From b8c5e95e269261a78688770691327a51a1985702 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Krzysztof=20Kosi=C5=84ski?= <krzysio@google.com>
Date: Sat, 7 Sep 2024 00:01:55 +0000
Subject: [PATCH] Add missing pieces of ARMv9.2-A support.

aosp/3255916 didn't add all of the required infrastructure.
Refactor it to be more like x86_64 so it requires less
boilerplate code.

Bug: 364383722
Test: presubmit
Change-Id: Idc5279ffc5fe964bea9f98873c01468944d90091
---
 android/arch_list.go          |  1 +
 cc/config/arm64_device.go     | 30 +++++++-----------------------
 cc/config/arm64_linux_host.go |  4 ++--
 3 files changed, 10 insertions(+), 25 deletions(-)

diff --git a/android/arch_list.go b/android/arch_list.go
index 2937092af..9501c877c 100644
--- a/android/arch_list.go
+++ b/android/arch_list.go
@@ -26,6 +26,7 @@ var archVariants = map[ArchType][]string{
 		"armv8-2a",
 		"armv8-2a-dotprod",
 		"armv9-a",
+		"armv9-2a",
 	},
 	X86: {
 		"amberlake",
diff --git a/cc/config/arm64_device.go b/cc/config/arm64_device.go
index 761afcf18..0dcf2cfd4 100644
--- a/cc/config/arm64_device.go
+++ b/cc/config/arm64_device.go
@@ -118,11 +118,9 @@ func init() {
 
 	pctx.StaticVariable("Arm64Cppflags", strings.Join(arm64Cppflags, " "))
 
-	pctx.StaticVariable("Arm64Armv8ACflags", strings.Join(arm64ArchVariantCflags["armv8-a"], " "))
-	pctx.StaticVariable("Arm64Armv8ABranchProtCflags", strings.Join(arm64ArchVariantCflags["armv8-a-branchprot"], " "))
-	pctx.StaticVariable("Arm64Armv82ACflags", strings.Join(arm64ArchVariantCflags["armv8-2a"], " "))
-	pctx.StaticVariable("Arm64Armv82ADotprodCflags", strings.Join(arm64ArchVariantCflags["armv8-2a-dotprod"], " "))
-	pctx.StaticVariable("Arm64Armv9ACflags", strings.Join(arm64ArchVariantCflags["armv9-a"], " "))
+	for variant, cflags := range arm64ArchVariantCflags {
+		pctx.StaticVariable("Arm64"+variant+"VariantCflags", strings.Join(cflags, " "))
+	}
 
 	pctx.StaticVariable("Arm64CortexA53Cflags", strings.Join(arm64CpuVariantCflags["cortex-a53"], " "))
 	pctx.StaticVariable("Arm64CortexA55Cflags", strings.Join(arm64CpuVariantCflags["cortex-a55"], " "))
@@ -134,14 +132,6 @@ func init() {
 }
 
 var (
-	arm64ArchVariantCflagsVar = map[string]string{
-		"armv8-a":            "${config.Arm64Armv8ACflags}",
-		"armv8-a-branchprot": "${config.Arm64Armv8ABranchProtCflags}",
-		"armv8-2a":           "${config.Arm64Armv82ACflags}",
-		"armv8-2a-dotprod":   "${config.Arm64Armv82ADotprodCflags}",
-		"armv9-a":            "${config.Arm64Armv9ACflags}",
-	}
-
 	arm64CpuVariantCflagsVar = map[string]string{
 		"cortex-a53": "${config.Arm64CortexA53Cflags}",
 		"cortex-a55": "${config.Arm64CortexA55Cflags}",
@@ -211,18 +201,12 @@ func (toolchainArm64) LibclangRuntimeLibraryArch() string {
 }
 
 func arm64ToolchainFactory(arch android.Arch) Toolchain {
-	switch arch.ArchVariant {
-	case "armv8-a":
-	case "armv8-a-branchprot":
-	case "armv8-2a":
-	case "armv8-2a-dotprod":
-	case "armv9-a":
-		// Nothing extra for armv8-a/armv8-2a
-	default:
-		panic(fmt.Sprintf("Unknown ARM architecture version: %q", arch.ArchVariant))
+	// Error now rather than having a confusing Ninja error
+	if _, ok := arm64ArchVariantCflags[arch.ArchVariant]; !ok {
+		panic(fmt.Sprintf("Unknown ARM64 architecture version: %q", arch.ArchVariant))
 	}
 
-	toolchainCflags := []string{arm64ArchVariantCflagsVar[arch.ArchVariant]}
+	toolchainCflags := []string{"${config.Arm64" + arch.ArchVariant + "VariantCflags}"}
 	toolchainCflags = append(toolchainCflags,
 		variantOrDefault(arm64CpuVariantCflagsVar, arch.CpuVariant))
 
diff --git a/cc/config/arm64_linux_host.go b/cc/config/arm64_linux_host.go
index 438e0e6b6..a19b0ed92 100644
--- a/cc/config/arm64_linux_host.go
+++ b/cc/config/arm64_linux_host.go
@@ -87,8 +87,8 @@ func (toolchainLinuxBionicArm64) CrtBeginSharedBinary() []string {
 }
 
 func linuxBionicArm64ToolchainFactory(arch android.Arch) Toolchain {
-	archVariant := "armv8-a" // for host, default to armv8-a
-	toolchainCflags := []string{arm64ArchVariantCflagsVar[archVariant]}
+	// for host, default to armv8-a
+	toolchainCflags := []string{"-march=armv8-a"}
 
 	// We don't specify CPU architecture for host. Conservatively assume
 	// the host CPU needs the fix