wazevo(regalloc): fixes the PHI value liverange (#1812)

Signed-off-by: Takeshi Yoneda <t.y.mathetake@gmail.com>

internal/engine/wazevo/backend/backend_test.go

@@ -503,13 +503,13 @@ L4 (SSA Block: blk3):
 L1 (SSA Block: blk0):
 	stp x30, xzr, [sp, #-0x10]!
 	str xzr, [sp, #-0x10]!
-	cbnz w2, #0xc (L2)
+	cbnz w2, #0x8 (L2)
 L3 (SSA Block: blk2):
-	mov x0, x3
 	b #0x8 (L4)
 L2 (SSA Block: blk1):
-	mov x0, x2
+	mov x3, x2
 L4 (SSA Block: blk3):
+	mov x0, x3
 	add sp, sp, #0x10
 	ldr x30, [sp], #0x10
 	ret

internal/engine/wazevo/backend/regalloc/regalloc.go

@@ -219,7 +219,7 @@ func (a *Allocator) livenessAnalysis(f Function) {
 			if instr.IsCopy() {
 				id := int(dstVR.ID())
 				if id < len(a.phiBlocks) && a.phiBlocks[id] != nil {
-					info.liveOuts[srcVR] = struct{}{}
+					info.liveOuts[dstVR] = struct{}{}
 				}
 				a.recordCopyRelation(dstVR, srcVR)
 			}

internal/integration_test/fuzz/wazerolib/nodiff.go

@@ -130,6 +130,9 @@ func requireNoDiff(wasmBin []byte, checkMemory bool, requireNoError func(err err
 
 func ensureMutableGlobalsMatch(compilerMod, interpreterMod api.Module, requireNoError func(err error)) {
 	ci, ii := compilerMod.(*wasm.ModuleInstance), interpreterMod.(*wasm.ModuleInstance)
+	if len(ci.Globals) == 0 {
+		return
+	}
 	for i := range ci.Globals[:len(ci.Globals)-1] { // The last global is the fuel, so we can ignore it.
 		cg := ci.Globals[i]
 		ig := ii.Globals[i]

internal/integration_test/fuzzcases/fuzzcases_test.go

@@ -585,7 +585,7 @@ func Test1797c(t *testing.T) {
 	}
 	run(t, func(t *testing.T, r wazero.Runtime) {
 		mod, err := r.Instantiate(ctx, getWasmBinary(t, "1797c"))
-		require.NoError(t, err, "wasm binary should build successfully")
+		require.NoError(t, err)
 		m := mod.(*wasm.ModuleInstance)
 		params := make([]uint64, 20)
 		_, err = m.ExportedFunction("~zz\x00E1E\x00EE\x00$").Call(ctx, params...)
@@ -600,7 +600,7 @@ func Test1797d(t *testing.T) {
 	}
 	run(t, func(t *testing.T, r wazero.Runtime) {
 		mod, err := r.Instantiate(ctx, getWasmBinary(t, "1797d"))
-		require.NoError(t, err, "wasm binary should build successfully")
+		require.NoError(t, err)
 		m := mod.(*wasm.ModuleInstance)
 		params := make([]uint64, 20)
 		_, err = m.ExportedFunction("p").Call(ctx, params...)
@@ -609,3 +609,24 @@ func Test1797d(t *testing.T) {
 		require.Equal(t, uint64(9241386435284803069), m.Globals[2].ValHi)
 	})
 }
+
+// Test1812 tests that many constant block params work fine.
+func Test1812(t *testing.T) {
+	if !platform.CompilerSupported() {
+		return
+	}
+	run(t, func(t *testing.T, r wazero.Runtime) {
+		mod, err := r.Instantiate(ctx, getWasmBinary(t, "1812"))
+		require.NoError(t, err)
+		m := mod.(*wasm.ModuleInstance)
+		res, err := m.ExportedFunction("").Call(ctx)
+		require.NoError(t, err)
+		require.Equal(t,
+			[]uint64{
+				0x8301fd00, 0xfd838783, 0x87878383, 0x9b000087, 0x170001fd,
+				0xfd8383fd, 0x87838301, 0x878787, 0x83fd9b00, 0x201fd83, 0x878783,
+				0x83fd9b00, 0x9b00fd83, 0xfd8383fd, 0x87838301, 0x87878787,
+				0xfd9b0000, 0x87878383, 0x1fd8383,
+			}, res)
+	})
+}

internal/integration_test/fuzzcases/testdata/1812.wat

@@ -0,0 +1,70 @@
+(module
+  (func (result i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32)
+    i32.const 1
+    if (result i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32)  ;; label = @1
+      i32.const 1
+      if (result i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32 i32)  ;; label = @2
+        i32.const -2097021696
+        i32.const -41711741
+        i32.const -2021162109
+        i32.const -1694498681
+        i32.const 385876477
+        i32.const -41712643
+        i32.const -2021424383
+        i32.const 8882055
+        i32.const -2080531712
+        i32.const 33684867
+        i32.const 8882051
+        i32.const -2080531712
+        i32.const -1694433917
+        i32.const -41712643
+        i32.const -2021424383
+        i32.const -2021161081
+        i32.const -40173568
+        i32.const -2021162109
+        i32.const 33391491
+      else
+        i32.const -1694498681
+        i32.const -41712643
+        i32.const -2088533247
+        i32.const -2088566275
+        i32.const -2021161085
+        i32.const 34695
+        i32.const -2088501861
+        i32.const -2097020419
+        i32.const 34695
+        i32.const -2088501861
+        i32.const -40173315
+        i32.const 33391491
+        i32.const -2021162109
+        i32.const 8882055
+        i32.const -2080531712
+        i32.const -2097021565
+        i32.const -2021161085
+        i32.const 34695
+        i32.const -2088501861
+      end
+    else
+      i32.const 0
+      i32.const 0
+      i32.const 0
+      i32.const 0
+      i32.const 0
+      i32.const 0
+      i32.const 0
+      i32.const 0
+      i32.const 0
+      i32.const 0
+      i32.const 0
+      i32.const 0
+      i32.const 0
+      i32.const 0
+      i32.const 0
+      i32.const 0
+      i32.const 0
+      i32.const 0
+      i32.const 0
+    end
+  )
+  (export "" (func 0))
+)