cmd/compile: fix broken type+offset calc for register args

Includes more enhancements to debugging output.

Updates #44816.

Change-Id: I5b21815cf37ed21e7dec6c06f538090f32260203
Reviewed-on: https://go-review.googlesource.com/c/go/+/299409
Trust: David Chase <drchase@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

1 files changed, 74 insertions, 0 deletions

diff --git a/test/abi/bad_internal_offsets.go b/test/abi/bad_internal_offsets.go
new file mode 100644
index 0000000000..d396c1a60f
--- /dev/null
+++ b/test/abi/bad_internal_offsets.go
@@ -0,0 +1,74 @@
+// compile
+
+//go:build !wasm
+// +build !wasm
+
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package genChecker0
+
+var FailCount int
+
+//go:noinline
+func NoteFailure(fidx int, pkg string, pref string, parmNo int, _ uint64) {
+	FailCount += 1
+	if FailCount > 10 {
+		panic("bad")
+	}
+}
+
+//go:noinline
+func NoteFailureElem(fidx int, pkg string, pref string, parmNo int, elem int, _ uint64) {
+	FailCount += 1
+	if FailCount > 10 {
+		panic("bad")
+	}
+}
+
+type StructF0S0 struct {
+	F0 int16
+	F1 string
+	F2 StructF0S1
+}
+
+type StructF0S1 struct {
+	_ uint16
+}
+
+// 0 returns 3 params
+//go:registerparams
+//go:noinline
+func Test0(p0 uint32, p1 StructF0S0, p2 int32) {
+	// consume some stack space, so as to trigger morestack
+	var pad [256]uint64
+	pad[FailCount]++
+	if p0 == 0 {
+		return
+	}
+	p1f0c := int16(-3096)
+	if p1.F0 != p1f0c {
+		NoteFailureElem(0, "genChecker0", "parm", 1, 0, pad[0])
+		return
+	}
+	p1f1c := "f6ꂅ8ˋ<"
+	if p1.F1 != p1f1c {
+		NoteFailureElem(0, "genChecker0", "parm", 1, 1, pad[0])
+		return
+	}
+	p1f2c := StructF0S1{}
+	if p1.F2 != p1f2c {
+		NoteFailureElem(0, "genChecker0", "parm", 1, 2, pad[0])
+		return
+	}
+	p2f0c := int32(496713155)
+	if p2 != p2f0c {
+		NoteFailureElem(0, "genChecker0", "parm", 2, 0, pad[0])
+		return
+	}
+	// recursive call
+	Test0(p0-1, p1, p2)
+	return
+	// 0 addr-taken params, 0 addr-taken returns
+}