diff --git a/amd64_translate.go b/amd64_translate.go
index 64ae5abe..c07ab7c5 100644
--- a/amd64_translate.go
+++ b/amd64_translate.go
@@ -261,9 +261,10 @@ func (c *amd64Ctx) lowerInstr(bi int, ii int, ins Instr, emitBr amd64EmitBr, emi
 			return true, fmt.Errorf("amd64 RET expects at most 1 operand: %q", ins.Raw)
 		}
 		return true, c.lowerRET()
-	case "PCALIGN", "NO_LOCAL_POINTERS", "PCDATA", "FUNCDATA", "NOP",
+	case "PCALIGN", "GO_ARGS", "NO_LOCAL_POINTERS", "PCDATA", "FUNCDATA", "NOP",
 		"PUSH_REGS_HOST_TO_ABI0()", "POP_REGS_HOST_TO_ABI0()":
-		// Alignment directive emitted by stdlib asm; no semantic effect in our IR.
+		// Go assembler metadata (including GO_ARGS's argument pointer map) has
+		// no machine-code effect here; LLVM handles the argument values directly.
 		return false, nil
 	case "ADJSP":
 		if c.goarch != "386" {
diff --git a/doc/plan9asm-corpus.md b/doc/plan9asm-corpus.md
index 80ee4bc5..9abaee17 100644
--- a/doc/plan9asm-corpus.md
+++ b/doc/plan9asm-corpus.md
@@ -210,7 +210,7 @@ silently include a nested `/v2` module that happens to share its import prefix.
 The currently tracked reports are:
 
 - `xgo-dev/llgo#2464`: `github.com/coder/websocket v1.8.15`
-- `xgo-dev/llgo#2552`: `github.com/klauspost/compress v1.20.0`
+- `xgo-dev/llgo#2552`: `github.com/klauspost/compress v1.20.1`
 - `xgo-dev/llgo#2576`: `github.com/tmthrgd/go-hex` at its latest pseudo-version
 
 The ecosystem scan also pins these latest modules:
@@ -229,7 +229,7 @@ The ecosystem scan also pins these latest modules:
 - `github.com/klauspost/reedsolomon v1.14.2`
 - `github.com/minio/highwayhash v1.0.4`
 - `github.com/modern-go/gls v0.0.0-20250215024828-78308f6bb19d`
-- `github.com/pierrec/lz4/v4 v4.1.30`
+- `github.com/pierrec/lz4/v4 v4.1.31`
 - `github.com/stevvooe/resumable v0.0.0-20180830230917-22b14a53ba50`
 - `github.com/tmthrgd/go-bitwise v0.0.0-20190904053232-1430ee983fca`
 - `github.com/tmthrgd/go-popcount v0.0.0-20190904054823-afb1ace8b04f`
diff --git a/go_translate.go b/go_translate.go
index 40e781d3..3476599b 100644
--- a/go_translate.go
+++ b/go_translate.go
@@ -779,6 +779,13 @@ func goLLVMTypeForTypeWithSizes(t types.Type, goarch string, sz types.Sizes) (LL
 		if tt.NumFields() == 0 {
 			return LLVMType("[0 x i8]"), nil
 		}
+		if parts, ok := goWordStructParts(tt, goarch, sz, sz); ok {
+			fields := make([]string, len(parts))
+			for i, part := range parts {
+				fields[i] = string(part.Type)
+			}
+			return LLVMType("{ " + strings.Join(fields, ", ") + " }"), nil
+		}
 		return "", fmt.Errorf("unsupported struct type %s", tt.String())
 	case *types.Named:
 		return goLLVMTypeForTypeWithSizes(tt.Underlying(), goarch, sz)
@@ -829,6 +836,9 @@ func goLLVMArgsAndFrameSlotsForTuple(tup *types.Tuple, goarch string, sz, frameS
 			off += int64(frameSz.Sizeof(t))
 			continue
 		}
+		if st, ok := t.Underlying().(*types.Struct); ok && st.NumFields() != 0 {
+			return nil, nil, 0, fmt.Errorf("unsupported struct frame layout %s", t.String())
+		}
 
 		ty, e := goLLVMTypeForTypeWithSizes(t, goarch, sz)
 		if e != nil {
@@ -868,10 +878,46 @@ func goFramePartsForTypeWithSizes(t types.Type, goarch string, sz, frameSz types
 		return []goFramePart{{Offset: 0, Type: Ptr, Field: 0}, {Offset: word, Type: wordTy, Field: 1}, {Offset: 2 * word, Type: wordTy, Field: 2}}, true
 	case *types.Interface:
 		return []goFramePart{{Offset: 0, Type: Ptr, Field: 0}, {Offset: word, Type: Ptr, Field: 1}}, true
+	case *types.Struct:
+		return goWordStructParts(u, goarch, sz, frameSz)
 	}
 	return nil, false
 }
 
+// goWordStructParts accepts only flat structures whose fields are exactly one
+// integer/pointer word each in both the Go value and the assembly FP frame.
+// Other structures need target-specific padding and register classification.
+// Even word-sized nested structs are rejected: supporting them would require
+// recursive flattening and nested field-index mapping instead of a single Field.
+func goWordStructParts(st *types.Struct, goarch string, sz, frameSz types.Sizes) ([]goFramePart, bool) {
+	word := int64(goWordSizeForSizes(goarch, sz))
+	if st.NumFields() == 0 || word != int64(goWordSizeForSizes(goarch, frameSz)) {
+		return nil, false
+	}
+	fields := make([]*types.Var, st.NumFields())
+	for i := range fields {
+		fields[i] = st.Field(i)
+	}
+	valueOffsets := sz.Offsetsof(fields)
+	frameOffsets := frameSz.Offsetsof(fields)
+	if sz.Sizeof(st) != int64(len(fields))*word || frameSz.Sizeof(st) != int64(len(fields))*word {
+		return nil, false
+	}
+	parts := make([]goFramePart, len(fields))
+	for i, field := range fields {
+		if valueOffsets[i] != int64(i)*word || frameOffsets[i] != int64(i)*word ||
+			sz.Sizeof(field.Type()) != word || frameSz.Sizeof(field.Type()) != word {
+			return nil, false
+		}
+		ty, err := goLLVMTypeForTypeWithSizes(field.Type(), goarch, sz)
+		if err != nil || (ty != I32 && ty != I64 && ty != Ptr) {
+			return nil, false
+		}
+		parts[i] = goFramePart{Offset: frameOffsets[i], Type: ty, Field: i}
+	}
+	return parts, true
+}
+
 func goWordSize(goarch string) int {
 	switch goarch {
 	case "amd64", "arm64", "wasm":
diff --git a/go_translate_deep_test.go b/go_translate_deep_test.go
index a788b26c..8ddda334 100644
--- a/go_translate_deep_test.go
+++ b/go_translate_deep_test.go
@@ -6,8 +6,11 @@ import (
 	"go/parser"
 	"go/token"
 	"go/types"
+	"reflect"
 	"strings"
 	"testing"
+
+	"github.com/xgo-dev/llvm"
 )
 
 func mustGoPackageWithImports(t *testing.T, pkgPath string, files map[string]string) GoPackage {
@@ -135,7 +138,8 @@ func TestGoTranslateTypeCoverage(t *testing.T) {
 		{alias, "arm64", I64, true},
 		{types.Typ[types.Complex64], "amd64", "", false},
 		{types.NewStruct(nil, nil), "amd64", LLVMType("[0 x i8]"), true},
-		{types.NewStruct([]*types.Var{types.NewVar(token.NoPos, nil, "x", types.Typ[types.Int])}, nil), "amd64", "", false},
+		{types.NewStruct([]*types.Var{types.NewVar(token.NoPos, nil, "x", types.Typ[types.Int])}, nil), "amd64", "{ i64 }", true},
+		{types.NewStruct([]*types.Var{types.NewVar(token.NoPos, nil, "x", types.Typ[types.Int8])}, nil), "amd64", "", false},
 	} {
 		got, err := goLLVMTypeForType(tc.typ, tc.goarch)
 		if (err == nil) != tc.ok || got != tc.want {
@@ -179,6 +183,93 @@ func TestGoTranslateTypeCoverage(t *testing.T) {
 	}
 }
 
+func TestGoTranslateWordStructABI(t *testing.T) {
+	pkg := mustGoPackage(t, "test/pkg", `package testpkg
+type Uint128 struct { Lo, Hi uint64 }
+func Y(t *byte, a, b Uint128, res uintptr) int32
+func X(t *byte, a, b Uint128, res uintptr) int32
+`)
+	fn := pkg.Types.Scope().Lookup("Y").(*types.Func)
+	sz := types.SizesFor("gc", "amd64")
+	sig, err := goFuncSigForDeclaredFunc("test/pkg.Y", fn, "amd64", sz, sz, true)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if want := []LLVMType{Ptr, "{ i64, i64 }", "{ i64, i64 }", I64}; !reflect.DeepEqual(sig.Args, want) {
+		t.Fatalf("args = %v, want %v", sig.Args, want)
+	}
+	if want := []FrameSlot{
+		{Offset: 0, Type: Ptr, Index: 0, Field: -1},
+		{Offset: 8, Type: I64, Index: 1, Field: 0},
+		{Offset: 16, Type: I64, Index: 1, Field: 1},
+		{Offset: 24, Type: I64, Index: 2, Field: 0},
+		{Offset: 32, Type: I64, Index: 2, Field: 1},
+		{Offset: 40, Type: I64, Index: 3, Field: -1},
+	}; !reflect.DeepEqual(sig.Frame.Params, want) {
+		t.Fatalf("frame params = %v, want %v", sig.Frame.Params, want)
+	}
+	if want := []FrameSlot{{Offset: 48, Type: I32, Index: 0, Field: -1}}; !reflect.DeepEqual(sig.Frame.Results, want) {
+		t.Fatalf("frame results = %v, want %v", sig.Frame.Results, want)
+	}
+	if _, err := goFuncSigForDeclaredFunc("test/pkg.Y", fn, "386", types.SizesFor("gc", "386"), nil, true); err == nil {
+		t.Fatal("Uint128 must not be flattened into 32-bit frame words")
+	}
+
+	tr, err := TranslateGoModule(pkg, []byte(`TEXT ·Y(SB),$56-52
+GO_ARGS
+NO_LOCAL_POINTERS
+MOVQ t+0(FP), AX
+MOVQ AX, 0(SP)
+MOVQ a_Lo+8(FP), AX
+MOVQ AX, 8(SP)
+MOVQ a_Hi+16(FP), AX
+MOVQ AX, 16(SP)
+MOVQ b_Lo+24(FP), AX
+MOVQ AX, 24(SP)
+MOVQ b_Hi+32(FP), AX
+MOVQ AX, 32(SP)
+MOVQ res+40(FP), AX
+MOVQ AX, 40(SP)
+CALL ·X(SB)
+MOVL 48(SP), AX
+MOVL AX, ret+48(FP)
+RET
+`), GoModuleOptions{GOARCH: "amd64", TargetTriple: "x86_64-unknown-linux-gnu", ResolveSym: testResolveSym("test/pkg")})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer tr.Module.Dispose()
+	if err := llvm.VerifyModule(tr.Module, llvm.ReturnStatusAction); err != nil {
+		t.Fatalf("invalid LLVM IR: %v", err)
+	}
+	ir := tr.Module.String()
+	if !strings.Contains(ir, "extractvalue { i64, i64 } %arg1, 0") || !strings.Contains(ir, "extractvalue { i64, i64 } %arg2, 1") || !strings.Contains(ir, "call i32 @\"test/pkg.X\"") {
+		t.Fatalf("missing aggregate argument forwarding in LLVM IR:\n%s", ir)
+	}
+}
+
+func TestGoTranslateWordStructGuards(t *testing.T) {
+	for _, tc := range []struct {
+		name, arg, frameArch string
+	}{
+		{"padding", "struct { a uint8; b uint64 }", "amd64"},
+		{"subword", "struct { a, b uint32 }", "amd64"},
+		{"nested", "struct { inner struct { x uint64 } }", "amd64"},
+		{"float", "struct { x float64 }", "amd64"},
+		{"frame-word-mismatch", "struct { x uintptr }", "386"},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			pkg := mustGoPackage(t, "test/pkg", "package testpkg\nfunc F(x "+tc.arg+")")
+			fn := pkg.Types.Scope().Lookup("F").(*types.Func)
+			sz := types.SizesFor("gc", "amd64")
+			frameSz := types.SizesFor("gc", tc.frameArch)
+			if _, err := goFuncSigForDeclaredFunc("test/pkg.F", fn, "amd64", sz, frameSz, true); err == nil || !strings.Contains(err.Error(), "unsupported struct") {
+				t.Fatalf("expected unsupported struct layout, got %v", err)
+			}
+		})
+	}
+}
+
 func TestGoTranslateSignatureCoverage(t *testing.T) {
 	pkg := mustGoPackage(t, "test/pkg", `package testpkg
 type S struct{}
diff --git a/testdata/corpus/go.mod b/testdata/corpus/go.mod
index 3fa2be21..464a57b9 100644
--- a/testdata/corpus/go.mod
+++ b/testdata/corpus/go.mod
@@ -13,13 +13,13 @@ require (
 	github.com/dgryski/go-bits v0.0.0-20180113010104-bd8a69a71dc2
 	github.com/dgryski/go-marvin32 v0.0.0-20240117220238-0d39e8c5a8a9
 	github.com/golang/snappy v1.0.0
-	github.com/klauspost/compress v1.20.0
+	github.com/klauspost/compress v1.20.1
 	github.com/klauspost/cpuid v1.3.1
 	github.com/klauspost/cpuid/v2 v2.4.0
 	github.com/klauspost/reedsolomon v1.14.2
 	github.com/minio/highwayhash v1.0.4
 	github.com/modern-go/gls v0.0.0-20250215024828-78308f6bb19d
-	github.com/pierrec/lz4/v4 v4.1.30
+	github.com/pierrec/lz4/v4 v4.1.31
 	github.com/stevvooe/resumable v0.0.0-20180830230917-22b14a53ba50
 	github.com/tmthrgd/go-bitwise v0.0.0-20190904053232-1430ee983fca
 	github.com/tmthrgd/go-hex v0.0.0-20190904060850-447a3041c3bc
diff --git a/testdata/corpus/go.sum b/testdata/corpus/go.sum
index 8e7ff470..50f4fa3f 100644
--- a/testdata/corpus/go.sum
+++ b/testdata/corpus/go.sum
@@ -25,6 +25,8 @@ github.com/golang/snappy v1.0.0 h1:Oy607GVXHs7RtbggtPBnr2RmDArIsAefDwvrdWvRhGs=
 github.com/golang/snappy v1.0.0/go.mod h1:/XxbfmMg8lxefKM7IXC3fBNl/7bRcc72aCRzEWrmP2Q=
 github.com/klauspost/compress v1.20.0 h1:a3C1ke2ohxFymNlb2HWAHjDeKCI90scRskErZkR0ezA=
 github.com/klauspost/compress v1.20.0/go.mod h1:LUdAzn7YLVvxLpc7y3V1m40wESHTgc1422pwwBSKYuI=
+github.com/klauspost/compress v1.20.1 h1:T7kKElXUMXrUJ2E9QhQhxFtcK5rPyLdsGZvdbLMPdiQ=
+github.com/klauspost/compress v1.20.1/go.mod h1:LUdAzn7YLVvxLpc7y3V1m40wESHTgc1422pwwBSKYuI=
 github.com/klauspost/cpuid v1.3.1 h1:5JNjFYYQrZeKRJ0734q51WCEEn2huer72Dc7K+R/b6s=
 github.com/klauspost/cpuid v1.3.1/go.mod h1:bYW4mA6ZgKPob1/Dlai2LviZJO7KGI3uoWLd42rAQw4=
 github.com/klauspost/cpuid/v2 v2.4.0 h1:S6Hrbc7+ywsr0r+RLapfGBHfyefhCTwEh3A0tV913Dw=
@@ -43,6 +45,8 @@ github.com/pierrec/lz4/v4 v4.1.29 h1:CDQY6qZOLI4DW0Nx6R1vRrifrCeQHnNXkMb0hZWXFjg
 github.com/pierrec/lz4/v4 v4.1.29/go.mod h1:EoQMVJgeeEOMsCqCzqFm2O0cJvljX2nGZjcRIPL34O4=
 github.com/pierrec/lz4/v4 v4.1.30 h1:cchX8N2DVP668WkElI9QMwVyoNabLkq1LofDHFeIrdg=
 github.com/pierrec/lz4/v4 v4.1.30/go.mod h1:EoQMVJgeeEOMsCqCzqFm2O0cJvljX2nGZjcRIPL34O4=
+github.com/pierrec/lz4/v4 v4.1.31 h1:TI8ck6XSudzSzotzAmy0+kh/KpRHaVsKLPzS97gRyNg=
+github.com/pierrec/lz4/v4 v4.1.31/go.mod h1:7SE9MC2STkNtL4PIwGhjmyVwvILaGI9/COYQNBhKM/c=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/spaolacci/murmur3 v0.0.0-20180118202830-f09979ecbc72/go.mod h1:JwIasOWyU6f++ZhiEuf87xNszmSA2myDM2Kzu9HwQUA=
diff --git a/testdata/corpus/reported-libraries.json b/testdata/corpus/reported-libraries.json
index b11dcad4..db4dc55f 100644
--- a/testdata/corpus/reported-libraries.json
+++ b/testdata/corpus/reported-libraries.json
@@ -56,7 +56,7 @@
         "https://github.com/xgo-dev/llgo/issues/2552"
       ],
       "module": "github.com/klauspost/compress",
-      "version": "v1.20.0",
+      "version": "v1.20.1",
       "inventory": {
         "darwin/amd64": {
           "asm_files": 8,
@@ -360,11 +360,14 @@
       "id": "pierrec-lz4-v4",
       "origin": "ecosystem-scan",
       "module": "github.com/pierrec/lz4/v4",
-      "version": "v4.1.30",
+      "version": "v4.1.31",
       "inventory": {
         "darwin/amd64": {
-          "asm_files": 1,
-          "packages": ["github.com/pierrec/lz4/v4/internal/lz4block"]
+          "asm_files": 2,
+          "packages": [
+            "github.com/pierrec/lz4/v4/internal/lz4block",
+            "github.com/pierrec/lz4/v4/internal/xxh32"
+          ]
         },
         "darwin/arm64": {
           "asm_files": 2,
@@ -374,8 +377,11 @@
           ]
         },
         "linux/amd64": {
-          "asm_files": 1,
-          "packages": ["github.com/pierrec/lz4/v4/internal/lz4block"]
+          "asm_files": 2,
+          "packages": [
+            "github.com/pierrec/lz4/v4/internal/lz4block",
+            "github.com/pierrec/lz4/v4/internal/xxh32"
+          ]
         },
         "linux/arm": {
           "asm_files": 2,
@@ -392,8 +398,11 @@
           ]
         },
         "windows/amd64": {
-          "asm_files": 1,
-          "packages": ["github.com/pierrec/lz4/v4/internal/lz4block"]
+          "asm_files": 2,
+          "packages": [
+            "github.com/pierrec/lz4/v4/internal/lz4block",
+            "github.com/pierrec/lz4/v4/internal/xxh32"
+          ]
         },
         "windows/arm64": {
           "asm_files": 2,