[PATCH 5/5] powerpc sstep: Add tests for Prefixed Add Immediate

[Jordan Niethe]

Use the existing support for testing compute type instructions to test
Prefixed Add Immediate (paddi).  The R bit of the paddi instruction
controls whether current instruction address is used. Add test cases for
when R=1 and for R=0. paddi has a 34 bit immediate field formed by
concatenating si0 and si1. Add tests for the extreme values of this
field.

Skip the paddi tests if ISA v3.1 is unsupported.

Some of these test cases were added by Balamuruhan S.

Signed-off-by: Jordan Niethe <jniethe5 at gmail.com>
---
 arch/powerpc/lib/test_emulate_step.c          | 127 ++++++++++++++++++
 .../lib/test_emulate_step_exec_instr.S        |   1 +
 2 files changed, 128 insertions(+)

diff --git a/arch/powerpc/lib/test_emulate_step.c b/arch/powerpc/lib/test_emulate_step.c
index 579b5db80674..33a72b7d2764 100644
--- a/arch/powerpc/lib/test_emulate_step.c
+++ b/arch/powerpc/lib/test_emulate_step.c
@@ -105,6 +105,13 @@
 					___PPC_RA(a) | ___PPC_RB(b))
 #define TEST_ADDC_DOT(t, a, b)	ppc_inst(PPC_INST_ADDC | ___PPC_RT(t) |		\
 					___PPC_RA(a) | ___PPC_RB(b) | 0x1)
+#define TEST_PADDI(t, a, i, pr)	ppc_inst_prefix(PPC_PREFIX_MLS | __PPC_PRFX_R(pr) |	\
+					IMM_H(i),			\
+					PPC_INST_ADDI |			\
+					___PPC_RT(t) | ___PPC_RA(a) |	\
+					IMM_L(i))
+
+
 
 #define MAX_SUBTESTS	16
 
@@ -699,6 +706,11 @@ struct compute_test {
 	} subtests[MAX_SUBTESTS + 1];
 };
 
+/* Extreme values for si0||si1 (the MLS:D-form 34 bit immediate field) */
+#define SI_MIN BIT(33)
+#define SI_MAX (BIT(33) - 1)
+#define SI_UMAX (BIT(34) - 1)
+
 static struct compute_test compute_tests[] = {
 	{
 		.mnemonic = "nop",
@@ -1071,6 +1083,121 @@ static struct compute_test compute_tests[] = {
 				}
 			}
 		}
+	},
+	{
+		.mnemonic = "paddi",
+		.cpu_feature = CPU_FTR_ARCH_31,
+		.subtests = {
+			{
+				.descr = "RA = LONG_MIN, SI = SI_MIN, R = 0",
+				.instr = TEST_PADDI(21, 22, SI_MIN, 0),
+				.regs = {
+					.gpr[21] = 0,
+					.gpr[22] = LONG_MIN,
+				}
+			},
+			{
+				.descr = "RA = LONG_MIN, SI = SI_MAX, R = 0",
+				.instr = TEST_PADDI(21, 22, SI_MAX, 0),
+				.regs = {
+					.gpr[21] = 0,
+					.gpr[22] = LONG_MIN,
+				}
+			},
+			{
+				.descr = "RA = LONG_MAX, SI = SI_MAX, R = 0",
+				.instr = TEST_PADDI(21, 22, SI_MAX, 0),
+				.regs = {
+					.gpr[21] = 0,
+					.gpr[22] = LONG_MAX,
+				}
+			},
+			{
+				.descr = "RA = ULONG_MAX, SI = SI_UMAX, R = 0",
+				.instr = TEST_PADDI(21, 22, SI_UMAX, 0),
+				.regs = {
+					.gpr[21] = 0,
+					.gpr[22] = ULONG_MAX,
+				}
+			},
+			{
+				.descr = "RA = ULONG_MAX, SI = 0x1, R = 0",
+				.instr = TEST_PADDI(21, 22, 0x1, 0),
+				.regs = {
+					.gpr[21] = 0,
+					.gpr[22] = ULONG_MAX,
+				}
+			},
+			{
+				.descr = "RA = INT_MIN, SI = SI_MIN, R = 0",
+				.instr = TEST_PADDI(21, 22, SI_MIN, 0),
+				.regs = {
+					.gpr[21] = 0,
+					.gpr[22] = INT_MIN,
+				}
+			},
+			{
+				.descr = "RA = INT_MIN, SI = SI_MAX, R = 0",
+				.instr = TEST_PADDI(21, 22, SI_MAX, 0),
+				.regs = {
+					.gpr[21] = 0,
+					.gpr[22] = INT_MIN,
+				}
+			},
+			{
+				.descr = "RA = INT_MAX, SI = SI_MAX, R = 0",
+				.instr = TEST_PADDI(21, 22, SI_MAX, 0),
+				.regs = {
+					.gpr[21] = 0,
+					.gpr[22] = INT_MAX,
+				}
+			},
+			{
+				.descr = "RA = UINT_MAX, SI = 0x1, R = 0",
+				.instr = TEST_PADDI(21, 22, 0x1, 0),
+				.regs = {
+					.gpr[21] = 0,
+					.gpr[22] = UINT_MAX,
+				}
+			},
+			{
+				.descr = "RA = UINT_MAX, SI = SI_MAX, R = 0",
+				.instr = TEST_PADDI(21, 22, SI_MAX, 0),
+				.regs = {
+					.gpr[21] = 0,
+					.gpr[22] = UINT_MAX,
+				}
+			},
+			{
+				.descr = "RA is r0, SI = SI_MIN, R = 0",
+				.instr = TEST_PADDI(21, 0, SI_MIN, 0),
+				.regs = {
+					.gpr[21] = 0x0,
+				}
+			},
+			{
+				.descr = "RA = 0, SI = SI_MIN, R = 0",
+				.instr = TEST_PADDI(21, 22, SI_MIN, 0),
+				.regs = {
+					.gpr[21] = 0x0,
+					.gpr[22] = 0x0,
+				}
+			},
+			{
+				.descr = "RA is r0, SI = 0, R = 1",
+				.instr = TEST_PADDI(21, 0, 0, 1),
+				.regs = {
+					.gpr[21] = 0,
+				}
+			},
+			{
+				.descr = "RA is r0, SI = SI_MIN, R = 1",
+				.instr = TEST_PADDI(21, 0, SI_MIN, 1),
+				.regs = {
+					.gpr[21] = 0,
+				}
+			}
+		}
 	}
 };
 
diff --git a/arch/powerpc/lib/test_emulate_step_exec_instr.S b/arch/powerpc/lib/test_emulate_step_exec_instr.S
index 1580f34f4f4f..aef53ee77a43 100644
--- a/arch/powerpc/lib/test_emulate_step_exec_instr.S
+++ b/arch/powerpc/lib/test_emulate_step_exec_instr.S
@@ -81,6 +81,7 @@ _GLOBAL(exec_instr)
 
 	/* Placeholder for the test instruction */
 1:	nop
+	nop
 	patch_site 1b patch__exec_instr
 
 	/*
-- 
2.17.1