semihosting/arm-compat-semi: don't use SET_ARG to report SYS_HEAPINFO

As per the spec:

  the PARAMETER REGISTER contains the address of a pointer to a
  four-field data block.

So we need to follow arg0 and place the results of SYS_HEAPINFO there.

Fixes: 3c37cfe0b1 ("semihosting: Change internal common-semi interfaces to use CPUState *")
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Cc: Bug 1915925 <1915925@bugs.launchpad.net>
Cc: Keith Packard <keithp@keithp.com>
Bug: https://bugs.launchpad.net/bugs/1915925
Message-Id: <20210323165308.15244-8-alex.bennee@linaro.org>

diff --git a/semihosting/arm-compat-semi.c b/semihosting/arm-compat-semi.c
index 0f0e129..fe079ca 100644 (file)
--- a/semihosting/arm-compat-semi.c
+++ b/semihosting/arm-compat-semi.c
@@ -1214,7 +1214,11 @@ target_ulong do_common_semihosting(CPUState *cs)
             for (i = 0; i < ARRAY_SIZE(retvals); i++) {
                 bool fail;
 
-                fail = SET_ARG(i, retvals[i]);
+                if (is_64bit_semihosting(env)) {
+                    fail = put_user_u64(retvals[i], arg0 + i * 8);
+                } else {
+                    fail = put_user_u32(retvals[i], arg0 + i * 4);
+                }
 
                 if (fail) {
                     /* Couldn't write back to argument block */