diff --git a/arch/amd64_ext.go b/arch/amd64_ext.go
index 90598cb..a1004a5 100644
--- a/arch/amd64_ext.go
+++ b/arch/amd64_ext.go
@@ -400,24 +400,42 @@ func (in ExtInstr) amd64Imm8(op ExtOperand, pos int) (byte, error) {
 }
 
 // encodeAmdVec3Imm fills the three-vector form with a control immediate:
-// imm, src1, src2, dest, the order the reference listings write it in.
+// imm, src1, src2, dest, the order the reference listings write it in.  An
+// entry with Mem set takes the memory shape of the second source, xmm3/m16
+// in the manual.
 func (in ExtInstr) encodeAmdVec3Imm(ops []ExtOperand) ([]byte, error) {
 	class := amd64LengthClass(in.Bytes)
 	imm, err := in.amd64Imm8(ops[0], 1)
 	if err != nil {
 		return nil, err
 	}
-	for i, op := range ops[1:] {
-		if err := in.amd64Vector(op, class, i+2); err != nil {
+	if err := in.amd64Vector(ops[1], class, 2); err != nil {
+		return nil, err
+	}
+	if in.Mem == 3 && ops[2].Kind == ExtMem {
+		base, disp, err := in.amd64Memory(ops[2], 3)
+		if err != nil {
 			return nil, err
 		}
+		if err := in.amd64Vector(ops[3], class, 4); err != nil {
+			return nil, err
+		}
+		out := amd64EncodeMemory(in.Bytes, ops[3].Reg, ops[1].Reg, base, disp)
+		return append(out, imm), nil
+	}
+	if err := in.amd64Vector(ops[2], class, 3); err != nil {
+		return nil, err
+	}
+	if err := in.amd64Vector(ops[3], class, 4); err != nil {
+		return nil, err
 	}
 	out := amd64Encode(in.Bytes, ops[3].Reg, ops[1].Reg, ops[2].Reg)
 	return append(out, imm), nil
 }
 
 // encodeAmdMask2Imm fills the opmask-destination form with a control
-// immediate: imm, src1, src2, dest.
+// immediate: imm, src1, src2, dest.  An entry with Mem set takes the memory
+// shape of the second source.
 func (in ExtInstr) encodeAmdMask2Imm(ops []ExtOperand) ([]byte, error) {
 	class := amd64LengthClass(in.Bytes)
 	imm, err := in.amd64Imm8(ops[0], 1)
@@ -427,16 +445,25 @@ func (in ExtInstr) encodeAmdMask2Imm(ops []ExtOperand) ([]byte, error) {
 	if err := in.amd64Vector(ops[1], class, 2); err != nil {
 		return nil, err
 	}
-	if err := in.amd64Vector(ops[2], class, 3); err != nil {
-		return nil, err
-	}
 	if ops[3].Kind != ExtKReg {
 		return nil, fmt.Errorf("%s: operand 4 wants an opmask register, got %s", in.Name, ops[3].Kind)
 	}
 	if err := in.amd64PlainReg(ops[3], 7, 4); err != nil {
 		return nil, err
 	}
-	out := amd64Encode(in.Bytes, ops[3].Reg, ops[1].Reg, ops[2].Reg)
+	var out []byte
+	if in.Mem == 3 && ops[2].Kind == ExtMem {
+		base, disp, err := in.amd64Memory(ops[2], 3)
+		if err != nil {
+			return nil, err
+		}
+		out = amd64EncodeMemory(in.Bytes, ops[3].Reg, ops[1].Reg, base, disp)
+		return append(out, imm), nil
+	}
+	if err := in.amd64Vector(ops[2], class, 3); err != nil {
+		return nil, err
+	}
+	out = amd64Encode(in.Bytes, ops[3].Reg, ops[1].Reg, ops[2].Reg)
 	return append(out, imm), nil
 }
 
@@ -471,12 +498,24 @@ var ExtFP16CmpPredicates = [32]string{
 }
 
 // encodeAmdVecGprVec fills the conversion form with a general-register
-// source: src1, gpr, dest.  VCVTSI2SH XMM1, XMM2, EAX style.
+// source: src1, gpr, dest.  VCVTSI2SH X1, X2, EAX style.  An entry with Mem
+// set takes the memory shape of the integer source, which the manual spells
+// r/m32: the value converts straight out of memory.
 func (in ExtInstr) encodeAmdVecGprVec(ops []ExtOperand) ([]byte, error) {
 	class := amd64LengthClass(in.Bytes)
 	if err := in.amd64Vector(ops[0], class, 1); err != nil {
 		return nil, err
 	}
+	if in.Mem == 2 && ops[1].Kind == ExtMem {
+		base, disp, err := in.amd64Memory(ops[1], 2)
+		if err != nil {
+			return nil, err
+		}
+		if err := in.amd64Vector(ops[2], class, 3); err != nil {
+			return nil, err
+		}
+		return amd64EncodeMemory(in.Bytes, ops[2].Reg, ops[0].Reg, base, disp), nil
+	}
 	if err := in.amd64Gpr(ops[1], 2); err != nil {
 		return nil, err
 	}
@@ -622,10 +661,10 @@ var amd64Extensions = []ExtInstr{
 		Bytes: []byte{0x62, 0x05, 0x06, 0x00, 0x51, 0xC0}, Form: ExtFormAmdVec3, Mem: 2, Feature: ExtFeatureFP16,
 		Ref: "Intel SDM Vol. 2C, VSQRTSH (EVEX.NDS.LIG.F3.MAP5.W0 51 /r)"},
 	{Name: "VSCALEFSH", Summary: "Scale a scalar FP16 value by the ratio of two others",
-		Bytes: []byte{0x62, 0x06, 0x05, 0x00, 0x2D, 0xC0}, Form: ExtFormAmdVec3, Feature: ExtFeatureFP16,
+		Bytes: []byte{0x62, 0x06, 0x05, 0x00, 0x2D, 0xC0}, Form: ExtFormAmdVec3, Mem: 2, Feature: ExtFeatureFP16,
 		Ref: "Intel SDM Vol. 2C, VSCALEFSH (EVEX.NDS.LIG.66.MAP6.W0 2D /r)"},
 	{Name: "VGETEXPSH", Summary: "Convert the exponent of a scalar FP16 value to an FP16 value",
-		Bytes: []byte{0x62, 0x06, 0x05, 0x00, 0x43, 0xC0}, Form: ExtFormAmdVec3, Feature: ExtFeatureFP16,
+		Bytes: []byte{0x62, 0x06, 0x05, 0x00, 0x43, 0xC0}, Form: ExtFormAmdVec3, Mem: 2, Feature: ExtFeatureFP16,
 		Ref: "Intel SDM Vol. 2C, VGETEXPSH (EVEX.NDS.LIG.66.MAP6.W0 43 /r)"},
 	{Name: "VCOMISH", Summary: "Compare a scalar FP16 value and set EFLAGS",
 		Bytes: []byte{0x62, 0x05, 0x04, 0x00, 0x2F, 0xC0}, Form: ExtFormAmdVec2, Mem: 1, Feature: ExtFeatureFP16,
@@ -646,16 +685,16 @@ var amd64Extensions = []ExtInstr{
 		Bytes: []byte{0x62, 0x05, 0x87, 0x00, 0x5A, 0xC0}, Form: ExtFormAmdVec3, Feature: ExtFeatureFP16,
 		Ref: "Intel SDM Vol. 2C, VCVTSD2SH (EVEX.NDS.LIG.F2.MAP5.W1 5A /r)"},
 	{Name: "VCVTSI2SH", Summary: "Convert one signed 32-bit integer to one FP16 value",
-		Bytes: []byte{0x62, 0x05, 0x06, 0x00, 0x2A, 0xC0}, Form: ExtFormAmdVecGprVec, Feature: ExtFeatureFP16,
+		Bytes: []byte{0x62, 0x05, 0x06, 0x00, 0x2A, 0xC0}, Form: ExtFormAmdVecGprVec, Mem: 2, Feature: ExtFeatureFP16,
 		Ref: "Intel SDM Vol. 2C, VCVTSI2SH (EVEX.NDS.LIG.F3.MAP5.W0 2A /r)"},
 	{Name: "VCVTSI2SH", Summary: "Convert one signed 64-bit integer to one FP16 value",
-		Bytes: []byte{0x62, 0x05, 0x86, 0x00, 0x2A, 0xC0}, Form: ExtFormAmdVecGprVec, Feature: ExtFeatureFP16,
+		Bytes: []byte{0x62, 0x05, 0x86, 0x00, 0x2A, 0xC0}, Form: ExtFormAmdVecGprVec, Mem: 2, Feature: ExtFeatureFP16,
 		Ref: "Intel SDM Vol. 2C, VCVTSI2SH (EVEX.NDS.LIG.F3.MAP5.W1 2A /r)"},
 	{Name: "VCVTUSI2SH", Summary: "Convert one unsigned 32-bit integer to one FP16 value",
-		Bytes: []byte{0x62, 0x05, 0x06, 0x00, 0x7B, 0xC0}, Form: ExtFormAmdVecGprVec, Feature: ExtFeatureFP16,
+		Bytes: []byte{0x62, 0x05, 0x06, 0x00, 0x7B, 0xC0}, Form: ExtFormAmdVecGprVec, Mem: 2, Feature: ExtFeatureFP16,
 		Ref: "Intel SDM Vol. 2C, VCVTUSI2SH (EVEX.NDS.LIG.F3.MAP5.W0 7B /r)"},
 	{Name: "VCVTUSI2SH", Summary: "Convert one unsigned 64-bit integer to one FP16 value",
-		Bytes: []byte{0x62, 0x05, 0x86, 0x00, 0x7B, 0xC0}, Form: ExtFormAmdVecGprVec, Feature: ExtFeatureFP16,
+		Bytes: []byte{0x62, 0x05, 0x86, 0x00, 0x7B, 0xC0}, Form: ExtFormAmdVecGprVec, Mem: 2, Feature: ExtFeatureFP16,
 		Ref: "Intel SDM Vol. 2C, VCVTUSI2SH (EVEX.NDS.LIG.F3.MAP5.W1 7B /r)"},
 	{Name: "VCVTSH2SI", Summary: "Convert a low FP16 value to a signed 32-bit integer",
 		Bytes: []byte{0x62, 0x05, 0x06, 0x00, 0x2D, 0xC0}, Form: ExtFormAmdVecGpr, Feature: ExtFeatureFP16,
@@ -749,15 +788,15 @@ var amd64Extensions = []ExtInstr{
 	// ExtFP16CmpPredicates above; the reserved upper nibble of the mantissa
 	// control is refused rather than encoded.
 	{Name: "VCMPSH", Summary: "Compare scalar FP16 values into an opmask under an imm8 predicate",
-		Bytes: []byte{0x62, 0x03, 0x06, 0x00, 0xC2, 0xC0}, Form: ExtFormAmdMask2Imm, Imm8: ExtImm8CmpPredicate, Feature: ExtFeatureFP16,
+		Bytes: []byte{0x62, 0x03, 0x06, 0x00, 0xC2, 0xC0}, Form: ExtFormAmdMask2Imm, Mem: 3, Imm8: ExtImm8CmpPredicate, Feature: ExtFeatureFP16,
 		Ref: "Intel SDM Vol. 2C, VCMPSH (EVEX.LLIG.F3.0F3A.W0 C2 /r /ib)"},
 	{Name: "VGETMANTSH", Summary: "Extract the normalised mantissa of a scalar FP16 value under an imm8 control",
-		Bytes: []byte{0x62, 0x03, 0x04, 0x00, 0x27, 0xC0}, Form: ExtFormAmdVec3Imm, Imm8: ExtImm8GetMant, Feature: ExtFeatureFP16,
+		Bytes: []byte{0x62, 0x03, 0x04, 0x00, 0x27, 0xC0}, Form: ExtFormAmdVec3Imm, Mem: 3, Imm8: ExtImm8GetMant, Feature: ExtFeatureFP16,
 		Ref: "Intel SDM Vol. 2C, VGETMANTSH (EVEX.LLIG.NP.0F3A.W0 27 /r /ib)"},
 	{Name: "VREDUCESH", Summary: "Reduce a scalar FP16 value by imm8 fraction bits under an imm8 round control",
-		Bytes: []byte{0x62, 0x03, 0x04, 0x00, 0x57, 0xC0}, Form: ExtFormAmdVec3Imm, Imm8: ExtImm8ScaleRound, Feature: ExtFeatureFP16,
+		Bytes: []byte{0x62, 0x03, 0x04, 0x00, 0x57, 0xC0}, Form: ExtFormAmdVec3Imm, Mem: 3, Imm8: ExtImm8ScaleRound, Feature: ExtFeatureFP16,
 		Ref: "Intel SDM Vol. 2C, VREDUCESH (EVEX.LLIG.NP.0F3A.W0 57 /r /ib)"},
 	{Name: "VRNDSCALESH", Summary: "Round a scalar FP16 value to imm8 fraction bits under an imm8 round control",
-		Bytes: []byte{0x62, 0x03, 0x04, 0x00, 0x0A, 0xC0}, Form: ExtFormAmdVec3Imm, Imm8: ExtImm8ScaleRound, Feature: ExtFeatureFP16,
+		Bytes: []byte{0x62, 0x03, 0x04, 0x00, 0x0A, 0xC0}, Form: ExtFormAmdVec3Imm, Mem: 3, Imm8: ExtImm8ScaleRound, Feature: ExtFeatureFP16,
 		Ref: "Intel SDM Vol. 2C, VRNDSCALESH (EVEX.LLIG.NP.0F3A.W0 0A /r /ib)"},
 }
diff --git a/arch/amd64_ext_test.go b/arch/amd64_ext_test.go
index 0c5a27f..49b5a54 100644
--- a/arch/amd64_ext_test.go
+++ b/arch/amd64_ext_test.go
@@ -408,6 +408,43 @@ var amd64GoldenRows = []amd64GoldenRow{
 	// list, both destinations being XMM, so the resolver cannot tell them
 	// apart and the register row above pins the 128-bit template alone.
 
+	// The remaining scalar memory forms: the scale and exponent extracts,
+	// the imm8-control group, and the integer converts, whose second
+	// source the manual spells r/m32.  The W1 integer converts take the
+	// same operand list as the W0 ones, memory carrying no width to pick
+	// between them, so the memory rows pin the W0 templates and the W1
+	// entries rest on their register rows.
+	{"vscalefsh memory source", "VSCALEFSH",
+		[]ExtOperand{ExtXmm(29), ExtMemory(9, 0), ExtXmm(30)},
+		"624615002d31", "62 46 15 00 2d 31 vscalefsh (%r9),%xmm29,%xmm30"},
+	{"vgetexpsh memory source", "VGETEXPSH",
+		[]ExtOperand{ExtXmm(29), ExtMemory(9, 0), ExtXmm(30)},
+		"624615004331", "62 46 15 00 43 31 vgetexpsh (%r9),%xmm29,%xmm30"},
+	{"vgetexpsh memory source disp8", "VGETEXPSH",
+		[]ExtOperand{ExtXmm(29), ExtMemory(1, 127), ExtXmm(30)},
+		"6266150043717f", "62 66 15 00 43 71 7f vgetexpsh 0xfe(%rcx),%xmm29,%xmm30 (Disp8(7f))"},
+	{"vcmpsh memory source", "VCMPSH",
+		[]ExtOperand{ExtImmediate(0x7b), ExtXmm(29), ExtMemory(9, 0), ExtMask(5)},
+		"62d31600c2297b", "62 d3 16 00 c2 29 7b vcmpsh $0x7b,(%r9),%xmm29,%k5"},
+	{"vcmpsh memory source disp8", "VCMPSH",
+		[]ExtOperand{ExtImmediate(0x7b), ExtXmm(29), ExtMemory(1, 127), ExtMask(5)},
+		"62f31600c2697f7b", "62 f3 16 00 c2 69 7f 7b vcmpsh $0x7b,0xfe(%rcx),%xmm29,%k5 (Disp8(7f))"},
+	{"vgetmantsh memory source", "VGETMANTSH",
+		[]ExtOperand{ExtImmediate(0x0b), ExtXmm(29), ExtMemory(9, 0), ExtXmm(30)},
+		"6243140027310b", "62 43 14 00 27 31 7b vgetmantsh $0x7b,(%r9),%xmm29,%xmm30 (opcode row only)"},
+	{"vreducesh memory source", "VREDUCESH",
+		[]ExtOperand{ExtImmediate(0x7b), ExtXmm(29), ExtMemory(9, 0), ExtXmm(30)},
+		"6243140057317b", "62 43 14 00 57 31 7b vreducesh $0x7b,(%r9),%xmm29,%xmm30"},
+	{"vrndscalesh memory source", "VRNDSCALESH",
+		[]ExtOperand{ExtImmediate(0x7b), ExtXmm(29), ExtMemory(9, 0), ExtXmm(30)},
+		"624314000a317b", "62 43 14 00 0a 31 7b vrndscalesh $0x7b,(%r9),%xmm29,%xmm30"},
+	{"vcvtsi2sh memory source", "VCVTSI2SH",
+		[]ExtOperand{ExtXmm(29), ExtMemory(9, 0), ExtXmm(30)},
+		"624516002a31", "62 45 16 00 2a 31 vcvtsi2shl (%r9),%xmm29,%xmm30"},
+	{"vcvtusi2sh memory source", "VCVTUSI2SH",
+		[]ExtOperand{ExtXmm(29), ExtMemory(9, 0), ExtXmm(30)},
+		"624516007b31", "62 45 16 00 7b 31 vcvtusi2shl (%r9),%xmm29,%xmm30"},
+
 	// High registers in a 512-bit form exercise the EVEX extension bits:
 	// with both sources above 15 the B bar and X bar bits clear, while the
 	// destination zmm23 keeps R bar set in byte one (derived from the
@@ -619,11 +656,14 @@ func TestAmd64ExtRejects(t *testing.T) {
 		{"memory in the arithmetic's destination", "VADDSH",
 			[]ExtOperand{ExtXmm(28), ExtXmm(29), ExtMemory(9, 0)},
 			"wants an XMM register"},
-		{"memory where the general register belongs", "VCVTSI2SH",
-			[]ExtOperand{ExtXmm(29), ExtMemory(9, 0), ExtXmm(30)},
-			"wants a 32-bit general register"},
-		{"memory as the compare's second source", "VCMPSH",
-			[]ExtOperand{ExtImmediate(7), ExtXmm(28), ExtMemory(9, 0), ExtMask(5)},
+		{"memory as the compare's mask destination", "VCMPSH",
+			[]ExtOperand{ExtImmediate(7), ExtXmm(28), ExtXmm(29), ExtMemory(9, 0)},
+			"wants an opmask register"},
+		{"memory as the convert's first source", "VCVTSI2SH",
+			[]ExtOperand{ExtMemory(9, 0), ExtGpr32(2), ExtXmm(30)},
+			"wants an XMM register"},
+		{"memory as the mantissa control's first source", "VGETMANTSH",
+			[]ExtOperand{ExtImmediate(0x0b), ExtMemory(9, 0), ExtXmm(29), ExtXmm(30)},
 			"wants an XMM register"},
 		{"memory as the intersect source", "VP2INTERSECTD",
 			[]ExtOperand{ExtZmm(2), ExtMemory(9, 0), ExtMask(0)},