targets: change LLVM features to match vanilla Clang

I mistakenly believed the difference was in LLVM version 11.0.0 vs LLVM
11.1.0. However, the difference is in whether we use the Debian version
of Clang.

The Debian version has had lots of patches. I'm not sure which is to
blame, but it could be this one:
https://salsa.debian.org/pkg-llvm-team/llvm-toolchain/-/blob/snapshot/debian/patches/clang-arm-default-vfp3-on-armv7a.patch

builder/builder_test.go

@@ -5,6 +5,7 @@ import (
 	"io/ioutil"
 	"os"
 	"path/filepath"
+	"runtime"
 	"testing"
 
 	"github.com/tinygo-org/tinygo/compileopts"
@@ -60,7 +61,11 @@ func TestClangAttributes(t *testing.T) {
 		{GOOS: "darwin", GOARCH: "arm64"},
 		{GOOS: "windows", GOARCH: "amd64"},
 	} {
-		t.Run("GOOS="+options.GOOS+",GOARCH="+options.GOARCH, func(t *testing.T) {
+		name := "GOOS=" + options.GOOS + ",GOARCH=" + options.GOARCH
+		if options.GOARCH == "arm" {
+			name += ",GOARM=" + options.GOARM
+		}
+		t.Run(name, func(t *testing.T) {
 			testClangAttributes(t, options)
 		})
 	}
@@ -131,12 +136,12 @@ func testClangAttributes(t *testing.T, options *compileopts.Options) {
 		t.Errorf("target has CPU %#v but Clang makes it CPU %#v", config.CPU(), cpu)
 	}
 	if features != config.Features() {
-		if llvm.Version != "11.0.0" {
-			// This needs to be removed once we switch to LLVM 12.
-			// LLVM 11.0.0 uses a different "target-features" string than LLVM
-			// 11.1.0 for Thumb targets. The Xtensa fork is still based on LLVM
-			// 11.0.0, so we need to skip this check on that version.
-			t.Errorf("target has LLVM features %#v but Clang makes it %#v", config.Features(), features)
+		if hasBuiltinTools || runtime.GOOS != "linux" {
+			// Skip this step when using an external Clang invocation on Linux.
+			// The reason is that Debian has patched Clang in a way that
+			// modifies the LLVM features string, changing lots of FPU/float
+			// related flags. We want to test vanilla Clang, not Debian Clang.
+			t.Errorf("target has LLVM features\n\t%#v\nbut Clang makes it\n\t%#v", config.Features(), features)
 		}
 	}
 }

compileopts/target.go

@@ -262,7 +262,7 @@ func defaultTarget(goos, goarch, triple string) (*TargetSpec, error) {
 		case "armv6":
 			spec.Features = "+armv6,+dsp,+fp64,+strict-align,+vfp2,+vfp2sp,-thumb-mode"
 		case "armv7":
-			spec.Features = "+armv7-a,+dsp,+fp64,+vfp2,+vfp2sp,+vfp3d16,+vfp3d16sp,-thumb-mode"
+			spec.Features = "+armv7-a,+d32,+dsp,+fp64,+neon,+vfp2,+vfp2sp,+vfp3,+vfp3d16,+vfp3d16sp,+vfp3sp,-thumb-mode"
 		}
 	case "arm64":
 		spec.CPU = "generic"

targets/cortex-m0.json

@@ -2,5 +2,5 @@
 	"inherits": ["cortex-m"],
 	"llvm-target": "thumbv6m-unknown-unknown-eabi",
 	"cpu": "cortex-m0",
-	"features": "+armv6-m,+soft-float,+strict-align,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp"
+	"features": "+armv6-m,+strict-align,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-dotprod,-dsp,-fp16fml,-fullfp16,-hwdiv,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-ras,-sb,-sha2"
 }

targets/cortex-m0plus.json

@@ -2,5 +2,5 @@
 	"inherits": ["cortex-m"],
 	"llvm-target": "thumbv6m-unknown-unknown-eabi",
 	"cpu": "cortex-m0plus",
-	"features": "+armv6-m,+soft-float,+strict-align,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp"
+	"features": "+armv6-m,+strict-align,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-dotprod,-dsp,-fp16fml,-fullfp16,-hwdiv,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-ras,-sb,-sha2"
 }

targets/cortex-m3.json

@@ -2,5 +2,5 @@
 	"inherits": ["cortex-m"],
 	"llvm-target": "thumbv7m-unknown-unknown-eabi",
 	"cpu": "cortex-m3",
-	"features": "+armv7-m,+hwdiv,+soft-float,+strict-align,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-ras,-sb,-sha2,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp"
+	"features": "+armv7-m,+hwdiv,+strict-align,+thumb-mode,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-dotprod,-dsp,-fp16fml,-fullfp16,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-ras,-sb,-sha2"
 }

targets/gameboy-advance.json

@@ -1,7 +1,7 @@
 {
 	"llvm-target": "armv4t-unknown-unknown-eabi",
 	"cpu": "arm7tdmi",
-	"features": "+armv4t,+soft-float,+strict-align,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-d32,-dotprod,-dsp,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-hwdiv,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-neon,-ras,-sb,-sha2,-thumb-mode,-vfp2,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp",
+	"features": "+armv4t,+strict-align,-aes,-bf16,-cdecp0,-cdecp1,-cdecp2,-cdecp3,-cdecp4,-cdecp5,-cdecp6,-cdecp7,-crc,-crypto,-dotprod,-dsp,-fp16fml,-fullfp16,-hwdiv,-hwdiv-arm,-i8mm,-lob,-mve,-mve.fp,-ras,-sb,-sha2,-thumb-mode",
 	"build-tags": ["gameboyadvance", "arm7tdmi", "baremetal", "linux", "arm"],
 	"goos": "linux",
 	"goarch": "arm",