[Qemu-devel] [RFC 4/6] target-ppc: add cmprb instruction

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

ISA 3.0 Compare Ranged Byte instruction useful for
isupper/islower/isaplha kind of operation.

Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
---
 target-ppc/translate.c | 40 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/target-ppc/translate.c b/target-ppc/translate.c
index 93c7c66..8de217f 100644
--- a/target-ppc/translate.c
+++ b/target-ppc/translate.c
@@ -817,6 +817,45 @@ static void gen_cmpli(DisasContext *ctx)
     }
 }
 
+/* cmprb - range comparison: isupper, isaplha, islower*/
+static void gen_cmprb(DisasContext *ctx)
+{
+    TCGLabel *lab1 = gen_new_label();
+    TCGLabel *lab2 = gen_new_label();
+    TCGv src1 = tcg_temp_local_new();
+    TCGv src2 = tcg_temp_local_new();
+    TCGv src2lo = tcg_temp_local_new();
+    TCGv src2hi = tcg_temp_local_new();
+
+    tcg_gen_andi_tl(src1, cpu_gpr[rA(ctx->opcode)], 0xFF);
+    tcg_gen_andi_tl(src2, cpu_gpr[rB(ctx->opcode)], 0xFFFFFFFF);
+
+    tcg_gen_andi_tl(src2lo, src2, 0xFF);
+    tcg_gen_shri_tl(src2hi, src2, 8);
+    tcg_gen_andi_tl(src2hi, src2hi, 0xFF);
+
+    tcg_gen_brcond_tl(TCG_COND_GTU, src1, src2hi, lab1);
+    tcg_gen_brcond_tl(TCG_COND_LTU, src1, src2lo, lab1);
+    tcg_gen_movi_i32(cpu_crf[crfD(ctx->opcode)], 1 << CRF_GT);
+    tcg_gen_br(lab2);
+    gen_set_label(lab1);
+
+    if (ctx->opcode & 0x00200000) {
+        tcg_gen_shri_tl(src2hi, src2, 24);
+        tcg_gen_andi_tl(src2hi, src2hi, 0xFF);
+        tcg_gen_shri_tl(src2lo, src2, 16);
+        tcg_gen_andi_tl(src2lo, src2lo, 0xFF);
+        tcg_gen_brcond_tl(TCG_COND_GTU, src1, src2hi, lab2);
+        tcg_gen_brcond_tl(TCG_COND_LTU, src1, src2lo, lab2);
+        tcg_gen_movi_i32(cpu_crf[crfD(ctx->opcode)], 1 << CRF_GT);
+    }
+    gen_set_label(lab2);
+    tcg_temp_free(src1);
+    tcg_temp_free(src2);
+    tcg_temp_free(src2lo);
+    tcg_temp_free(src2hi);
+}
+
 /* isel (PowerPC 2.03 specification) */
 static void gen_isel(DisasContext *ctx)
 {
@@ -9898,6 +9937,7 @@ GEN_HANDLER(cmpi, 0x0B, 0xFF, 0xFF, 0x00400000, PPC_INTEGER),
 GEN_HANDLER(cmpl, 0x1F, 0x00, 0x01, 0x00400000, PPC_INTEGER),
 GEN_HANDLER(cmpli, 0x0A, 0xFF, 0xFF, 0x00400000, PPC_INTEGER),
 GEN_HANDLER_E(cmpb, 0x1F, 0x1C, 0x0F, 0x00000001, PPC_NONE, PPC2_ISA205),
+GEN_HANDLER_E(cmprb, 0x1F, 0x00, 0x06, 0x00400001, PPC_NONE, PPC2_ISA300),
 GEN_HANDLER(isel, 0x1F, 0x0F, 0xFF, 0x00000001, PPC_ISEL),
 GEN_HANDLER(addi, 0x0E, 0xFF, 0xFF, 0x00000000, PPC_INTEGER),
 GEN_HANDLER(addic, 0x0C, 0xFF, 0xFF, 0x00000000, PPC_INTEGER),
-- 
2.7.4