diff --git a/src/target/riscv/opcodes.h b/src/target/riscv/opcodes.h
index 1164bd628..e4efc5b05 100644
--- a/src/target/riscv/opcodes.h
+++ b/src/target/riscv/opcodes.h
@@ -4,15 +4,36 @@
 #define OPENOCD_TARGET_RISCV_OPCODES_H
 
 #include "encoding.h"
+#include <assert.h>
+#include <stdbool.h>
+#include <stdint.h>
 
 #define ZERO	0
 #define T0      5
 #define S0      8
 #define S1      9
 
+#define MAX_GPR_NUM 31
+#define MAX_FPR_NUM 31
+#define MAX_VREG_NUM 31
+#define MAX_CSR_NUM 4095
+
+#define MIN_INT12 (-0x800)
+#define MAX_INT12 0x7ff
+
+#define MIN_INT13 (-0x1000)
+#define MAX_INT13 0xfff
+
+#define MIN_INT21 (-0x100000)
+#define MAX_INT21 0xfffff
+
+#define MAX_UINT5 0x1f
+#define MAX_UINT11 0x7ff
+#define MAX_UINT12 0xfff
+
 static uint32_t bits(uint32_t value, unsigned int hi, unsigned int lo)
 {
-	return (value >> lo) & ((1 << (hi+1-lo)) - 1);
+	return (value >> lo) & (((uint32_t)1 << (hi + 1 - lo)) - 1);
 }
 
 static uint32_t bit(uint32_t value, unsigned int b)
@@ -68,153 +89,246 @@ static uint32_t imm_j(uint32_t imm)
 	return (bits(imm, 19, 12) << 12) | (bit(imm, 11) << 20) | (bits(imm, 10, 1) << 21) | (bit(imm, 20) << 31);
 }
 
-static uint32_t jal(unsigned int rd, uint32_t imm) __attribute__ ((unused));
-static uint32_t jal(unsigned int rd, uint32_t imm)
+static uint32_t jal(unsigned int rd, int32_t imm) __attribute__ ((unused));
+static uint32_t jal(unsigned int rd, int32_t imm)
 {
-	return imm_j(imm) | inst_rd(rd) | MATCH_JAL;
+	assert(rd <= MAX_GPR_NUM);
+	assert((imm >= MIN_INT21) && (imm <= MAX_INT21));
+	assert((imm & 1) == 0);
+
+	return imm_j((uint32_t)imm) | inst_rd(rd) | MATCH_JAL;
 }
 
-static uint32_t csrsi(unsigned int csr, uint16_t imm) __attribute__ ((unused));
-static uint32_t csrsi(unsigned int csr, uint16_t imm)
+static uint32_t csrsi(unsigned int csr, uint8_t imm) __attribute__ ((unused));
+static uint32_t csrsi(unsigned int csr, uint8_t imm)
 {
+	assert(csr <= MAX_CSR_NUM);
+	assert(imm <= MAX_UINT5);
+
 	return imm_i(csr) | inst_rs1(imm) | MATCH_CSRRSI;
 }
 
-static uint32_t sw(unsigned int src, unsigned int base, uint16_t offset) __attribute__ ((unused));
-static uint32_t sw(unsigned int src, unsigned int base, uint16_t offset)
+static uint32_t sw(unsigned int src, unsigned int base, int16_t offset) __attribute__ ((unused));
+static uint32_t sw(unsigned int src, unsigned int base, int16_t offset)
 {
-	return imm_s(offset) | inst_rs2(src) | inst_rs1(base) | MATCH_SW;
+	assert(src <= MAX_GPR_NUM);
+	assert(base <= MAX_GPR_NUM);
+	assert((offset >= MIN_INT12) && (offset <= MAX_INT12));
+
+	return imm_s((uint16_t)offset) | inst_rs2(src) | inst_rs1(base) | MATCH_SW;
 }
 
-static uint32_t sd(unsigned int src, unsigned int base, uint16_t offset) __attribute__ ((unused));
-static uint32_t sd(unsigned int src, unsigned int base, uint16_t offset)
+static uint32_t sd(unsigned int src, unsigned int base, int16_t offset) __attribute__ ((unused));
+static uint32_t sd(unsigned int src, unsigned int base, int16_t offset)
 {
-	return imm_s(offset) | inst_rs2(src) | inst_rs1(base) | MATCH_SD;
+	assert(src <= MAX_GPR_NUM);
+	assert(base <= MAX_GPR_NUM);
+	assert((offset >= MIN_INT12) && (offset <= MAX_INT12));
+
+	return imm_s((uint16_t)offset) | inst_rs2(src) | inst_rs1(base) | MATCH_SD;
 }
 
-static uint32_t sh(unsigned int src, unsigned int base, uint16_t offset) __attribute__ ((unused));
-static uint32_t sh(unsigned int src, unsigned int base, uint16_t offset)
+static uint32_t sh(unsigned int src, unsigned int base, int16_t offset) __attribute__ ((unused));
+static uint32_t sh(unsigned int src, unsigned int base, int16_t offset)
 {
-	return imm_s(offset) | inst_rs2(src) | inst_rs1(base) | MATCH_SH;
+	assert(src <= MAX_GPR_NUM);
+	assert(base <= MAX_GPR_NUM);
+	assert((offset >= MIN_INT12) && (offset <= MAX_INT12));
+
+	return imm_s((uint16_t)offset) | inst_rs2(src) | inst_rs1(base) | MATCH_SH;
 }
 
-static uint32_t sb(unsigned int src, unsigned int base, uint16_t offset) __attribute__ ((unused));
-static uint32_t sb(unsigned int src, unsigned int base, uint16_t offset)
+static uint32_t sb(unsigned int src, unsigned int base, int16_t offset) __attribute__ ((unused));
+static uint32_t sb(unsigned int src, unsigned int base, int16_t offset)
 {
-	return imm_s(offset) | inst_rs2(src) | inst_rs1(base) | MATCH_SB;
+	assert(src <= MAX_GPR_NUM);
+	assert(base <= MAX_GPR_NUM);
+	assert((offset >= MIN_INT12) && (offset <= MAX_INT12));
+
+	return imm_s((uint16_t)offset) | inst_rs2(src) | inst_rs1(base) | MATCH_SB;
 }
 
-static uint32_t ld(unsigned int rd, unsigned int base, uint16_t offset) __attribute__ ((unused));
-static uint32_t ld(unsigned int rd, unsigned int base, uint16_t offset)
+static uint32_t ld(unsigned int rd, unsigned int base, int16_t offset) __attribute__ ((unused));
+static uint32_t ld(unsigned int rd, unsigned int base, int16_t offset)
 {
-	return imm_i(offset) | inst_rs1(base) | inst_rd(rd) | MATCH_LD;
+	assert(rd <= MAX_GPR_NUM);
+	assert(base <= MAX_GPR_NUM);
+	assert((offset >= MIN_INT12) && (offset <= MAX_INT12));
+
+	return imm_i((uint16_t)offset) | inst_rs1(base) | inst_rd(rd) | MATCH_LD;
 }
 
-static uint32_t lw(unsigned int rd, unsigned int base, uint16_t offset) __attribute__ ((unused));
-static uint32_t lw(unsigned int rd, unsigned int base, uint16_t offset)
+static uint32_t lw(unsigned int rd, unsigned int base, int16_t offset) __attribute__ ((unused));
+static uint32_t lw(unsigned int rd, unsigned int base, int16_t offset)
 {
-	return imm_i(offset) | inst_rs1(base) | inst_rd(rd) | MATCH_LW;
+	assert(rd <= MAX_GPR_NUM);
+	assert(base <= MAX_GPR_NUM);
+	assert((offset >= MIN_INT12) && (offset <= MAX_INT12));
+
+	return imm_i((uint16_t)offset) | inst_rs1(base) | inst_rd(rd) | MATCH_LW;
 }
 
-static uint32_t lh(unsigned int rd, unsigned int base, uint16_t offset) __attribute__ ((unused));
-static uint32_t lh(unsigned int rd, unsigned int base, uint16_t offset)
+static uint32_t lh(unsigned int rd, unsigned int base, int16_t offset) __attribute__ ((unused));
+static uint32_t lh(unsigned int rd, unsigned int base, int16_t offset)
 {
-	return imm_i(offset) | inst_rs1(base) | inst_rd(rd) | MATCH_LH;
+	assert(rd <= MAX_GPR_NUM);
+	assert(base <= MAX_GPR_NUM);
+	assert((offset >= MIN_INT12) && (offset <= MAX_INT12));
+
+	return imm_i((uint16_t)offset) | inst_rs1(base) | inst_rd(rd) | MATCH_LH;
 }
 
-static uint32_t lb(unsigned int rd, unsigned int base, uint16_t offset) __attribute__ ((unused));
-static uint32_t lb(unsigned int rd, unsigned int base, uint16_t offset)
+static uint32_t lb(unsigned int rd, unsigned int base, int16_t offset) __attribute__ ((unused));
+static uint32_t lb(unsigned int rd, unsigned int base, int16_t offset)
 {
-	return imm_i(offset) | inst_rs1(base) | inst_rd(rd) | MATCH_LB;
+	assert(rd <= MAX_GPR_NUM);
+	assert(base <= MAX_GPR_NUM);
+	assert((offset >= MIN_INT12) && (offset <= MAX_INT12));
+
+	return imm_i((uint16_t)offset) | inst_rs1(base) | inst_rd(rd) | MATCH_LB;
 }
 
 static uint32_t csrw(unsigned int source, unsigned int csr) __attribute__ ((unused));
 static uint32_t csrw(unsigned int source, unsigned int csr)
 {
+	assert(source <= MAX_GPR_NUM);
+	assert(csr <= MAX_CSR_NUM);
+
 	return imm_i(csr) | inst_rs1(source) | MATCH_CSRRW;
 }
 
-static uint32_t addi(unsigned int dest, unsigned int src, uint16_t imm) __attribute__ ((unused));
-static uint32_t addi(unsigned int dest, unsigned int src, uint16_t imm)
+static uint32_t addi(unsigned int dest, unsigned int src, int16_t imm) __attribute__ ((unused));
+static uint32_t addi(unsigned int dest, unsigned int src, int16_t imm)
 {
-	return imm_i(imm) | inst_rs1(src) | inst_rd(dest) | MATCH_ADDI;
+	assert(dest <= MAX_GPR_NUM);
+	assert(src <= MAX_GPR_NUM);
+	assert((imm >= MIN_INT12) && (imm <= MAX_INT12));
+
+	return imm_i((uint16_t)imm) | inst_rs1(src) | inst_rd(dest) | MATCH_ADDI;
 }
 
 static uint32_t csrr(unsigned int rd, unsigned int csr) __attribute__ ((unused));
 static uint32_t csrr(unsigned int rd, unsigned int csr)
 {
+	assert(rd <= MAX_GPR_NUM);
+	assert(csr <= MAX_CSR_NUM);
+
 	return imm_i(csr) | inst_rd(rd) | MATCH_CSRRS;
 }
 
 static uint32_t csrrs(unsigned int rd, unsigned int rs, unsigned int csr) __attribute__ ((unused));
 static uint32_t csrrs(unsigned int rd, unsigned int rs, unsigned int csr)
 {
+	assert(rd <= MAX_GPR_NUM);
+	assert(rs <= MAX_GPR_NUM);
+	assert(csr <= MAX_CSR_NUM);
+
 	return imm_i(csr) | inst_rs1(rs) | inst_rd(rd) | MATCH_CSRRS;
 }
 
 static uint32_t csrrw(unsigned int rd, unsigned int rs, unsigned int csr) __attribute__ ((unused));
 static uint32_t csrrw(unsigned int rd, unsigned int rs, unsigned int csr)
 {
+	assert(rd <= MAX_GPR_NUM);
+	assert(rs <= MAX_GPR_NUM);
+	assert(csr <= MAX_CSR_NUM);
+
 	return imm_i(csr) | inst_rs1(rs) | inst_rd(rd) | MATCH_CSRRW;
 }
 
-static uint32_t csrrci(unsigned int rd, unsigned int zimm, unsigned int csr) __attribute__ ((unused));
-static uint32_t csrrci(unsigned int rd, unsigned int zimm, unsigned int csr)
+static uint32_t csrrci(unsigned int rd, uint8_t zimm, unsigned int csr) __attribute__ ((unused));
+static uint32_t csrrci(unsigned int rd, uint8_t zimm, unsigned int csr)
 {
+	assert(rd <= MAX_GPR_NUM);
+	assert(zimm <= MAX_UINT5);
+	assert(csr <= MAX_CSR_NUM);
+
 	return imm_i(csr) | inst_rs1(zimm) | inst_rd(rd) | MATCH_CSRRCI;
 }
 
-static uint32_t csrrsi(unsigned int rd, unsigned int zimm, unsigned int csr) __attribute__ ((unused));
-static uint32_t csrrsi(unsigned int rd, unsigned int zimm, unsigned int csr)
+static uint32_t csrrsi(unsigned int rd, uint8_t zimm, unsigned int csr) __attribute__ ((unused));
+static uint32_t csrrsi(unsigned int rd, uint8_t zimm, unsigned int csr)
 {
+	assert(rd <= MAX_GPR_NUM);
+	assert(zimm <= MAX_UINT5);
+	assert(csr <= MAX_CSR_NUM);
+
 	return imm_i(csr) | inst_rs1(zimm) | inst_rd(rd) | MATCH_CSRRSI;
 }
 
-static uint32_t fsw(unsigned int src, unsigned int base, uint16_t offset) __attribute__ ((unused));
-static uint32_t fsw(unsigned int src, unsigned int base, uint16_t offset)
+static uint32_t fsw(unsigned int src, unsigned int base, int16_t offset) __attribute__ ((unused));
+static uint32_t fsw(unsigned int src, unsigned int base, int16_t offset)
 {
-	return imm_s(offset) | inst_rs2(src) | inst_rs1(base) | MATCH_FSW;
+	assert(src <= MAX_FPR_NUM);
+	assert(base <= MAX_GPR_NUM);
+	assert((offset >= MIN_INT12) && (offset <= MAX_INT12));
+
+	return imm_s((uint16_t)offset) | inst_rs2(src) | inst_rs1(base) | MATCH_FSW;
 }
 
-static uint32_t fsd(unsigned int src, unsigned int base, uint16_t offset) __attribute__ ((unused));
-static uint32_t fsd(unsigned int src, unsigned int base, uint16_t offset)
+static uint32_t fsd(unsigned int src, unsigned int base, int16_t offset) __attribute__ ((unused));
+static uint32_t fsd(unsigned int src, unsigned int base, int16_t offset)
 {
-	return imm_s(offset) | inst_rs2(src) | inst_rs1(base) | MATCH_FSD;
+	assert(src <= MAX_FPR_NUM);
+	assert(base <= MAX_GPR_NUM);
+	assert((offset >= MIN_INT12) && (offset <= MAX_INT12));
+
+	return imm_s((uint16_t)offset) | inst_rs2(src) | inst_rs1(base) | MATCH_FSD;
 }
 
-static uint32_t flw(unsigned int dest, unsigned int base, uint16_t offset) __attribute__ ((unused));
-static uint32_t flw(unsigned int dest, unsigned int base, uint16_t offset)
+static uint32_t flw(unsigned int dest, unsigned int base, int16_t offset) __attribute__ ((unused));
+static uint32_t flw(unsigned int dest, unsigned int base, int16_t offset)
 {
-	return imm_i(offset) | inst_rs1(base) | inst_rd(dest) | MATCH_FLW;
+	assert(dest <= MAX_FPR_NUM);
+	assert(base <= MAX_GPR_NUM);
+	assert((offset >= MIN_INT12) && (offset <= MAX_INT12));
+
+	return imm_i((uint16_t)offset) | inst_rs1(base) | inst_rd(dest) | MATCH_FLW;
 }
 
-static uint32_t fld(unsigned int dest, unsigned int base, uint16_t offset) __attribute__ ((unused));
-static uint32_t fld(unsigned int dest, unsigned int base, uint16_t offset)
+static uint32_t fld(unsigned int dest, unsigned int base, int16_t offset) __attribute__ ((unused));
+static uint32_t fld(unsigned int dest, unsigned int base, int16_t offset)
 {
-	return imm_i(offset) | inst_rs1(base) | inst_rd(dest) | MATCH_FLD;
+	assert(dest <= MAX_FPR_NUM);
+	assert(base <= MAX_GPR_NUM);
+	assert((offset >= MIN_INT12) && (offset <= MAX_INT12));
+
+	return imm_i((uint16_t)offset) | inst_rs1(base) | inst_rd(dest) | MATCH_FLD;
 }
 
 static uint32_t fmv_x_w(unsigned int dest, unsigned int src) __attribute__ ((unused));
 static uint32_t fmv_x_w(unsigned int dest, unsigned int src)
 {
+	assert(dest <= MAX_GPR_NUM);
+	assert(src <= MAX_FPR_NUM);
+
 	return inst_rs1(src) | inst_rd(dest) | MATCH_FMV_X_W;
 }
 
 static uint32_t fmv_x_d(unsigned int dest, unsigned int src) __attribute__ ((unused));
 static uint32_t fmv_x_d(unsigned int dest, unsigned int src)
 {
+	assert(dest <= MAX_GPR_NUM);
+	assert(src <= MAX_FPR_NUM);
+
 	return inst_rs1(src) | inst_rd(dest) | MATCH_FMV_X_D;
 }
 
 static uint32_t fmv_w_x(unsigned int dest, unsigned int src) __attribute__ ((unused));
 static uint32_t fmv_w_x(unsigned int dest, unsigned int src)
 {
+	assert(dest <= MAX_FPR_NUM);
+	assert(src <= MAX_GPR_NUM);
+
 	return inst_rs1(src) | inst_rd(dest) | MATCH_FMV_W_X;
 }
 
 static uint32_t fmv_d_x(unsigned int dest, unsigned int src) __attribute__ ((unused));
 static uint32_t fmv_d_x(unsigned int dest, unsigned int src)
 {
+	assert(dest <= MAX_FPR_NUM);
+	assert(src <= MAX_GPR_NUM);
+
 	return inst_rs1(src) | inst_rd(dest) | MATCH_FMV_D_X;
 }
 
@@ -241,59 +355,29 @@ static uint32_t fence_i(void)
 static uint32_t lui(unsigned int dest, uint32_t imm) __attribute__ ((unused));
 static uint32_t lui(unsigned int dest, uint32_t imm)
 {
+	assert(dest <= MAX_GPR_NUM);
+	assert(bits(imm, 11, 0) == 0);
+
 	return imm_u(imm) | inst_rd(dest) | MATCH_LUI;
 }
 
-/*
-static uint32_t csrci(unsigned int csr, uint16_t imm) __attribute__ ((unused));
-static uint32_t csrci(unsigned int csr, uint16_t imm)
+static uint32_t xori(unsigned int dest, unsigned int src, int16_t imm) __attribute__ ((unused));
+static uint32_t xori(unsigned int dest, unsigned int src, int16_t imm)
 {
-  return (csr << 20) |
-    (bits(imm, 4, 0) << 15) |
-    MATCH_CSRRCI;
-}
+	assert(dest <= MAX_GPR_NUM);
+	assert(src <= MAX_GPR_NUM);
+	assert((imm >= MIN_INT12) && (imm <= MAX_INT12));
 
-static uint32_t li(unsigned int dest, uint16_t imm) __attribute__ ((unused));
-static uint32_t li(unsigned int dest, uint16_t imm)
-{
-	return addi(dest, 0, imm);
-}
-
-static uint32_t fsd(unsigned int src, unsigned int base, uint16_t offset) __attribute__ ((unused));
-static uint32_t fsd(unsigned int src, unsigned int base, uint16_t offset)
-{
-  return (bits(offset, 11, 5) << 25) |
-    (bits(src, 4, 0) << 20) |
-    (base << 15) |
-    (bits(offset, 4, 0) << 7) |
-    MATCH_FSD;
-}
-
-static uint32_t ori(unsigned int dest, unsigned int src, uint16_t imm) __attribute__ ((unused));
-static uint32_t ori(unsigned int dest, unsigned int src, uint16_t imm)
-{
-  return (bits(imm, 11, 0) << 20) |
-    (src << 15) |
-    (dest << 7) |
-    MATCH_ORI;
-}
-
-static uint32_t nop(void) __attribute__ ((unused));
-static uint32_t nop(void)
-{
-  return addi(0, 0, 0);
-}
-*/
-
-static uint32_t xori(unsigned int dest, unsigned int src, uint16_t imm) __attribute__ ((unused));
-static uint32_t xori(unsigned int dest, unsigned int src, uint16_t imm)
-{
-	return imm_i(imm) | inst_rs1(src) | inst_rd(dest) | MATCH_XORI;
+	return imm_i((uint16_t)imm) | inst_rs1(src) | inst_rd(dest) | MATCH_XORI;
 }
 
 static uint32_t srli(unsigned int dest, unsigned int src, uint8_t shamt) __attribute__ ((unused));
 static uint32_t srli(unsigned int dest, unsigned int src, uint8_t shamt)
 {
+	assert(dest <= MAX_GPR_NUM);
+	assert(src <= MAX_GPR_NUM);
+	assert(shamt <= MAX_UINT5);
+
 	return inst_rs2(shamt) | inst_rs1(src) | inst_rd(dest) | MATCH_SRLI;
 }
 
@@ -307,39 +391,59 @@ static uint32_t fence_rw_rw(void)
 static uint32_t auipc(unsigned int dest) __attribute__((unused));
 static uint32_t auipc(unsigned int dest)
 {
+	assert(dest <= MAX_GPR_NUM);
+
 	return MATCH_AUIPC | inst_rd(dest);
 }
 
-static uint32_t vsetvli(unsigned int dest, unsigned int src, uint16_t imm) __attribute__((unused));
-static uint32_t vsetvli(unsigned int dest, unsigned int src, uint16_t imm)
+static uint32_t vsetvli(unsigned int dest, unsigned int src, uint16_t vtypei) __attribute__((unused));
+static uint32_t vsetvli(unsigned int dest, unsigned int src, uint16_t vtypei)
 {
-	return (bits(imm, 10, 0) << 20) | inst_rs1(src) | inst_rd(dest) | MATCH_VSETVLI;
+	assert(dest <= MAX_GPR_NUM);
+	assert(src <= MAX_GPR_NUM);
+	assert(vtypei <= MAX_UINT11);
+
+	return (bits(vtypei, 10, 0) << 20) | inst_rs1(src) | inst_rd(dest) | MATCH_VSETVLI;
 }
 
 static uint32_t vsetvl(unsigned int rd, unsigned int rs1, unsigned int rs2) __attribute__((unused));
 static uint32_t vsetvl(unsigned int rd, unsigned int rs1, unsigned int rs2)
 {
+	assert(rd <= MAX_GPR_NUM);
+	assert(rs1 <= MAX_GPR_NUM);
+	assert(rs2 <= MAX_GPR_NUM);
+
 	return inst_rd(rd) | inst_rs1(rs1) | inst_rs2(rs2) | MATCH_VSETVL;
 }
 
 static uint32_t vmv_x_s(unsigned int rd, unsigned int vs2) __attribute__((unused));
 static uint32_t vmv_x_s(unsigned int rd, unsigned int vs2)
 {
+	assert(rd <= MAX_GPR_NUM);
+	assert(vs2 <= MAX_VREG_NUM);
+
 	return inst_rs2(vs2) | inst_rd(rd) | MATCH_VMV_X_S;
 }
 
-static uint32_t vmv_s_x(unsigned int vd, unsigned int vs2) __attribute__((unused));
-static uint32_t vmv_s_x(unsigned int vd, unsigned int rs1)
+static uint32_t vmv_s_x(unsigned int vd, unsigned int rs2) __attribute__((unused));
+static uint32_t vmv_s_x(unsigned int vd, unsigned int rs2)
 {
-	return inst_rs1(rs1) | inst_rd(vd) | MATCH_VMV_S_X;
+	assert(vd <= MAX_VREG_NUM);
+	assert(rs2 <= MAX_GPR_NUM);
+
+	return inst_rs1(rs2) | inst_rd(vd) | MATCH_VMV_S_X;
 }
 
 static uint32_t vslide1down_vx(unsigned int vd, unsigned int vs2,
-		unsigned int rs1, unsigned int vm) __attribute__((unused));
+		unsigned int rs1, bool vm) __attribute__((unused));
 static uint32_t vslide1down_vx(unsigned int vd, unsigned int vs2,
-		unsigned int rs1, unsigned int vm)
+		unsigned int rs1, bool vm)
 {
-	return ((vm & 1) << 25) | inst_rs2(vs2) | inst_rs1(rs1) | inst_rd(vd) | MATCH_VSLIDE1DOWN_VX;
+	assert(vd <= MAX_VREG_NUM);
+	assert(vs2 <= MAX_VREG_NUM);
+	assert(rs1 <= MAX_GPR_NUM);
+
+	return (vm ? (1u << 25) : 0u) | inst_rs2(vs2) | inst_rs1(rs1) | inst_rd(vd) | MATCH_VSLIDE1DOWN_VX;
 }
 
 #endif /* OPENOCD_TARGET_RISCV_OPCODES_H */
diff --git a/src/target/riscv/program.c b/src/target/riscv/program.c
index 47041a72c..bf6718f4e 100644
--- a/src/target/riscv/program.c
+++ b/src/target/riscv/program.c
@@ -20,8 +20,8 @@ int riscv_program_init(struct riscv_program *p, struct target *target)
 	p->target = target;
 	p->instruction_count = 0;
 
-	for (size_t i = 0; i < RISCV_MAX_PROGBUF_SIZE; ++i)
-		p->progbuf[i] = -1;
+	for (unsigned int i = 0; i < RISCV013_MAX_PROGBUF_SIZE; ++i)
+		p->progbuf[i] = (uint32_t)(-1);
 
 	p->execution_result = RISCV_PROGBUF_EXEC_RESULT_NOT_EXECUTED;
 	return ERROR_OK;
@@ -47,9 +47,9 @@ int riscv_program_exec(struct riscv_program *p, struct target *t)
 
 	if (riscv_program_ebreak(p) != ERROR_OK) {
 		LOG_TARGET_ERROR(t, "Unable to insert ebreak into program buffer");
-		for (size_t i = 0; i < riscv_progbuf_size(p->target); ++i)
-			LOG_TARGET_ERROR(t, "ram[%02x]: DASM(0x%08" PRIx32 ") [0x%08" PRIx32 "]",
-					(int)i, p->progbuf[i], p->progbuf[i]);
+		for (unsigned int i = 0; i < riscv_progbuf_size(p->target); ++i)
+			LOG_TARGET_ERROR(t, "progbuf[%02x]: DASM(0x%08" PRIx32 ") [0x%08" PRIx32 "]",
+					i, p->progbuf[i], p->progbuf[i]);
 		return ERROR_FAIL;
 	}
 
@@ -70,27 +70,27 @@ int riscv_program_exec(struct riscv_program *p, struct target *t)
 	return ERROR_OK;
 }
 
-int riscv_program_sdr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int offset)
+int riscv_program_sdr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int16_t offset)
 {
 	return riscv_program_insert(p, sd(d, b, offset));
 }
 
-int riscv_program_swr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int offset)
+int riscv_program_swr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int16_t offset)
 {
 	return riscv_program_insert(p, sw(d, b, offset));
 }
 
-int riscv_program_shr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int offset)
+int riscv_program_shr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int16_t offset)
 {
 	return riscv_program_insert(p, sh(d, b, offset));
 }
 
-int riscv_program_sbr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int offset)
+int riscv_program_sbr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int16_t offset)
 {
 	return riscv_program_insert(p, sb(d, b, offset));
 }
 
-int riscv_program_store(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int offset,
+int riscv_program_store(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int16_t offset,
 		unsigned int size)
 {
 	switch (size) {
@@ -107,27 +107,27 @@ int riscv_program_store(struct riscv_program *p, enum gdb_regno d, enum gdb_regn
 	return ERROR_FAIL;
 }
 
-int riscv_program_ldr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int offset)
+int riscv_program_ldr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int16_t offset)
 {
 	return riscv_program_insert(p, ld(d, b, offset));
 }
 
-int riscv_program_lwr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int offset)
+int riscv_program_lwr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int16_t offset)
 {
 	return riscv_program_insert(p, lw(d, b, offset));
 }
 
-int riscv_program_lhr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int offset)
+int riscv_program_lhr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int16_t offset)
 {
 	return riscv_program_insert(p, lh(d, b, offset));
 }
 
-int riscv_program_lbr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int offset)
+int riscv_program_lbr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int16_t offset)
 {
 	return riscv_program_insert(p, lb(d, b, offset));
 }
 
-int riscv_program_load(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int offset,
+int riscv_program_load(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int16_t offset,
 		unsigned int size)
 {
 	switch (size) {
@@ -144,13 +144,13 @@ int riscv_program_load(struct riscv_program *p, enum gdb_regno d, enum gdb_regno
 	return ERROR_FAIL;
 }
 
-int riscv_program_csrrsi(struct riscv_program *p, enum gdb_regno d, unsigned int z, enum gdb_regno csr)
+int riscv_program_csrrsi(struct riscv_program *p, enum gdb_regno d, uint8_t z, enum gdb_regno csr)
 {
 	assert(csr >= GDB_REGNO_CSR0 && csr <= GDB_REGNO_CSR4095);
 	return riscv_program_insert(p, csrrsi(d, z, csr - GDB_REGNO_CSR0));
 }
 
-int riscv_program_csrrci(struct riscv_program *p, enum gdb_regno d, unsigned int z, enum gdb_regno csr)
+int riscv_program_csrrci(struct riscv_program *p, enum gdb_regno d, uint8_t z, enum gdb_regno csr)
 {
 	assert(csr >= GDB_REGNO_CSR0 && csr <= GDB_REGNO_CSR4095);
 	return riscv_program_insert(p, csrrci(d, z, csr - GDB_REGNO_CSR0));
@@ -164,7 +164,7 @@ int riscv_program_csrr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno
 
 int riscv_program_csrw(struct riscv_program *p, enum gdb_regno s, enum gdb_regno csr)
 {
-	assert(csr >= GDB_REGNO_CSR0);
+	assert(csr >= GDB_REGNO_CSR0 && csr <= GDB_REGNO_CSR4095);
 	return riscv_program_insert(p, csrrw(GDB_REGNO_ZERO, s, csr - GDB_REGNO_CSR0));
 }
 
@@ -198,8 +198,8 @@ int riscv_program_insert(struct riscv_program *p, riscv_insn_t i)
 {
 	if (p->instruction_count >= riscv_progbuf_size(p->target)) {
 		LOG_TARGET_ERROR(p->target, "Unable to insert program into progbuf, "
-			"capacity would be exceeded (progbufsize=%d).",
-			(int)riscv_progbuf_size(p->target));
+			"capacity would be exceeded (progbufsize=%u).",
+			riscv_progbuf_size(p->target));
 		return ERROR_FAIL;
 	}
 
diff --git a/src/target/riscv/program.h b/src/target/riscv/program.h
index 91f0dabaa..ba44abaf1 100644
--- a/src/target/riscv/program.h
+++ b/src/target/riscv/program.h
@@ -5,9 +5,7 @@
 
 #include "riscv.h"
 
-#define RISCV_MAX_PROGBUF_SIZE 32
-#define RISCV_REGISTER_COUNT 32
-#define RISCV_DSCRATCH_COUNT 2
+#define RISCV013_MAX_PROGBUF_SIZE 16
 
 typedef enum {
 	RISCV_PROGBUF_EXEC_RESULT_NOT_EXECUTED,
@@ -23,10 +21,10 @@ typedef enum {
 struct riscv_program {
 	struct target *target;
 
-	uint32_t progbuf[RISCV_MAX_PROGBUF_SIZE];
+	uint32_t progbuf[RISCV013_MAX_PROGBUF_SIZE];
 
 	/* Number of 32-bit instructions in the program. */
-	size_t instruction_count;
+	unsigned int instruction_count;
 
 	/* execution result of the program */
 	/* TODO: remove this field. We should make it a parameter to riscv_program_exec */
@@ -52,22 +50,22 @@ int riscv_program_insert(struct riscv_program *p, riscv_insn_t i);
 /* Helpers to assemble various instructions.  Return 0 on success.  These might
  * assemble into a multi-instruction sequence that overwrites some other
  * register, but those will be properly saved and restored. */
-int riscv_program_ldr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno a, int o);
-int riscv_program_lwr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno a, int o);
-int riscv_program_lhr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno a, int o);
-int riscv_program_lbr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno a, int o);
-int riscv_program_load(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int o,
+int riscv_program_ldr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno a, int16_t o);
+int riscv_program_lwr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno a, int16_t o);
+int riscv_program_lhr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno a, int16_t o);
+int riscv_program_lbr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno a, int16_t o);
+int riscv_program_load(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int16_t o,
 		unsigned int s);
 
-int riscv_program_sdr(struct riscv_program *p, enum gdb_regno s, enum gdb_regno a, int o);
-int riscv_program_swr(struct riscv_program *p, enum gdb_regno s, enum gdb_regno a, int o);
-int riscv_program_shr(struct riscv_program *p, enum gdb_regno s, enum gdb_regno a, int o);
-int riscv_program_sbr(struct riscv_program *p, enum gdb_regno s, enum gdb_regno a, int o);
-int riscv_program_store(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int o,
+int riscv_program_sdr(struct riscv_program *p, enum gdb_regno s, enum gdb_regno a, int16_t o);
+int riscv_program_swr(struct riscv_program *p, enum gdb_regno s, enum gdb_regno a, int16_t o);
+int riscv_program_shr(struct riscv_program *p, enum gdb_regno s, enum gdb_regno a, int16_t o);
+int riscv_program_sbr(struct riscv_program *p, enum gdb_regno s, enum gdb_regno a, int16_t o);
+int riscv_program_store(struct riscv_program *p, enum gdb_regno d, enum gdb_regno b, int16_t o,
 		unsigned int s);
 
-int riscv_program_csrrsi(struct riscv_program *p, enum gdb_regno d, unsigned int z, enum gdb_regno csr);
-int riscv_program_csrrci(struct riscv_program *p, enum gdb_regno d, unsigned int z, enum gdb_regno csr);
+int riscv_program_csrrsi(struct riscv_program *p, enum gdb_regno d, uint8_t z, enum gdb_regno csr);
+int riscv_program_csrrci(struct riscv_program *p, enum gdb_regno d, uint8_t z, enum gdb_regno csr);
 int riscv_program_csrr(struct riscv_program *p, enum gdb_regno d, enum gdb_regno csr);
 int riscv_program_csrw(struct riscv_program *p, enum gdb_regno s, enum gdb_regno csr);
 
diff --git a/src/target/riscv/riscv-011.c b/src/target/riscv/riscv-011.c
index 23542e38d..ef80e4307 100644
--- a/src/target/riscv/riscv-011.c
+++ b/src/target/riscv/riscv-011.c
@@ -251,7 +251,7 @@ static unsigned int slot_offset(const struct target *target, slot_t slot)
 }
 
 static uint32_t load(const struct target *target, unsigned int rd,
-		unsigned int base, uint16_t offset)
+		unsigned int base, int16_t offset)
 {
 	switch (riscv_xlen(target)) {
 		case 32:
@@ -264,7 +264,7 @@ static uint32_t load(const struct target *target, unsigned int rd,
 }
 
 static uint32_t store(const struct target *target, unsigned int src,
-		unsigned int base, uint16_t offset)
+		unsigned int base, int16_t offset)
 {
 	switch (riscv_xlen(target)) {
 		case 32:
@@ -280,14 +280,16 @@ static uint32_t load_slot(const struct target *target, unsigned int dest,
 		slot_t slot)
 {
 	unsigned int offset = DEBUG_RAM_START + 4 * slot_offset(target, slot);
-	return load(target, dest, ZERO, offset);
+	assert(offset <= MAX_INT12);
+	return load(target, dest, ZERO, (int16_t)offset);
 }
 
 static uint32_t store_slot(const struct target *target, unsigned int src,
 		slot_t slot)
 {
 	unsigned int offset = DEBUG_RAM_START + 4 * slot_offset(target, slot);
-	return store(target, src, ZERO, offset);
+	assert(offset <= MAX_INT12);
+	return store(target, src, ZERO, (int16_t)offset);
 }
 
 static uint16_t dram_address(unsigned int index)
@@ -599,9 +601,9 @@ static void scans_add_write32(scans_t *scans, uint16_t address, uint32_t data,
 static void scans_add_write_jump(scans_t *scans, uint16_t address,
 		bool set_interrupt)
 {
-	scans_add_write32(scans, address,
-			jal(0, (uint32_t) (DEBUG_ROM_RESUME - (DEBUG_RAM_START + 4*address))),
-			set_interrupt);
+	unsigned int jump_offset = DEBUG_ROM_RESUME - (DEBUG_RAM_START + 4 * address);
+	assert(jump_offset <= MAX_INT21);
+	scans_add_write32(scans, address, jal(0, (int32_t)jump_offset), set_interrupt);
 }
 
 /** Add a 32-bit dbus write for an instruction that loads from the indicated
@@ -780,22 +782,25 @@ static void cache_set(struct target *target, slot_t slot, uint64_t data)
 
 static void cache_set_jump(struct target *target, unsigned int index)
 {
-	cache_set32(target, index,
-			jal(0, (uint32_t) (DEBUG_ROM_RESUME - (DEBUG_RAM_START + 4*index))));
+	unsigned int jump_offset = DEBUG_ROM_RESUME - (DEBUG_RAM_START + 4 * index);
+	assert(jump_offset <= MAX_INT21);
+	cache_set32(target, index, jal(0, (int32_t)jump_offset));
 }
 
 static void cache_set_load(struct target *target, unsigned int index,
 		unsigned int reg, slot_t slot)
 {
-	uint16_t offset = DEBUG_RAM_START + 4 * slot_offset(target, slot);
-	cache_set32(target, index, load(target, reg, ZERO, offset));
+	unsigned int offset = DEBUG_RAM_START + 4 * slot_offset(target, slot);
+	assert(offset <= MAX_INT12);
+	cache_set32(target, index, load(target, reg, ZERO, (int16_t)offset));
 }
 
 static void cache_set_store(struct target *target, unsigned int index,
 		unsigned int reg, slot_t slot)
 {
-	uint16_t offset = DEBUG_RAM_START + 4 * slot_offset(target, slot);
-	cache_set32(target, index, store(target, reg, ZERO, offset));
+	unsigned int offset = DEBUG_RAM_START + 4 * slot_offset(target, slot);
+	assert(offset <= MAX_INT12);
+	cache_set32(target, index, store(target, reg, ZERO, (int16_t)offset));
 }
 
 static void dump_debug_ram(struct target *target)
@@ -1004,9 +1009,9 @@ static uint64_t cache_get(struct target *target, slot_t slot)
 static void dram_write_jump(struct target *target, unsigned int index,
 		bool set_interrupt)
 {
-	dram_write32(target, index,
-			jal(0, (uint32_t) (DEBUG_ROM_RESUME - (DEBUG_RAM_START + 4*index))),
-			set_interrupt);
+	unsigned int jump_offset = DEBUG_ROM_RESUME - (DEBUG_RAM_START + 4 * index);
+	assert(jump_offset <= MAX_INT21);
+	dram_write32(target, index, jal(0, (int32_t)jump_offset), set_interrupt);
 }
 
 static int wait_for_state(struct target *target, enum target_state state)
diff --git a/src/target/riscv/riscv-013.c b/src/target/riscv/riscv-013.c
index 23c0aa62c..1c5d60eee 100644
--- a/src/target/riscv/riscv-013.c
+++ b/src/target/riscv/riscv-013.c
@@ -4962,7 +4962,7 @@ static int write_memory_progbuf_fill_progbuf(struct target *target, uint32_t siz
 	if (riscv_program_store(&program, GDB_REGNO_S1, GDB_REGNO_S0, 0, size) != ERROR_OK)
 		return ERROR_FAIL;
 
-	if (riscv_program_addi(&program, GDB_REGNO_S0, GDB_REGNO_S0, size) != ERROR_OK)
+	if (riscv_program_addi(&program, GDB_REGNO_S0, GDB_REGNO_S0, (int16_t)size) != ERROR_OK)
 		return ERROR_FAIL;
 
 	if (riscv_program_ebreak(&program) != ERROR_OK)
@@ -5338,9 +5338,12 @@ static enum riscv_halt_reason riscv013_halt_reason(struct target *target)
 
 static int riscv013_write_progbuf(struct target *target, unsigned int index, riscv_insn_t data)
 {
+	assert(index < RISCV013_MAX_PROGBUF_SIZE);
+
 	dm013_info_t *dm = get_dm(target);
 	if (!dm)
 		return ERROR_FAIL;
+
 	if (dm->progbuf_cache[index] != data) {
 		if (dm_write(target, DM_PROGBUF0 + index, data) != ERROR_OK)
 			return ERROR_FAIL;
diff --git a/src/target/riscv/riscv.c b/src/target/riscv/riscv.c
index 377e3e849..c555b4c07 100644
--- a/src/target/riscv/riscv.c
+++ b/src/target/riscv/riscv.c
@@ -6108,17 +6108,16 @@ static enum riscv_halt_reason riscv_halt_reason(struct target *target)
 	return r->halt_reason(target);
 }
 
-size_t riscv_progbuf_size(struct target *target)
+unsigned int riscv_progbuf_size(struct target *target)
 {
 	RISCV_INFO(r);
 	return r->get_progbufsize(target);
 }
 
-int riscv_write_progbuf(struct target *target, int index, riscv_insn_t insn)
+int riscv_write_progbuf(struct target *target, unsigned int index, riscv_insn_t insn)
 {
 	RISCV_INFO(r);
-	r->write_progbuf(target, index, insn);
-	return ERROR_OK;
+	return r->write_progbuf(target, index, insn);
 }
 
 riscv_insn_t riscv_read_progbuf(struct target *target, int index)
diff --git a/src/target/riscv/riscv.h b/src/target/riscv/riscv.h
index 67a159721..031abe50b 100644
--- a/src/target/riscv/riscv.h
+++ b/src/target/riscv/riscv.h
@@ -474,10 +474,10 @@ int riscv_get_hart_state(struct target *target, enum riscv_hart_state *state);
 
 /* These helper functions let the generic program interface get target-specific
  * information. */
-size_t riscv_progbuf_size(struct target *target);
+unsigned int riscv_progbuf_size(struct target *target);
 
 riscv_insn_t riscv_read_progbuf(struct target *target, int index);
-int riscv_write_progbuf(struct target *target, int index, riscv_insn_t insn);
+int riscv_write_progbuf(struct target *target, unsigned int index, riscv_insn_t insn);
 int riscv_execute_progbuf(struct target *target, uint32_t *cmderr);
 
 void riscv_fill_dm_nop(const struct target *target, uint8_t *buf);