From 02d5edc591a806cfc81ac8259bf01b5e3358490b Mon Sep 17 00:00:00 2001
From: Chris Fallin <chris@cfallin.org>
Date: Wed, 18 May 2022 11:48:40 -0700
Subject: [PATCH] Upgrade to regalloc2 0.1.3. (#4157)

* Upgrade to regalloc2 0.1.3.

This pulls in bytecodealliance/regalloc2#49, which slightly improves
codegen in some cases where a safepoint (for reference-typed values)
occurs in the same liverange as a register-constrained use. For
example, in bytecodealliance/wasmtime#3785, an extra move instruction
appeared and a callee-save register was used (necessitating a more
expensive prologue) because of suboptimal splitting heuristics, which
this PR fixes. The updated RA2 heuristics appear to have no measured
downsides in existing benchmarks and improve the manually-observed
codegen issue.

* Update filetests where regalloc2 improvement altered behavior with reftypes.
---
 Cargo.lock                                    |  4 ++--
 cranelift/codegen/Cargo.toml                  |  2 +-
 .../filetests/isa/aarch64/reftypes.clif       | 15 ++++++---------
 .../filetests/isa/s390x/reftypes.clif         | 19 +++++++++----------
 4 files changed, 18 insertions(+), 22 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 45c21157bd..eea976da1b 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2351,9 +2351,9 @@ dependencies = [
 
 [[package]]
 name = "regalloc2"
-version = "0.1.2"
+version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1ec1c2e4f4b879982653d243d9561d9f49004ce15a47e9682ad1f6d53a06aac0"
+checksum = "904196c12c9f55d3aea578613219f493ced8e05b3d0c6a42d11cb4142d8b4879"
 dependencies = [
  "fxhash",
  "log",
diff --git a/cranelift/codegen/Cargo.toml b/cranelift/codegen/Cargo.toml
index d96c54e460..8e6b2d08b9 100644
--- a/cranelift/codegen/Cargo.toml
+++ b/cranelift/codegen/Cargo.toml
@@ -23,7 +23,7 @@ serde = { version = "1.0.94", features = ["derive"], optional = true }
 bincode = { version = "1.2.1", optional = true }
 gimli = { version = "0.26.0", default-features = false, features = ["write"], optional = true }
 smallvec = { version = "1.6.1" }
-regalloc2 = { version = "0.1.2", features = ["checker"] }
+regalloc2 = { version = "0.1.3", features = ["checker"] }
 souper-ir = { version = "2.1.0", optional = true }
 # It is a goal of the cranelift-codegen crate to have minimal external dependencies.
 # Please don't add any unless they are essential to the task of creating binary
diff --git a/cranelift/filetests/filetests/isa/aarch64/reftypes.clif b/cranelift/filetests/filetests/isa/aarch64/reftypes.clif
index cd66dd952c..1348494e31 100644
--- a/cranelift/filetests/filetests/isa/aarch64/reftypes.clif
+++ b/cranelift/filetests/filetests/isa/aarch64/reftypes.clif
@@ -67,28 +67,25 @@ block3(v7: r64, v8: r64):
 ;   mov fp, sp
 ;   sub sp, sp, #32
 ; block0:
-;   mov x4, x1
-;   mov x2, x0
+;   str x1, [sp, #16]
+;   str x0, [sp, #8]
 ;   ldr x3, 8 ; b 12 ; data TestCase { length: 1, ascii: [102, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0] } + 0
-;   str x2, [sp, #8]
-;   str x4, [sp, #16]
 ;   blr x3
-;   ldr x2, [sp, #8]
 ;   mov x9, sp
-;   mov x12, x2
-;   str x12, [x9]
+;   ldr x10, [sp, #8]
+;   str x10, [x9]
 ;   and w7, w0, #1
 ;   cbz x7, label1 ; b label3
 ; block1:
 ;   b label2
 ; block2:
-;   mov x1, x12
+;   mov x1, x10
 ;   ldr x0, [sp, #16]
 ;   b label5
 ; block3:
 ;   b label4
 ; block4:
-;   mov x0, x12
+;   mov x0, x10
 ;   ldr x1, [sp, #16]
 ;   b label5
 ; block5:
diff --git a/cranelift/filetests/filetests/isa/s390x/reftypes.clif b/cranelift/filetests/filetests/isa/s390x/reftypes.clif
index adb8c53f0c..673bed07cc 100644
--- a/cranelift/filetests/filetests/isa/s390x/reftypes.clif
+++ b/cranelift/filetests/filetests/isa/s390x/reftypes.clif
@@ -69,27 +69,26 @@ block3(v7: r64, v8: r64):
 ;   aghi %r15, -184
 ;   virtual_sp_offset_adjust 160
 ; block0:
-;   lgr %r4, %r3
-;   lgr %r3, %r2
+;   stg %r3, 176(%r15)
+;   stg %r2, 168(%r15)
 ;   bras %r1, 12 ; data %f + 0 ; lg %r5, 0(%r1)
-;   stg %r3, 168(%r15)
-;   stg %r4, 176(%r15)
 ;   basr %r14, %r5
-;   lg %r3, 168(%r15)
-;   la %r4, 160(%r15)
-;   stg %r3, 0(%r4)
-;   llcr %r4, %r2
-;   chi %r4, 0
+;   la %r3, 160(%r15)
+;   lg %r4, 168(%r15)
+;   stg %r4, 0(%r3)
+;   llcr %r5, %r2
+;   chi %r5, 0
 ;   jgnlh label1 ; jg label3
 ; block1:
 ;   jg label2
 ; block2:
+;   lgr %r3, %r4
 ;   lg %r2, 176(%r15)
 ;   jg label5
 ; block3:
 ;   jg label4
 ; block4:
-;   lgr %r2, %r3
+;   lgr %r2, %r4
 ;   lg %r3, 176(%r15)
 ;   jg label5
 ; block5: