Index: lib/Target/AArch64/AArch64SVEInstrInfo.td
===================================================================
--- lib/Target/AArch64/AArch64SVEInstrInfo.td
+++ lib/Target/AArch64/AArch64SVEInstrInfo.td
@@ -1327,6 +1327,12 @@
   // SVE2 extract vector (immediate offset, constructive)
   def EXT_ZZI_B : sve2_int_perm_extract_i_cons<"ext">;
 
+  // SVE floating-point convert precision
+  def FCVTX_ZPmZ_DtoS : sve_fp_2op_p_zd<0b0001010, "fcvtx", ZPR64, ZPR32, ElementSizeD>;
+
+  // SVE floating-point convert to integer
+  defm FLOGB_ZPmZ : sve2_fp_flogb<"flogb">;
+
   // Predicated shifts
   defm SQSHL_ZPmI  : sve_int_bin_pred_shift_imm_left< 0b0110, "sqshl">;
   defm UQSHL_ZPmI  : sve_int_bin_pred_shift_imm_left< 0b0111, "uqshl">;
Index: lib/Target/AArch64/SVEInstrFormats.td
===================================================================
--- lib/Target/AArch64/SVEInstrFormats.td
+++ lib/Target/AArch64/SVEInstrFormats.td
@@ -1676,6 +1676,12 @@
   def _D : sve_fp_2op_p_zd<{ 0b11, opc }, asm, ZPR64, ZPR64, ElementSizeD>;
 }
 
+multiclass sve2_fp_flogb<string asm> {
+  def _H : sve_fp_2op_p_zd<0b0011010, asm, ZPR16, ZPR16, ElementSizeH>;
+  def _S : sve_fp_2op_p_zd<0b0011100, asm, ZPR32, ZPR32, ElementSizeS>;
+  def _D : sve_fp_2op_p_zd<0b0011110, asm, ZPR64, ZPR64, ElementSizeD>;
+}
+
 //===----------------------------------------------------------------------===//
 // SVE Floating Point Unary Operations - Unpredicated Group
 //===----------------------------------------------------------------------===//
Index: test/MC/AArch64/SVE2/fcvtx-diagnostics.s
===================================================================
--- /dev/null
+++ test/MC/AArch64/SVE2/fcvtx-diagnostics.s
@@ -0,0 +1,43 @@
+// RUN: not llvm-mc -triple=aarch64 -show-encoding -mattr=+sve2  2>&1 < %s| FileCheck %s
+
+
+// --------------------------------------------------------------------------//
+// Invalid element width
+
+fcvtx    z0.b, p0/m, z0.b
+// CHECK: [[@LINE-1]]:{{[0-9]+}}: error: invalid element width
+// CHECK-NEXT: fcvtx    z0.b, p0/m, z0.b
+// CHECK-NOT: [[@LINE-1]]:{{[0-9]+}}:
+
+fcvtx    z0.h, p0/m, z0.h
+// CHECK: [[@LINE-1]]:{{[0-9]+}}: error: invalid element width
+// CHECK-NEXT: fcvtx    z0.h, p0/m, z0.h
+// CHECK-NOT: [[@LINE-1]]:{{[0-9]+}}:
+
+fcvtx    z0.s, p0/m, z0.s
+// CHECK: [[@LINE-1]]:{{[0-9]+}}: error: invalid element width
+// CHECK-NEXT: fcvtx    z0.s, p0/m, z0.s
+// CHECK-NOT: [[@LINE-1]]:{{[0-9]+}}:
+
+fcvtx    z0.d, p0/m, z0.d
+// CHECK: [[@LINE-1]]:{{[0-9]+}}: error: invalid element width
+// CHECK-NEXT: fcvtx    z0.d, p0/m, z0.d
+// CHECK-NOT: [[@LINE-1]]:{{[0-9]+}}:
+
+
+// --------------------------------------------------------------------------//
+// Invalid predicate operation
+
+fcvtx   z0.s, p0/z, z0.d
+// CHECK: [[@LINE-1]]:{{[0-9]+}}: error: invalid operand for instruction
+// CHECK-NEXT: fcvtx   z0.s, p0/z, z0.d
+// CHECK-NOT: [[@LINE-1]]:{{[0-9]+}}:
+
+
+// --------------------------------------------------------------------------//
+// error: restricted predicate has range [0, 7].
+
+fcvtx    z0.s, p8/m, z0.d
+// CHECK: [[@LINE-1]]:{{[0-9]+}}: error: restricted predicate has range [0, 7].
+// CHECK-NEXT: fcvtx    z0.s, p8/m, z0.d
+// CHECK-NOT: [[@LINE-1]]:{{[0-9]+}}:
Index: test/MC/AArch64/SVE2/fcvtx.s
===================================================================
--- /dev/null
+++ test/MC/AArch64/SVE2/fcvtx.s
@@ -0,0 +1,50 @@
+// RUN: llvm-mc -triple=aarch64 -show-encoding -mattr=+sve2 < %s \
+// RUN:        | FileCheck %s --check-prefixes=CHECK-ENCODING,CHECK-INST
+// RUN: not llvm-mc -triple=aarch64 -show-encoding < %s 2>&1 \
+// RUN:        | FileCheck %s --check-prefix=CHECK-ERROR
+// RUN: llvm-mc -triple=aarch64 -filetype=obj -mattr=+sve2 < %s \
+// RUN:        | llvm-objdump -d -mattr=+sve2 - | FileCheck %s --check-prefix=CHECK-INST
+// RUN: llvm-mc -triple=aarch64 -filetype=obj -mattr=+sve2 < %s \
+// RUN:        | llvm-objdump -d - | FileCheck %s --check-prefix=CHECK-UNKNOWN
+
+
+fcvtx    z0.s, p0/m, z0.d
+// CHECK-INST: fcvtx    z0.s, p0/m, z0.d
+// CHECK-ENCODING: [0x00,0xa0,0x0a,0x65]
+// CHECK-ERROR: instruction requires: sve2
+// CHECK-UNKNOWN: 00 a0 0a 65 <unknown>
+
+fcvtx    z30.s, p7/m, z31.d
+// CHECK-INST: fcvtx    z30.s, p7/m, z31.d
+// CHECK-ENCODING: [0xfe,0xbf,0x0a,0x65]
+// CHECK-ERROR: instruction requires: sve2
+// CHECK-UNKNOWN: fe bf 0a 65 <unknown>
+
+
+
+// --------------------------------------------------------------------------//
+// Test compatibility with MOVPRFX instruction.
+
+movprfx z5.d, p0/z, z7.d
+// CHECK-INST: movprfx	z5.d, p0/z, z7.d
+// CHECK-ENCODING: [0xe5,0x20,0xd0,0x04]
+// CHECK-ERROR: instruction requires: sve
+// CHECK-UNKNOWN: e5 20 d0 04 <unknown>
+
+fcvtx    z5.s, p0/m, z0.d
+// CHECK-INST: fcvtx	z5.s, p0/m, z0.d
+// CHECK-ENCODING: [0x05,0xa0,0x0a,0x65]
+// CHECK-ERROR: instruction requires: sve2
+// CHECK-UNKNOWN: 05 a0 0a 65 <unknown>
+
+movprfx z5, z7
+// CHECK-INST: movprfx	z5, z7
+// CHECK-ENCODING: [0xe5,0xbc,0x20,0x04]
+// CHECK-ERROR: instruction requires: sve
+// CHECK-UNKNOWN: e5 bc 20 04 <unknown>
+
+fcvtx    z5.s, p0/m, z0.d
+// CHECK-INST: fcvtx	z5.s, p0/m, z0.d
+// CHECK-ENCODING: [0x05,0xa0,0x0a,0x65]
+// CHECK-ERROR: instruction requires: sve2
+// CHECK-UNKNOWN: 05 a0 0a 65 <unknown>
Index: test/MC/AArch64/SVE2/flogb-diagnostics.s
===================================================================
--- /dev/null
+++ test/MC/AArch64/SVE2/flogb-diagnostics.s
@@ -0,0 +1,28 @@
+// RUN: not llvm-mc -triple=aarch64 -show-encoding -mattr=+sve2  2>&1 < %s| FileCheck %s
+
+
+// --------------------------------------------------------------------------//
+// Invalid element width
+
+flogb   z0.b, p0/m, z0.b
+// CHECK: [[@LINE-1]]:{{[0-9]+}}: error: invalid element width
+// CHECK-NEXT: flogb   z0.b, p0/m, z0.b
+// CHECK-NOT: [[@LINE-1]]:{{[0-9]+}}:
+
+
+// --------------------------------------------------------------------------//
+// Invalid predicate operation
+
+flogb   z0.s, p0/z, z0.s
+// CHECK: [[@LINE-1]]:{{[0-9]+}}: error: invalid operand for instruction
+// CHECK-NEXT: flogb   z0.s, p0/z, z0.s
+// CHECK-NOT: [[@LINE-1]]:{{[0-9]+}}:
+
+
+// --------------------------------------------------------------------------//
+// Predicate not in restricted predicate range
+
+flogb   z0.s, p8/m, z0.s
+// CHECK: [[@LINE-1]]:{{[0-9]+}}: error: restricted predicate has range [0, 7]
+// CHECK-NEXT: flogb   z0.s, p8/m, z0.s
+// CHECK-NOT: [[@LINE-1]]:{{[0-9]+}}:
Index: test/MC/AArch64/SVE2/flogb.s
===================================================================
--- /dev/null
+++ test/MC/AArch64/SVE2/flogb.s
@@ -0,0 +1,54 @@
+// RUN: llvm-mc -triple=aarch64 -show-encoding -mattr=+sve2 < %s \
+// RUN:        | FileCheck %s --check-prefixes=CHECK-ENCODING,CHECK-INST
+// RUN: not llvm-mc -triple=aarch64 -show-encoding < %s 2>&1 \
+// RUN:        | FileCheck %s --check-prefix=CHECK-ERROR
+// RUN: llvm-mc -triple=aarch64 -filetype=obj -mattr=+sve2 < %s \
+// RUN:        | llvm-objdump -d -mattr=+sve2 - | FileCheck %s --check-prefix=CHECK-INST
+// RUN: llvm-mc -triple=aarch64 -filetype=obj -mattr=+sve2 < %s \
+// RUN:        | llvm-objdump -d - | FileCheck %s --check-prefix=CHECK-UNKNOWN
+
+flogb    z31.h, p7/m, z31.h
+// CHECK-INST: flogb	z31.h, p7/m, z31.h
+// CHECK-ENCODING: [0xff,0xbf,0x1a,0x65]
+// CHECK-ERROR: instruction requires: sve2
+// CHECK-UNKNOWN: ff bf 1a 65 <unknown>
+
+flogb    z31.s, p7/m, z31.s
+// CHECK-INST: flogb	z31.s, p7/m, z31.s
+// CHECK-ENCODING: [0xff,0xbf,0x1c,0x65]
+// CHECK-ERROR: instruction requires: sve2
+// CHECK-UNKNOWN: ff bf 1c 65 <unknown>
+
+flogb    z31.d, p7/m, z31.d
+// CHECK-INST: flogb	z31.d, p7/m, z31.d
+// CHECK-ENCODING: [0xff,0xbf,0x1e,0x65]
+// CHECK-ERROR: instruction requires: sve2
+// CHECK-UNKNOWN: ff bf 1e 65 <unknown>
+
+
+// --------------------------------------------------------------------------//
+// Test compatibility with MOVPRFX instruction.
+
+movprfx z4.d, p7/z, z6.d
+// CHECK-INST: movprfx	z4.d, p7/z, z6.d
+// CHECK-ENCODING: [0xc4,0x3c,0xd0,0x04]
+// CHECK-ERROR: instruction requires: sve
+// CHECK-UNKNOWN: c4 3c d0 04 <unknown>
+
+flogb    z4.d, p7/m, z31.d
+// CHECK-INST: flogb	z4.d, p7/m, z31.d
+// CHECK-ENCODING: [0xe4,0xbf,0x1e,0x65]
+// CHECK-ERROR: instruction requires: sve2
+// CHECK-UNKNOWN: e4 bf 1e 65 <unknown>
+
+movprfx z4, z6
+// CHECK-INST: movprfx	z4, z6
+// CHECK-ENCODING: [0xc4,0xbc,0x20,0x04]
+// CHECK-ERROR: instruction requires: sve
+// CHECK-UNKNOWN: c4 bc 20 04 <unknown>
+
+flogb    z4.d, p7/m, z31.d
+// CHECK-INST: flogb	z4.d, p7/m, z31.d
+// CHECK-ENCODING: [0xe4,0xbf,0x1e,0x65]
+// CHECK-ERROR: instruction requires: sve2
+// CHECK-UNKNOWN: e4 bf 1e 65 <unknown>