[PATCH] D81302: Fix convertBFloatAPFloatToAPInt for NaN/Inf values

[Diego Caballero via Phabricator via llvm-commits]

dcaballe created this revision.
dcaballe added reviewers: stuij, rriddle, lattner.
Herald added subscribers: llvm-commits, hiraditya.
Herald added a project: LLVM.

Bfloat type has an 8-bit exponent so the exponent of NaN/Inf numbers
must be 0xff instead of 0x1f. This is probably a copy-paste mistake
from the half float type.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D81302

Files:
  llvm/lib/Support/APFloat.cpp
  llvm/test/Assembler/bfloat.ll


Index: llvm/test/Assembler/bfloat.ll
===================================================================
--- llvm/test/Assembler/bfloat.ll
+++ llvm/test/Assembler/bfloat.ll
@@ -36,3 +36,27 @@
 ; OPT: 0x4191A00000000000
   ret float %tmp
 }
+
+; ASSEM-DISASS-LABEL @snan_bfloat
+define bfloat @snan_bfloat() {
+; ASSEM-DISASS: ret bfloat 0xR7F81
+    ret bfloat 0xR7F81
+}
+
+; ASSEM-DISASS-LABEL @qnan_bfloat
+define bfloat @qnan_bfloat() {
+; ASSEM-DISASS: ret bfloat 0xR7FC0
+    ret bfloat 0xR7FC0
+}
+
+; ASSEM-DISASS-LABEL @pos_inf_bfloat
+define bfloat @pos_inf_bfloat() {
+; ASSEM-DISASS: ret bfloat 0xR7F80
+    ret bfloat 0xR7F80
+}
+
+; ASSEM-DISASS-LABEL @neg_inf_bfloat
+define bfloat @neg_inf_bfloat() {
+; ASSEM-DISASS: ret bfloat 0xRFF80
+    ret bfloat 0xRFF80
+}
Index: llvm/lib/Support/APFloat.cpp
===================================================================
--- llvm/lib/Support/APFloat.cpp
+++ llvm/lib/Support/APFloat.cpp
@@ -3278,11 +3278,11 @@
     myexponent = 0;
     mysignificand = 0;
   } else if (category == fcInfinity) {
-    myexponent = 0x1f;
+    myexponent = 0xff;
     mysignificand = 0;
   } else {
     assert(category == fcNaN && "Unknown category!");
-    myexponent = 0x1f;
+    myexponent = 0xff;
     mysignificand = (uint32_t)*significandParts();
   }
 


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