diff --git a/gcc/config/riscv/riscv.md b/gcc/config/riscv/riscv.md
index 1fb29da8a0b..f4cc99187ed 100644
--- a/gcc/config/riscv/riscv.md
+++ b/gcc/config/riscv/riscv.md
@@ -1368,7 +1368,7 @@ (define_insn_and_split "*zero_extendsidi2_internal"
   [(set (match_operand:DI     0 "register_operand"     "=r,r")
 	(zero_extend:DI
 	    (match_operand:SI 1 "nonimmediate_operand" " r,m")))]
-  "TARGET_64BIT && !TARGET_ZBA
+  "TARGET_64BIT && !TARGET_ZBA && !TARGET_XTHEADBB
    && !(register_operand (operands[1], SImode)
         && reg_or_subregno (operands[1]) == VL_REGNUM)"
   "@
@@ -1395,7 +1395,7 @@ (define_insn_and_split "*zero_extendhi<GPR:mode>2"
   [(set (match_operand:GPR    0 "register_operand"     "=r,r")
 	(zero_extend:GPR
 	    (match_operand:HI 1 "nonimmediate_operand" " r,m")))]
-  "!TARGET_ZBB"
+  "!TARGET_ZBB && !TARGET_XTHEADBB"
   "@
    #
    lhu\t%0,%1"
@@ -1451,7 +1451,7 @@ (define_insn_and_split "*extend<SHORT:mode><SUPERQI:mode>2"
   [(set (match_operand:SUPERQI   0 "register_operand"     "=r,r")
 	(sign_extend:SUPERQI
 	    (match_operand:SHORT 1 "nonimmediate_operand" " r,m")))]
-  "!TARGET_ZBB"
+  "!TARGET_ZBB && !TARGET_XTHEADBB"
   "@
    #
    l<SHORT:size>\t%0,%1"
diff --git a/gcc/config/riscv/thead.md b/gcc/config/riscv/thead.md
index 0623607d3dc..6a06d0dfcf2 100644
--- a/gcc/config/riscv/thead.md
+++ b/gcc/config/riscv/thead.md
@@ -59,6 +59,17 @@ (define_insn "*th_ext<mode>4"
   [(set_attr "type" "bitmanip")
    (set_attr "mode" "<GPR:MODE>")])
 
+(define_insn "*extend<SHORT:mode><SUPERQI:mode>2_th_ext"
+  [(set (match_operand:SUPERQI 0 "register_operand" "=r,r")
+	(sign_extend:SUPERQI
+	    (match_operand:SHORT 1 "nonimmediate_operand" "r,m")))]
+  "TARGET_XTHEADBB"
+  "@
+   th.ext\t%0,%1,15,0
+   l<SHORT:size>\t%0,%1"
+  [(set_attr "type" "bitmanip,load")
+   (set_attr "mode" "<SUPERQI:MODE>")])
+
 (define_insn "*th_extu<mode>4"
   [(set (match_operand:GPR 0 "register_operand" "=r")
 	(zero_extract:GPR (match_operand:GPR 1 "register_operand" "r")
@@ -72,6 +83,26 @@ (define_insn "*th_extu<mode>4"
   [(set_attr "type" "bitmanip")
    (set_attr "mode" "<GPR:MODE>")])
 
+(define_insn "*zero_extendsidi2_th_extu"
+  [(set (match_operand:DI 0 "register_operand" "=r,r")
+	(zero_extend:DI (match_operand:SI 1 "nonimmediate_operand" "r,m")))]
+  "TARGET_64BIT && TARGET_XTHEADBB"
+  "@
+   th.extu\t%0,%1,31,0
+   lwu\t%0,%1"
+  [(set_attr "type" "bitmanip,load")
+   (set_attr "mode" "SI")])
+
+(define_insn "*zero_extendhi<GPR:mode>2_th_extu"
+  [(set (match_operand:GPR 0 "register_operand" "=r,r")
+	(zero_extend:GPR (match_operand:HI 1 "nonimmediate_operand" "r,m")))]
+  "TARGET_XTHEADBB"
+  "@
+   th.extu\t%0,%1,15,0
+   lhu\t%0,%1"
+  [(set_attr "type" "bitmanip,load")
+   (set_attr "mode" "HI")])
+
 (define_insn "*th_clz<mode>2"
   [(set (match_operand:X 0 "register_operand" "=r")
 	(clz:X (match_operand:X 1 "register_operand" "r")))]
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadbb-ext-1.c b/gcc/testsuite/gcc.target/riscv/xtheadbb-ext-1.c
new file mode 100644
index 00000000000..02f6ec1417d
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadbb-ext-1.c
@@ -0,0 +1,67 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gc_xtheadbb" { target { rv64 } } } */
+/* { dg-options "-march=rv32gc_xtheadbb" { target { rv32 } } } */
+/* { dg-skip-if "" { *-*-* } { "-O0" "-Os" "-Og" } } */
+
+long sext64_32(int s32)
+{
+    return s32;
+}
+
+long sext64_16(short s16)
+{
+    return s16;
+}
+
+long sext64_8(char s8)
+{
+    return s8;
+}
+
+int sext32_64(long s64)
+{
+    return s64;
+}
+
+int sext32_16(short s16)
+{
+    return s16;
+}
+
+int sext32_8(char s8)
+{
+    return s8;
+}
+
+short sext16_64(long s64)
+{
+    return s64;
+}
+
+short sext16_32(int s32)
+{
+    return s32;
+}
+
+short sext16_8(char s8)
+{
+    return s8;
+}
+
+char sext8_64(long s64)
+{
+    return s64;
+}
+
+char sext8_32(int s32)
+{
+    return s32;
+}
+
+char sext8_16(short s16)
+{
+    return s16;
+}
+
+/* { dg-final { scan-assembler-not "slli" } } */
+/* { dg-final { scan-assembler-not "srli" } } */
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadbb-extu-1.c b/gcc/testsuite/gcc.target/riscv/xtheadbb-extu-1.c
new file mode 100644
index 00000000000..01e3eda7df2
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadbb-extu-1.c
@@ -0,0 +1,67 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv32gc_xtheadbb" { target { rv32 } } } */
+/* { dg-options "-march=rv64gc_xtheadbb" { target { rv64 } } } */
+/* { dg-skip-if "" { *-*-* } { "-O0" "-Os" "-Og" } } */
+
+unsigned long zext64_32(unsigned int u32)
+{
+    return u32; //th.extu a0, a0, 31, 0
+}
+
+unsigned long zext64_16(unsigned short u16)
+{
+    return u16;
+}
+
+unsigned long zext64_8(unsigned char u8)
+{
+    return u8;
+}
+
+unsigned int zext32_64(unsigned long u64)
+{
+    return u64;
+}
+
+unsigned int zext32_16(unsigned short u16)
+{
+    return u16;
+}
+
+unsigned int zext32_8(unsigned char u8)
+{
+    return u8;
+}
+
+unsigned short zext16_64(unsigned long u64)
+{
+    return u64;
+}
+
+unsigned short zext16_32(unsigned int u32)
+{
+    return u32;
+}
+
+unsigned short zext16_8(unsigned char u8)
+{
+    return u8;
+}
+
+unsigned char zext8_64(unsigned long u64)
+{
+    return u64;
+}
+
+unsigned char zext8_32(unsigned int u32)
+{
+    return u32;
+}
+
+unsigned char zext8_16(unsigned short u16)
+{
+    return u16;
+}
+
+/* { dg-final { scan-assembler-not "slli" } } */
+/* { dg-final { scan-assembler-not "srli" } } */
