RISC-V: wrong fixup code generated for vararg calls with fixed FP args

This is a follow-up to 2076a3bb3.

Integer registers were wrongly reserved for fixed FP arguments,
causing variadic FP arguments to end up in the wrong integer registers.

Added regression test in test/regression/varargs2.c

2 files changed, 17 insertions, 0 deletions

diff --git a/test/regression/Results/varargs2 b/test/regression/Results/varargs2
index 96ee9d63..050b6331 100644
--- a/test/regression/Results/varargs2
+++ b/test/regression/Results/varargs2
@@ -10,4 +10,5 @@ Twice: -1 1.23
 With va_copy: -1 1.23
 With va_copy: -1 1.23
 With extra args: x & Hello, world! & 42 & 123456789012345 & 3.141592654 & 2.718281746
+With extra FP args: 123456789012345 & 3.141592654 & 2.718281746
 va_list compatibility: x & Hello, world! & 42 & 123456789012345 & 3.141592654 & 2.718281746
diff --git a/test/regression/varargs2.c b/test/regression/varargs2.c
index b96d1940..32140d5c 100644
--- a/test/regression/varargs2.c
+++ b/test/regression/varargs2.c
@@ -104,6 +104,17 @@ void miniprintf_extra(int i1, int i2, int i3, int i4,
   va_end(va);
 }
 
+/* Add a few dummy FP arguments to test passing of variadic FP arguments
+   in integer registers (mostly relevant for RISC-V) */
+
+void miniprintf_float(double f1, double f2, const char * fmt, ...)
+{
+  va_list va;
+  va_start(va, fmt);
+  minivprintf(fmt, va);
+  va_end(va);
+}
+
 /* Test va_list compatibility with the C library */
 
 void printf_compat(const char * fmt, ...)
@@ -143,6 +154,11 @@ int main()
                    123456789012345LL,
                    3.141592654,
                    2.71828182);
+  miniprintf_float(0.0, 1.0,
+                   "With extra FP args: %l & %e & %f\n",
+                   123456789012345LL,
+                   3.141592654,
+                   2.71828182);
   printf_compat("va_list compatibility: %c & %s & %d & %lld & %.10g & %.10g\n",
                 'x',
                 "Hello, world!",