[RFC v4 09/11] target/arm: Add support for native library calls

[Yeqi Fu]

This commit introduces support for native library calls on the
arm target. When special instructions reserved for native calls
are encountered, the code now performs address translation and
generates the corresponding native call.

Signed-off-by: Yeqi Fu <fufuyqqqqqq@gmail.com>
---
 configs/targets/aarch64-linux-user.mak |  1 +
 configs/targets/arm-linux-user.mak     |  1 +
 target/arm/tcg/translate-a64.c         | 14 ++++++++++++++
 target/arm/tcg/translate.c             | 11 +++++++++++
 4 files changed, 27 insertions(+)

diff --git a/configs/targets/aarch64-linux-user.mak 
b/configs/targets/aarch64-linux-user.mak
index ba8bc5fe3f..5a8fd98cd9 100644
--- a/configs/targets/aarch64-linux-user.mak
+++ b/configs/targets/aarch64-linux-user.mak
@@ -4,3 +4,4 @@ TARGET_XML_FILES= gdb-xml/aarch64-core.xml 
gdb-xml/aarch64-fpu.xml gdb-xml/aarch
 TARGET_HAS_BFLT=y
 CONFIG_SEMIHOSTING=y
 CONFIG_ARM_COMPATIBLE_SEMIHOSTING=y
+CONFIG_NATIVE_CALL=y
diff --git a/configs/targets/arm-linux-user.mak 
b/configs/targets/arm-linux-user.mak
index 7f5d65794c..f934fb82da 100644
--- a/configs/targets/arm-linux-user.mak
+++ b/configs/targets/arm-linux-user.mak
@@ -5,3 +5,4 @@ TARGET_XML_FILES= gdb-xml/arm-core.xml gdb-xml/arm-vfp.xml 
gdb-xml/arm-vfp3.xml
 TARGET_HAS_BFLT=y
 CONFIG_SEMIHOSTING=y
 CONFIG_ARM_COMPATIBLE_SEMIHOSTING=y
+CONFIG_NATIVE_CALL=y
diff --git a/target/arm/tcg/translate-a64.c b/target/arm/tcg/translate-a64.c
index 3baab6aa60..422d943f92 100644
--- a/target/arm/tcg/translate-a64.c
+++ b/target/arm/tcg/translate-a64.c
@@ -25,6 +25,7 @@
 #include "arm_ldst.h"
 #include "semihosting/semihost.h"
 #include "cpregs.h"
+#include "native/native.h"
 
 static TCGv_i64 cpu_X[32];
 static TCGv_i64 cpu_pc;
@@ -2400,6 +2401,19 @@ static bool trans_HLT(DisasContext *s, arg_i *a)
      * it is required for halting debug disabled: it will UNDEF.
      * Secondly, "HLT 0xf000" is the A64 semihosting syscall instruction.
      */
+    if (native_bypass_enabled() && (a->imm == 0xffff)) {
+        TCGv_i64 arg1 = tcg_temp_new_i64();
+        TCGv_i64 arg2 = tcg_temp_new_i64();
+        TCGv_i64 arg3 = tcg_temp_new_i64();
+        TCGv_i64 ret = tcg_temp_new_i64();
+        const char *fun_name = lookup_symbol((s->base.pc_next) & 0xfff);
+        tcg_gen_mov_i64(arg1, cpu_reg(s, 0));
+        tcg_gen_mov_i64(arg2, cpu_reg(s, 1));
+        tcg_gen_mov_i64(arg3, cpu_reg(s, 2));
+        gen_native_call_i64(fun_name, ret, arg1, arg2, arg3);
+        tcg_gen_mov_i64(cpu_reg(s, 0), ret);
+        return true;
+    }
     if (semihosting_enabled(s->current_el == 0) && a->imm == 0xf000) {
         gen_exception_internal_insn(s, EXCP_SEMIHOST);
     } else {
diff --git a/target/arm/tcg/translate.c b/target/arm/tcg/translate.c
index 13c88ba1b9..a095ebcea6 100644
--- a/target/arm/tcg/translate.c
+++ b/target/arm/tcg/translate.c
@@ -27,6 +27,7 @@
 #include "arm_ldst.h"
 #include "semihosting/semihost.h"
 #include "cpregs.h"
+#include "native/native.h"
 #include "exec/helper-proto.h"
 
 #define HELPER_H "helper.h"
@@ -1139,6 +1140,16 @@ static inline void gen_hlt(DisasContext *s, int imm)
      * semihosting, to provide some semblance of security
      * (and for consistency with our 32-bit semihosting).
      */
+    if (native_bypass_enabled() && (imm == 0xffff)) {
+        TCGv_i32 arg1 = load_reg(s, 0);
+        TCGv_i32 arg2 = load_reg(s, 1);
+        TCGv_i32 arg3 = load_reg(s, 2);
+        TCGv_i32 ret = tcg_temp_new_i32();
+        const char *fun_name = lookup_symbol((s->base.pc_next) & 0xfff);
+        gen_native_call_i32(fun_name, ret, arg1, arg2, arg3);
+        store_reg(s, 0, ret);
+        return;
+    }
     if (semihosting_enabled(s->current_el == 0) &&
         (imm == (s->thumb ? 0x3c : 0xf000))) {
         gen_exception_internal_insn(s, EXCP_SEMIHOST);
-- 
2.34.1