opencsd: Handle WFIT, WFET instructions as branches

When WFI/WFE are traced as branch instructions in ETMv4, the new WFIT and
WFET instructions from v8.7A and later are traced in the same manner.
Option feature for arch v8.6A.

Signed-off-by: Mike Leach <mike.leach@linaro.org>

3 files changed, 13 insertions, 9 deletions

diff --git a/decoder/include/i_dec/trc_idec_arminst.h b/decoder/include/i_dec/trc_idec_arminst.h
index f5f2454..4960df7 100644
--- a/decoder/include/i_dec/trc_idec_arminst.h
+++ b/decoder/include/i_dec/trc_idec_arminst.h
@@ -121,7 +121,7 @@ arm_barrier_t inst_A64_barrier(uint32_t inst);
 
 int inst_ARM_wfiwfe(uint32_t inst);
 int inst_Thumb_wfiwfe(uint32_t inst);
-int inst_A64_wfiwfe(uint32_t inst);
+int inst_A64_wfiwfe(uint32_t inst, struct decode_info *info);
 
 /*
 Test whether an instruction is definitely undefined, e.g. because
diff --git a/decoder/source/i_dec/trc_i_decode.cpp b/decoder/source/i_dec/trc_i_decode.cpp
index 2cf7f88..635b6c5 100644
--- a/decoder/source/i_dec/trc_i_decode.cpp
+++ b/decoder/source/i_dec/trc_i_decode.cpp
@@ -136,14 +136,12 @@ ocsd_err_t TrcIDecode::DecodeA64(ocsd_instr_info *instr_info, struct decode_info
     if(inst_A64_is_indirect_branch_link(instr_info->opcode, &instr_info->is_link, info))
     {
         instr_info->type = OCSD_INSTR_BR_INDIRECT;
-//        instr_info->is_link = inst_A64_is_branch_and_link(instr_info->opcode);
     }
     else if(inst_A64_is_direct_branch_link(instr_info->opcode, &instr_info->is_link, info))
     {
         inst_A64_branch_destination(instr_info->instr_addr,instr_info->opcode,&branchAddr);
         instr_info->type = OCSD_INSTR_BR;
         instr_info->branch_addr = (ocsd_vaddr_t)branchAddr;
-//        instr_info->is_link = inst_A64_is_branch_and_link(instr_info->opcode);
     }
     else if((barrier = inst_A64_barrier(instr_info->opcode)) != ARM_BARRIER_NONE)
     {
@@ -160,12 +158,10 @@ ocsd_err_t TrcIDecode::DecodeA64(ocsd_instr_info *instr_info, struct decode_info
             break;
         }
     }
-    else if (instr_info->wfi_wfe_branch)
+    else if (instr_info->wfi_wfe_branch && 
+             inst_A64_wfiwfe(instr_info->opcode, info))
     {
-        if (inst_A64_wfiwfe(instr_info->opcode))
-        {
-            instr_info->type = OCSD_INSTR_WFI_WFE;
-        }
+        instr_info->type = OCSD_INSTR_WFI_WFE;
     }
 
     instr_info->is_conditional = inst_A64_is_conditional(instr_info->opcode);
diff --git a/decoder/source/i_dec/trc_idec_arminst.cpp b/decoder/source/i_dec/trc_idec_arminst.cpp
index 00c0722..c83f6d1 100644
--- a/decoder/source/i_dec/trc_idec_arminst.cpp
+++ b/decoder/source/i_dec/trc_idec_arminst.cpp
@@ -258,11 +258,19 @@ int inst_A64_is_direct_branch_link(uint32_t inst, uint8_t *is_link, struct decod
     return is_direct_branch;
 }
 
-int inst_A64_wfiwfe(uint32_t inst)
+int inst_A64_wfiwfe(uint32_t inst, struct decode_info *info)
 {
     /* WFI, WFE may be traced as branches in etm 4.3++ */
     if ((inst & 0xffffffdf) == 0xd503205f)
         return 1;
+
+    /* new feature introduced post v8.3 */
+    if (OCSD_IS_ARCH_MINVER(info->arch_version, ARCH_AA64))
+    {
+        /* WFIT / WFET for later archs */
+        if ((inst & 0xffffffc0) == 0xd5031000)
+            return 1;
+    }
     return 0;
 }