ignore llvm ir fast-math notation; fixes #1762

3 files changed, 22 insertions, 1 deletions

diff --git a/src/intertyper.js b/src/intertyper.js
index fa53c652..f92a04db 100644
--- a/src/intertyper.js
+++ b/src/intertyper.js
@@ -842,7 +842,7 @@ function intertyper(lines, sidePass, baseLineNums) {
       item.variant = item.tokens[1].text;
       item.tokens.splice(1, 1);
     }
-    if (item.tokens[1].text == 'exact') item.tokens.splice(1, 1); // TODO: Implement trap values
+    while (item.tokens[1].text in LLVM.MATHOP_IGNORABLES) item.tokens.splice(1, 1);
     var segments = splitTokenList(item.tokens.slice(1));
     item.params = [];
     for (var i = 1; i <= 4; i++) {
diff --git a/src/modules.js b/src/modules.js
index 673e0662..5d48ede2 100644
--- a/src/modules.js
+++ b/src/modules.js
@@ -20,6 +20,7 @@ var LLVM = {
   COMPS: set('icmp', 'fcmp'),
   CONVERSIONS: set('inttoptr', 'ptrtoint', 'uitofp', 'sitofp', 'fptosi', 'fptoui', 'fpext', 'fptrunc'),
   INTRINSICS_32: set('_llvm_memcpy_p0i8_p0i8_i64', '_llvm_memmove_p0i8_p0i8_i64', '_llvm_memset_p0i8_i64'), // intrinsics that need args converted to i32 in USE_TYPED_ARRAYS == 2
+  MATHOP_IGNORABLES: set('exact', 'nnan', 'ninf', 'nsz', 'arcp', 'fast'),
 };
 LLVM.GLOBAL_MODIFIERS = set(keys(LLVM.LINKAGES).concat(['constant', 'global', 'hidden']));
 
diff --git a/tests/test_core.py b/tests/test_core.py
index 481130c5..d7b6cf53 100644
--- a/tests/test_core.py
+++ b/tests/test_core.py
@@ -1408,6 +1408,26 @@ Succeeded!
       '''
       self.do_run(src, '*1,10,10.5,1,1.2340,0.00*\n0.50, 3.30, 3.30, 3.30\nsmall: 0.0000010000\n')
 
+  def test_fast_math(self):
+    if self.emcc_args is None: return self.skip('requires emcc')
+    Building.COMPILER_TEST_OPTS += ['-ffast-math']
+
+    self.do_run(r'''
+#include <stdio.h>
+#include <stdlib.h>
+
+int main(int argc, char** argv) {
+  char* endptr;
+  --argc, ++argv;
+  double total = 0.0;
+  for (; argc; argc--, argv++) {
+    total += strtod(*argv, &endptr);
+  }
+  printf("total: %g\n", total);
+  return 0;
+}
+''', 'total: 19', ['5', '6', '8'])
+
   def test_zerodiv(self):
     self.do_run(r'''
       #include <stdio.h>