[llvm] 8e3307f - GlobalISel: Add a clarification to G_STORE documentation

[Matt Arsenault via llvm-commits]

Author: Matt Arsenault
Date: 2020-05-26T21:20:30-04:00
New Revision: 8e3307f5519fa58827c7b030274f122b1ed36617

URL: https://github.com/llvm/llvm-project/commit/8e3307f5519fa58827c7b030274f122b1ed36617
DIFF: https://github.com/llvm/llvm-project/commit/8e3307f5519fa58827c7b030274f122b1ed36617.diff

LOG: GlobalISel: Add a clarification to G_STORE documentation

Mirror the note on G_LOAD. We probably do need to add an explicit
G_TRUNCSTORE opcode for the vector case, although I do not have a use
for it.

Added: 
    

Modified: 
    llvm/docs/GlobalISel/GenericOpcode.rst

Removed: 
    


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diff  --git a/llvm/docs/GlobalISel/GenericOpcode.rst b/llvm/docs/GlobalISel/GenericOpcode.rst
index 6372192c0088..2350b9cf3764 100644
--- a/llvm/docs/GlobalISel/GenericOpcode.rst
+++ b/llvm/docs/GlobalISel/GenericOpcode.rst
@@ -567,7 +567,11 @@ Same as G_INDEXED_LOAD except that the load performed is zero-extending, as with
 G_STORE
 ^^^^^^^
 
-Generic store. Expects a MachineMemOperand in addition to explicit operands.
+Generic store. Expects a MachineMemOperand in addition to explicit
+operands. If the stored value size is greater than the memory size,
+the high bits are implicitly truncated. If this is a vector store, the
+high elements are discarded (i.e. this does not function as a per-lane
+vector, truncating store)
 
 G_INDEXED_STORE
 ^^^^^^^^^^^^^^^