[Qemu-devel] [PATCH RFC v0 1/6] target-ppc: add dtstsfi[q] instructions

[Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>]

From: Sandipan Das <sandipandas1990@gmail.com>

DFP Test Significance Immediate [Quad]

Signed-off-by: Sandipan Das <sandipandas1990@gmail.com>
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
---
 target-ppc/dfp_helper.c | 35 +++++++++++++++++++++++++++++++++++
 target-ppc/helper.h     |  2 ++
 target-ppc/translate.c  | 22 ++++++++++++++++++++++
 3 files changed, 59 insertions(+)

diff --git a/target-ppc/dfp_helper.c b/target-ppc/dfp_helper.c
index db0ede6..9164fe7 100644
--- a/target-ppc/dfp_helper.c
+++ b/target-ppc/dfp_helper.c
@@ -647,6 +647,41 @@ uint32_t helper_##op(CPUPPCState *env, uint64_t *a, uint64_t *b)         \
 DFP_HELPER_TSTSF(dtstsf, 64)
 DFP_HELPER_TSTSF(dtstsfq, 128)
 
+#define DFP_HELPER_TSTSFI(op, size)                                     \
+uint32_t helper_##op(CPUPPCState *env, uint32_t a, uint64_t *b)         \
+{                                                                       \
+    struct PPC_DFP dfp;                                                 \
+    unsigned uim;                                                       \
+                                                                        \
+    dfp_prepare_decimal##size(&dfp, 0, b, env);                         \
+                                                                        \
+    uim = a & 0x3F;                                                     \
+                                                                        \
+    if (unlikely(decNumberIsSpecial(&dfp.b))) {                         \
+        dfp.crbf = 1;                                                   \
+    } else if (uim == 0) {                                              \
+        dfp.crbf = 4;                                                   \
+    } else if (unlikely(decNumberIsZero(&dfp.b))) {                     \
+        /* Zero has no sig digits */                                    \
+        dfp.crbf = 4;                                                   \
+    } else {                                                            \
+        unsigned nsd = dfp.b.digits;                                    \
+        if (uim < nsd) {                                                \
+            dfp.crbf = 8;                                               \
+        } else if (uim > nsd) {                                         \
+            dfp.crbf = 4;                                               \
+        } else {                                                        \
+            dfp.crbf = 2;                                               \
+        }                                                               \
+    }                                                                   \
+                                                                        \
+    dfp_set_FPCC_from_CRBF(&dfp);                                       \
+    return dfp.crbf;                                                    \
+}
+
+DFP_HELPER_TSTSFI(dtstsfi, 64)
+DFP_HELPER_TSTSFI(dtstsfiq, 128)
+
 static void QUA_PPs(struct PPC_DFP *dfp)
 {
     dfp_set_FPRF_from_FRT(dfp);
diff --git a/target-ppc/helper.h b/target-ppc/helper.h
index 9e4bb7b..68fd19e 100644
--- a/target-ppc/helper.h
+++ b/target-ppc/helper.h
@@ -645,6 +645,8 @@ DEF_HELPER_3(dtstex, i32, env, fprp, fprp)
 DEF_HELPER_3(dtstexq, i32, env, fprp, fprp)
 DEF_HELPER_3(dtstsf, i32, env, fprp, fprp)
 DEF_HELPER_3(dtstsfq, i32, env, fprp, fprp)
+DEF_HELPER_3(dtstsfi, i32, env, i32, fprp)
+DEF_HELPER_3(dtstsfiq, i32, env, i32, fprp)
 DEF_HELPER_5(dquai, void, env, fprp, fprp, i32, i32)
 DEF_HELPER_5(dquaiq, void, env, fprp, fprp, i32, i32)
 DEF_HELPER_5(dqua, void, env, fprp, fprp, fprp, i32)
diff --git a/target-ppc/translate.c b/target-ppc/translate.c
index d522566..23ef538 100644
--- a/target-ppc/translate.c
+++ b/target-ppc/translate.c
@@ -8678,6 +8678,24 @@ static void gen_##name(DisasContext *ctx)         \
     tcg_temp_free_ptr(rb);                        \
 }
 
+#define GEN_DFP_BF_I_B(name)                      \
+static void gen_##name(DisasContext *ctx)         \
+{                                                 \
+    TCGv_i32 uim;                                 \
+    TCGv_ptr rb;                                  \
+    if (unlikely(!ctx->fpu_enabled)) {            \
+        gen_exception(ctx, POWERPC_EXCP_FPU);     \
+        return;                                   \
+    }                                             \
+    gen_update_nip(ctx, ctx->nip - 4);            \
+    uim = tcg_const_i32(UIMM5(ctx->opcode));      \
+    rb = gen_fprp_ptr(rB(ctx->opcode));           \
+    gen_helper_##name(cpu_crf[crfD(ctx->opcode)], \
+                      cpu_env, uim, rb);          \
+    tcg_temp_free_i32(uim);                       \
+    tcg_temp_free_ptr(rb);                        \
+}
+
 #define GEN_DFP_BF_A_DCM(name)                    \
 static void gen_##name(DisasContext *ctx)         \
 {                                                 \
@@ -8805,6 +8823,8 @@ GEN_DFP_BF_A_B(dtstex)
 GEN_DFP_BF_A_B(dtstexq)
 GEN_DFP_BF_A_B(dtstsf)
 GEN_DFP_BF_A_B(dtstsfq)
+GEN_DFP_BF_I_B(dtstsfi)
+GEN_DFP_BF_I_B(dtstsfiq)
 GEN_DFP_T_B_U32_U32_Rc(dquai, SIMM5, RMC)
 GEN_DFP_T_B_U32_U32_Rc(dquaiq, SIMM5, RMC)
 GEN_DFP_T_A_B_I32_Rc(dqua, RMC)
@@ -11456,6 +11476,8 @@ GEN_DFP_BF_A_B(dtstex, 0x02, 0x05),
 GEN_DFP_BF_Ap_Bp(dtstexq, 0x02, 0x05),
 GEN_DFP_BF_A_B(dtstsf, 0x02, 0x15),
 GEN_DFP_BF_A_Bp(dtstsfq, 0x02, 0x15),
+GEN_DFP_BF_A_B(dtstsfi, 0x03, 0x15),
+GEN_DFP_BF_A_Bp(dtstsfiq, 0x03, 0x15),
 GEN_DFP_TE_T_B_RMC_Rc(dquai, 0x03, 0x02),
 GEN_DFP_TE_Tp_Bp_RMC_Rc(dquaiq, 0x03, 0x02),
 GEN_DFP_T_A_B_RMC_Rc(dqua, 0x03, 0x00),
-- 
2.7.4