+ RemoveInstruction(hp2);
+
+ alloc:=FindRegAllocBackward(taicpu(hp1).oper[0]^.reg,tai(hp1.Previous));
+ dealloc:=FindRegDeAlloc(taicpu(hp1).oper[0]^.reg,tai(hp3.Next));
+ if assigned(alloc) and assigned(dealloc) then
+ begin
+ asml.Remove(alloc);
+ alloc.Free;
+ asml.Remove(dealloc);
+ dealloc.Free;
+ end;
+
+ taicpu(hp1).oper[0]^.reg:=taicpu(hp3).oper[0]^.reg;
+ RemoveInstruction(hp3);
+ Result:=true;
+ end
+
+ { turn
+ alloc reg0
+ lds reg0, label
+ ...
+ mov reg1, reg0
+ dealloc reg0
+
+ into
+ lds reg1, label
+ }
+ else if (cs_opt_level3 in current_settings.optimizerswitches) and
+ (taicpu(p).oper[0]^.typ=top_reg) and
+ (GetNextInstructionUsingReg(p,hp1,taicpu(p).oper[0]^.reg)) and
+ MatchInstruction(hp1,A_MOV) and
+ (taicpu(hp1).oper[1]^.reg=taicpu(p).oper[0]^.reg) and
+ (not RegModifiedBetween(taicpu(p).oper[0]^.reg, p, hp1)) and
+ (not RegUsedBetween(taicpu(hp1).oper[0]^.reg, p, hp1)) then
+ begin
+ DebugMsg('Peephole LdsMov2Lds performed', p);
+
+ alloc:=FindRegAllocBackward(taicpu(p).oper[0]^.reg,tai(p.Previous));
+ dealloc:=FindRegDeAlloc(taicpu(p).oper[0]^.reg,tai(hp1.Next));
+ if assigned(alloc) and assigned(dealloc) then
+ begin
+ asml.Remove(alloc);
+ alloc.Free;
+ asml.Remove(dealloc);
+ dealloc.Free;
+ end;
+
+ taicpu(p).oper[0]^.reg:=taicpu(hp1).oper[0]^.reg;
+ RemoveInstruction(hp1);
+ result:=true;
end;
end;