Fix ma_fetch test to support systems where no RVC does not imply IALIGN=32

1 files changed, 31 insertions, 9 deletions

diff --git a/isa/rv64si/ma_fetch.S b/isa/rv64si/ma_fetch.S
index 7d2adec..22eadc9 100644
--- a/isa/rv64si/ma_fetch.S
+++ b/isa/rv64si/ma_fetch.S
@@ -107,13 +107,41 @@ RVTEST_CODE_BEGIN
 2:
 
 #ifdef __MACHINE_MODE
-  # RVC cannot be disabled if doing so would cause a misaligned instruction
+  # Skip if C cannot be enabled
+  csrsi misa, 1 << ('c' - 'a')
+  csrr t2, misa
+  andi t2, t2, 1 << ('c' - 'a')
+  beqz t2, pass
+
+  # Skip if C cannot be disabled
+  csrci misa, 1 << ('c' - 'a')
+  csrr t2, misa
+  andi t2, t2, 1 << ('c' - 'a')
+  bnez t2, pass
+
+  # Skip if clearing misa.C does not set IALIGN=32
+  csrr t0, mepc
+  la t1, 1f
+  addi t1, t1, 2
+  csrw mepc, t1
+  j 1f
+
+  .option rvc
+  c.nop
+1:
+  j pass
+  .option norvc
+2:
+  csrw mepc, t0
+  csrsi misa, 1 << ('c' - 'a')
+
+  # IALIGN=32 cannot be set if doing so would cause a misaligned instruction
   # exception on the next instruction fetch. (This test assumes no other
   # extensions that support misalignment are present.)
   li TESTNUM, 8
   csrr t2, misa
   andi t2, t2, 1 << ('c' - 'a')
-  beqz t2, 2f
+  beqz t2, pass
 
   .option rvc
   c.nop
@@ -126,18 +154,13 @@ RVTEST_CODE_BEGIN
   andi t2, t2, 1 << ('c' - 'a')
   beqz t2, fail
 
-  # When RVC is disabled, mret to a misaligned mepc should succeed,
+  # IALIGN=32, mret to a misaligned mepc should succeed,
   # masking off mepc[1].
   la t0, 1f
   addi t0, t0, -2
   csrw mepc, t0
 
-  # Try to disable RVC; if it can't be disabled, skip the test.
   csrci misa, 1 << ('c' - 'a')
-  csrr t2, misa
-  andi t2, t2, 1 << ('c' - 'a')
-  bnez t2, 2f
-
   li t2, MSTATUS_MPP
   csrs mstatus, t2
   mret
@@ -148,7 +171,6 @@ RVTEST_CODE_BEGIN
   beqz x0, 1f
 1:
   csrsi misa, 1 << ('c' - 'a')
-2:
 #endif
 
   j pass