From: Joel Sing <joel@sing.id.au>
Date: Sun, 12 Apr 2020 15:39:45 +0000 (+1000)
Subject: cmd/compile: log large copies on riscv64
X-Git-Tag: go1.15beta1~586
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=fb16f4b82e2f7cb1a44cc6e32adad7ce2b0d0553;p=gostls13.git

cmd/compile: log large copies on riscv64

Log large copies in the riscv64 compiler.

This was missed in 47ade08141b23cfeafed92943e16012d5dc5eb8b, resulting in
the new test added to cmd/compile/internal/logopt failing on riscv64.

Change-Id: I6f763e86f42834148e911d16928f9fbabcfa4290
Reviewed-on: https://go-review.googlesource.com/c/go/+/227804
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
---

diff --git a/src/cmd/compile/internal/ssa/gen/RISCV64.rules b/src/cmd/compile/internal/ssa/gen/RISCV64.rules
index 3d3718b9ae..95aadeb2b8 100644
--- a/src/cmd/compile/internal/ssa/gen/RISCV64.rules
+++ b/src/cmd/compile/internal/ssa/gen/RISCV64.rules
@@ -404,7 +404,7 @@
 (Move [8] dst src mem) -> (MOVDstore dst (MOVDload src mem) mem)
 
 // Generic move uses a loop
-(Move [s] {t} dst src mem) ->
+(Move [s] {t} dst src mem) && (s <= 16 || logLargeCopy(v, s)) ->
 	(LoweredMove [t.(*types.Type).Alignment()]
 		dst
 		src
diff --git a/src/cmd/compile/internal/ssa/rewriteRISCV64.go b/src/cmd/compile/internal/ssa/rewriteRISCV64.go
index 7405f686eb..6a0f7f1c96 100644
--- a/src/cmd/compile/internal/ssa/rewriteRISCV64.go
+++ b/src/cmd/compile/internal/ssa/rewriteRISCV64.go
@@ -1894,6 +1894,7 @@ func rewriteValueRISCV64_OpMove(v *Value) bool {
 		return true
 	}
 	// match: (Move [s] {t} dst src mem)
+	// cond: (s <= 16 || logLargeCopy(v, s))
 	// result: (LoweredMove [t.(*types.Type).Alignment()] dst src (ADDI <src.Type> [s-moveSize(t.(*types.Type).Alignment(), config)] src) mem)
 	for {
 		s := v.AuxInt
@@ -1901,6 +1902,9 @@ func rewriteValueRISCV64_OpMove(v *Value) bool {
 		dst := v_0
 		src := v_1
 		mem := v_2
+		if !(s <= 16 || logLargeCopy(v, s)) {
+			break
+		}
 		v.reset(OpRISCV64LoweredMove)
 		v.AuxInt = t.(*types.Type).Alignment()
 		v0 := b.NewValue0(v.Pos, OpRISCV64ADDI, src.Type)
@@ -1909,6 +1913,7 @@ func rewriteValueRISCV64_OpMove(v *Value) bool {
 		v.AddArg4(dst, src, v0, mem)
 		return true
 	}
+	return false
 }
 func rewriteValueRISCV64_OpMul16(v *Value) bool {
 	v_1 := v.Args[1]